“[T]he analysis that “should be made explicit” refers not to the teachings in the prior art of a motivation to combine, but to the court’s analysis…. Under the flexible inquiry set forth by the Supreme Court, the district court therefore erred by failing to take account of ‘the inferences and creative steps,’ or even routine steps, that an inventor would employ and by failing to find a motivation to combine related pieces from the prior art.” Ball Aerosol, 555 F.3d at 993, 89 USPQ2d at 1877.

The Federal Circuit’s directive in Ball Aerosol was addressed to a lower court, but it applies to Office personnel as well. When setting forth a rejection, Office personnel are to continue to make appropriate findings of fact as explained in MPEP § 2141 and § 2143, and must provide a reasoned explanation as to why the invention as claimed would have been obvious to a person of ordinary skill in the art at the relevant time. This requirement for explanation remains even in situations in which Office personnel may properly rely on common sense or ordinary ingenuity. In re Van Os, 844 F.3d 1359, 1361, 121 USPQ2d 1209, 1211 (Fed. Cir. 2017) (“Absent some articulated rationale, a finding that a combination of prior art would have been ‘common sense’ or ‘intuitive’ is no different than merely stating the combination ‘would have been obvious.’”).

The Federal Circuit’s directive in Ball Aerosol was addressed to a lower court, but it applies to Office personnel as well. When setting forth a rejection, Office personnel are to continue to make appropriate findings of fact as explained in MPEP § 2141 and § 2143, and must provide a reasoned explanation as to why the invention as claimed would have been obvious to a person of ordinary skill in the art at the relevant time. This requirement for explanation remains even in situations in which Office personnel may properly rely on common sense or ordinary ingenuity. In re Van Os, 844 F.3d 1359, 1361, 121 USPQ2d 1209, 1211 (Fed. Cir. 2017) (“Absent some articulated rationale, a finding that a combination of prior art would have been ‘common sense’ or ‘intuitive’ is no different than merely stating the combination ‘would have been obvious.’”).

Note that the list of rationales provided is not intended to be an all-inclusive list. Other rationales to support a conclusion of obviousness may be relied upon by Office personnel. Any rationale employed must provide a link between the factual findings and the legal conclusion of obviousness.

The subsections below include discussions of each rationale along with examples illustrating how the cited rationales may be used to support a finding of obviousness. Some examples use the facts of pre- KSR cases to show how the rationales suggested by the Court in KSR may be used to support a finding of obviousness. The cases cited (from which the facts were derived) may not necessarily stand for the proposition that the particular rationale is the basis for the court’s holding of obviousness, but they do illustrate consistency of past decisions with the lines of reasoning laid out in KSR. Other examples are post- KSR decisions that show how the Federal Circuit has applied the principles of KSR. Cases are included that illustrate findings of obviousness as well as nonobviousness. Note that, in some instances, a single case is used in different subsections to illustrate the use of more than one rationale to support a finding of obviousness. It will often be the case that, once the Graham inquiries have been satisfactorily resolved, a conclusion of obviousness may be supported by more than one line of reasoning.

The claimed invention in Anderson’s-Black Rock, Inc. v. Pavement Salvage Co., 396 U.S. 57, 163 USPQ 673 (1969) was a paving machine which combined several well-known elements onto a single chassis. Standard prior art paving machines typically combined equipment for spreading and shaping asphalt onto a single chassis. The patent claim included the well-known element of a radiant-heat burner attached to the side of the paver for the purpose of preventing cold joints during continuous strip paving. The prior art used radiant heat for softening the asphalt to make patches, but did not use radiant heat burners to achieve continuous strip paving. All of the component parts were known in the prior art. The only difference was the combination of the “old elements” into a single device by mounting them on a single chassis. The Court found that the operation of the heater was in no way dependent on the operation of the other equipment, and that a separate heater could also be used in conjunction with a standard paving machine to achieve the same results. The Court concluded that “[t]he convenience of putting the burner together with the other elements in one machine, though perhaps a matter of great convenience, did not produce a ‘new’ or ‘different function’” and that to those skilled in the art the use of the old elements in combination would have been obvious. Id. at 60, 163 USPQ at 674.

The claimed invention in Anderson’s-Black Rock, Inc. v. Pavement Salvage Co., 396 U.S. 57, 163 USPQ 673 (1969) was a paving machine which combined several well-known elements onto a single chassis. Standard prior art paving machines typically combined equipment for spreading and shaping asphalt onto a single chassis. The patent claim included the well-known element of a radiant-heat burner attached to the side of the paver for the purpose of preventing cold joints during continuous strip paving. The prior art used radiant heat for softening the asphalt to make patches, but did not use radiant heat burners to achieve continuous strip paving. All of the component parts were known in the prior art. The only difference was the combination of the “old elements” into a single device by mounting them on a single chassis. The Court found that the operation of the heater was in no way dependent on the operation of the other equipment, and that a separate heater could also be used in conjunction with a standard paving machine to achieve the same results. The Court concluded that “[t]he convenience of putting the burner together with the other elements in one machine, though perhaps a matter of great convenience, did not produce a ‘new’ or ‘different function’” and that to those skilled in the art the use of the old elements in combination would have been obvious. Id. at 60, 163 USPQ at 674.

The claimed invention in Anderson’s-Black Rock, Inc. v. Pavement Salvage Co., 396 U.S. 57, 163 USPQ 673 (1969) was a paving machine which combined several well-known elements onto a single chassis. Standard prior art paving machines typically combined equipment for spreading and shaping asphalt onto a single chassis. The patent claim included the well-known element of a radiant-heat burner attached to the side of the paver for the purpose of preventing cold joints during continuous strip paving. The prior art used radiant heat for softening the asphalt to make patches, but did not use radiant heat burners to achieve continuous strip paving. All of the component parts were known in the prior art. The only difference was the combination of the “old elements” into a single device by mounting them on a single chassis. The Court found that the operation of the heater was in no way dependent on the operation of the other equipment, and that a separate heater could also be used in conjunction with a standard paving machine to achieve the same results. The Court concluded that “[t]he convenience of putting the burner together with the other elements in one machine, though perhaps a matter of great convenience, did not produce a ‘new’ or ‘different function’” and that to those skilled in the art the use of the old elements in combination would have been obvious. Id. at 60, 163 USPQ at 674.

The claimed invention in Anderson’s-Black Rock, Inc. v. Pavement Salvage Co., 396 U.S. 57, 163 USPQ 673 (1969) was a paving machine which combined several well-known elements onto a single chassis. Standard prior art paving machines typically combined equipment for spreading and shaping asphalt onto a single chassis. The patent claim included the well-known element of a radiant-heat burner attached to the side of the paver for the purpose of preventing cold joints during continuous strip paving. The prior art used radiant heat for softening the asphalt to make patches, but did not use radiant heat burners to achieve continuous strip paving. All of the component parts were known in the prior art. The only difference was the combination of the “old elements” into a single device by mounting them on a single chassis. The Court found that the operation of the heater was in no way dependent on the operation of the other equipment, and that a separate heater could also be used in conjunction with a standard paving machine to achieve the same results. The Court concluded that “[t]he convenience of putting the burner together with the other elements in one machine, though perhaps a matter of great convenience, did not produce a ‘new’ or ‘different function’” and that to those skilled in the art the use of the old elements in combination would have been obvious. Id. at 60, 163 USPQ at 674.

The claimed invention in Anderson’s-Black Rock, Inc. v. Pavement Salvage Co., 396 U.S. 57, 163 USPQ 673 (1969) was a paving machine which combined several well-known elements onto a single chassis. Standard prior art paving machines typically combined equipment for spreading and shaping asphalt onto a single chassis. The patent claim included the well-known element of a radiant-heat burner attached to the side of the paver for the purpose of preventing cold joints during continuous strip paving. The prior art used radiant heat for softening the asphalt to make patches, but did not use radiant heat burners to achieve continuous strip paving. All of the component parts were known in the prior art. The only difference was the combination of the “old elements” into a single device by mounting them on a single chassis. The Court found that the operation of the heater was in no way dependent on the operation of the other equipment, and that a separate heater could also be used in conjunction with a standard paving machine to achieve the same results. The Court concluded that “[t]he convenience of putting the burner together with the other elements in one machine, though perhaps a matter of great convenience, did not produce a ‘new’ or ‘different function’” and that to those skilled in the art the use of the old elements in combination would have been obvious. Id. at 60, 163 USPQ at 674.

The claimed invention in Anderson’s-Black Rock, Inc. v. Pavement Salvage Co., 396 U.S. 57, 163 USPQ 673 (1969) was a paving machine which combined several well-known elements onto a single chassis. Standard prior art paving machines typically combined equipment for spreading and shaping asphalt onto a single chassis. The patent claim included the well-known element of a radiant-heat burner attached to the side of the paver for the purpose of preventing cold joints during continuous strip paving. The prior art used radiant heat for softening the asphalt to make patches, but did not use radiant heat burners to achieve continuous strip paving. All of the component parts were known in the prior art. The only difference was the combination of the “old elements” into a single device by mounting them on a single chassis. The Court found that the operation of the heater was in no way dependent on the operation of the other equipment, and that a separate heater could also be used in conjunction with a standard paving machine to achieve the same results. The Court concluded that “[t]he convenience of putting the burner together with the other elements in one machine, though perhaps a matter of great convenience, did not produce a ‘new’ or ‘different function’” and that to those skilled in the art the use of the old elements in combination would have been obvious. Id. at 60, 163 USPQ at 674.

The claimed invention in Anderson’s-Black Rock, Inc. v. Pavement Salvage Co., 396 U.S. 57, 163 USPQ 673 (1969) was a paving machine which combined several well-known elements onto a single chassis. Standard prior art paving machines typically combined equipment for spreading and shaping asphalt onto a single chassis. The patent claim included the well-known element of a radiant-heat burner attached to the side of the paver for the purpose of preventing cold joints during continuous strip paving. The prior art used radiant heat for softening the asphalt to make patches, but did not use radiant heat burners to achieve continuous strip paving. All of the component parts were known in the prior art. The only difference was the combination of the “old elements” into a single device by mounting them on a single chassis. The Court found that the operation of the heater was in no way dependent on the operation of the other equipment, and that a separate heater could also be used in conjunction with a standard paving machine to achieve the same results. The Court concluded that “[t]he convenience of putting the burner together with the other elements in one machine, though perhaps a matter of great convenience, did not produce a ‘new’ or ‘different function’” and that to those skilled in the art the use of the old elements in combination would have been obvious. Id. at 60, 163 USPQ at 674.

The claimed invention in Anderson’s-Black Rock, Inc. v. Pavement Salvage Co., 396 U.S. 57, 163 USPQ 673 (1969) was a paving machine which combined several well-known elements onto a single chassis. Standard prior art paving machines typically combined equipment for spreading and shaping asphalt onto a single chassis. The patent claim included the well-known element of a radiant-heat burner attached to the side of the paver for the purpose of preventing cold joints during continuous strip paving. The prior art used radiant heat for softening the asphalt to make patches, but did not use radiant heat burners to achieve continuous strip paving. All of the component parts were known in the prior art. The only difference was the combination of the “old elements” into a single device by mounting them on a single chassis. The Court found that the operation of the heater was in no way dependent on the operation of the other equipment, and that a separate heater could also be used in conjunction with a standard paving machine to achieve the same results. The Court concluded that “[t]he convenience of putting the burner together with the other elements in one machine, though perhaps a matter of great convenience, did not produce a ‘new’ or ‘different function’” and that to those skilled in the art the use of the old elements in combination would have been obvious. Id. at 60, 163 USPQ at 674.

Note that combining known prior art elements is not sufficient to render the claimed invention obvious if the results would not have been predictable to one of ordinary skill in the art. United States v. Adams, 383 U.S. 39, 51-52, 148 USPQ 479, 483-84 (1966). In Adams, the claimed invention was to a battery with one magnesium electrode and one cuprous chloride electrode that could be stored dry and activated by the addition of plain water or salt water. Although magnesium and cuprous chloride were individually known battery components, the Court concluded that the claimed battery was nonobvious. The Court stated that “[d]espite the fact that each of the elements of the Adams battery was well known in the prior art, to combine them as did Adams required that a person reasonably skilled in the prior art must ignore” the teaching away of the prior art that such batteries were impractical and that water-activated batteries were successful only when combined with electrolytes detrimental to the use of magnesium electrodes. Id. at 42-43, 50-52, 148 USPQ at 480, 483. “[W]hen the prior art teaches away from combining certain known elements, discovery of successful means of combining them is more likely to be nonobvious.” KSR, 550 U.S. at 416, 82 USPQ2d at 1395.

Note that combining known prior art elements is not sufficient to render the claimed invention obvious if the results would not have been predictable to one of ordinary skill in the art. United States v. Adams, 383 U.S. 39, 51-52, 148 USPQ 479, 483-84 (1966). In Adams, the claimed invention was to a battery with one magnesium electrode and one cuprous chloride electrode that could be stored dry and activated by the addition of plain water or salt water. Although magnesium and cuprous chloride were individually known battery components, the Court concluded that the claimed battery was nonobvious. The Court stated that “[d]espite the fact that each of the elements of the Adams battery was well known in the prior art, to combine them as did Adams required that a person reasonably skilled in the prior art must ignore” the teaching away of the prior art that such batteries were impractical and that water-activated batteries were successful only when combined with electrolytes detrimental to the use of magnesium electrodes. Id. at 42-43, 50-52, 148 USPQ at 480, 483. “[W]hen the prior art teaches away from combining certain known elements, discovery of successful means of combining them is more likely to be nonobvious.” KSR, 550 U.S. at 416, 82 USPQ2d at 1395.

Note that combining known prior art elements is not sufficient to render the claimed invention obvious if the results would not have been predictable to one of ordinary skill in the art. United States v. Adams, 383 U.S. 39, 51-52, 148 USPQ 479, 483-84 (1966). In Adams, the claimed invention was to a battery with one magnesium electrode and one cuprous chloride electrode that could be stored dry and activated by the addition of plain water or salt water. Although magnesium and cuprous chloride were individually known battery components, the Court concluded that the claimed battery was nonobvious. The Court stated that “[d]espite the fact that each of the elements of the Adams battery was well known in the prior art, to combine them as did Adams required that a person reasonably skilled in the prior art must ignore” the teaching away of the prior art that such batteries were impractical and that water-activated batteries were successful only when combined with electrolytes detrimental to the use of magnesium electrodes. Id. at 42-43, 50-52, 148 USPQ at 480, 483. “[W]hen the prior art teaches away from combining certain known elements, discovery of successful means of combining them is more likely to be nonobvious.” KSR, 550 U.S. at 416, 82 USPQ2d at 1395.

The case of In re Omeprazole Patent Litigation, 536 F.3d 1361, 87 USPQ2d 1865 (Fed. Cir. 2008), is one in which the claims in question were found to be nonobvious in the context of an argument to combine prior art elements. The invention involved applying enteric coatings to a drug in pill form for the purpose of ensuring that the drug did not disintegrate before reaching its intended site of action. The drug at issue was omeprazole, the generic name for gastric acid inhibitor marketed as Prilosec ®. The claimed formulation included two layers of coatings over the active ingredient.

The case of In re Omeprazole Patent Litigation, 536 F.3d 1361, 87 USPQ2d 1865 (Fed. Cir. 2008), is one in which the claims in question were found to be nonobvious in the context of an argument to combine prior art elements. The invention involved applying enteric coatings to a drug in pill form for the purpose of ensuring that the drug did not disintegrate before reaching its intended site of action. The drug at issue was omeprazole, the generic name for gastric acid inhibitor marketed as Prilosec ®. The claimed formulation included two layers of coatings over the active ingredient.

The case of In re Omeprazole Patent Litigation, 536 F.3d 1361, 87 USPQ2d 1865 (Fed. Cir. 2008), is one in which the claims in question were found to be nonobvious in the context of an argument to combine prior art elements. The invention involved applying enteric coatings to a drug in pill form for the purpose of ensuring that the drug did not disintegrate before reaching its intended site of action. The drug at issue was omeprazole, the generic name for gastric acid inhibitor marketed as Prilosec ®. The claimed formulation included two layers of coatings over the active ingredient.

Office personnel should note that in this case the modification of the prior art that had been presented as an argument for obviousness was an extra process step that added an additional component to a known, successfully marketed formulation. The proposed modification thus amounted to extra work and greater expense for no apparent reason. This is not the same as combining known prior art elements A and B when each would have been expected to contribute its own known properties to the final product. In the Omeprazole case, in view of the expectations of those of ordinary skill in the art, adding the subcoating would not have been expected to confer any particular desirable property on the final product. Rather, the final product obtained according to the proposed modifications would merely have been expected to have the same functional properties as the prior art product.

Office personnel should note that in this case the modification of the prior art that had been presented as an argument for obviousness was an extra process step that added an additional component to a known, successfully marketed formulation. The proposed modification thus amounted to extra work and greater expense for no apparent reason. This is not the same as combining known prior art elements A and B when each would have been expected to contribute its own known properties to the final product. In the Omeprazole case, in view of the expectations of those of ordinary skill in the art, adding the subcoating would not have been expected to confer any particular desirable property on the final product. Rather, the final product obtained according to the proposed modifications would merely have been expected to have the same functional properties as the prior art product.

Office personnel should note that in this case the modification of the prior art that had been presented as an argument for obviousness was an extra process step that added an additional component to a known, successfully marketed formulation. The proposed modification thus amounted to extra work and greater expense for no apparent reason. This is not the same as combining known prior art elements A and B when each would have been expected to contribute its own known properties to the final product. In the Omeprazole case, in view of the expectations of those of ordinary skill in the art, adding the subcoating would not have been expected to confer any particular desirable property on the final product. Rather, the final product obtained according to the proposed modifications would merely have been expected to have the same functional properties as the prior art product.

The Omeprazole case can also be analyzed in view of the discovery of a previously unknown problem by the patentee. If the adverse interaction between active agent and coating had been known, it might well have been obvious to use a subcoating. However, since the problem had not been previously known, there would have been no reason to incur additional time and expense to add another layer, even though the addition would have been technologically possible. This is true because the prior art of record failed to mention any stability problem, despite the acknowledgment during testimony at trial that there was a known theoretical reason that omeprazole might be subject to degradation in the presence of the known coating material.

The Federal Circuit disagreed. The Federal Circuit stated that the prior art did not teach foam heel straps, or that a foam heel strap should be placed in contact with a foam base. The Federal Circuit pointed out that the prior art actually counseled against using foam as a material for the heel strap of a shoe.

The Federal Circuit disagreed. The Federal Circuit stated that the prior art did not teach foam heel straps, or that a foam heel strap should be placed in contact with a foam base. The Federal Circuit pointed out that the prior art actually counseled against using foam as a material for the heel strap of a shoe.

The Federal Circuit disagreed. The Federal Circuit stated that the prior art did not teach foam heel straps, or that a foam heel strap should be placed in contact with a foam base. The Federal Circuit pointed out that the prior art actually counseled against using foam as a material for the heel strap of a shoe.

The Federal Circuit’s discussion in Crocs serves as a reminder to Office personnel that merely pointing to the presence of all claim elements in the prior art is not a complete statement of a rejection for obviousness. In accordance with MPEP § 2143, subsection I.A.(3), a proper rejection based on the rationale that the claimed invention is a combination of prior art elements also includes a finding that results flowing from the combination would have been predictable to a person of ordinary skill in the art. MPEP § 2143, subsection I.A.(3). If results would not have been predictable, Office personnel should not enter an obviousness rejection using the combination of prior art elements rationale, and should withdraw such a rejection if it has been made.

Sundance, Inc. v. DeMonte Fabricating Ltd., 550 F.3d 1356, 89 USPQ2d 1535 (Fed. Cir. 2008), involved a segmented and mechanized cover for trucks, swimming pools, or other structures. The claim was found to be obvious over the prior art applied.

When considering the question of obviousness, Office personnel should keep in mind the capabilities of a person of ordinary skill. In Ecolab, the Federal Circuit stated:

The court then turned to the question of whether there would have been adequate motivation to combine the prior art elements as had been urged by Master Lock. The court recalled the Graham inquiries, and also emphasized the “expansive and flexible” post-KSR approach to obviousness that must not “deny factfinders recourse to common sense.” Id. at 1238, 95 USPQ2d at 1530-31. (quoting KSR, 550 U.S. at 415, 421, 82 USPQ2d at 1395, 1397). The court stated:

The court then turned to the question of whether there would have been adequate motivation to combine the prior art elements as had been urged by Master Lock. The court recalled the Graham inquiries, and also emphasized the “expansive and flexible” post-KSR approach to obviousness that must not “deny factfinders recourse to common sense.” Id. at 1238, 95 USPQ2d at 1530-31. (quoting KSR, 550 U.S. at 415, 421, 82 USPQ2d at 1395, 1397). The court stated:

The claim in DePuy Spine, Inc. v. Medtronic Sofamor Danek, Inc., 567 F.3d 1314, 90 USPQ2d 1865 (Fed. Cir. 2009), was directed to a polyaxial pedicle screw used in spinal surgeries that included a compression member for pressing a screw head against a receiver member. A prior art reference (Puno) disclosed all of the elements of the claim except for the compression member. Instead, the screw head in Puno was separated from the receiver member to achieve a shock absorber effect, allowing some motion between receiver member and the vertebrae. The missing compression member was readily found in another prior art reference (Anderson), which disclosed an external fracture immobilization splint for immobilizing long bones with a swivel clamp capable of polyaxial movement until rigidly secured by a compression member. It was asserted during trial that a person of ordinary skill would have recognized that the addition of Anderson’s compression member to Puno’s device would have achieved a rigidly locked polyaxial pedicle screw covered by the claim.

The claim in DePuy Spine, Inc. v. Medtronic Sofamor Danek, Inc., 567 F.3d 1314, 90 USPQ2d 1865 (Fed. Cir. 2009), was directed to a polyaxial pedicle screw used in spinal surgeries that included a compression member for pressing a screw head against a receiver member. A prior art reference (Puno) disclosed all of the elements of the claim except for the compression member. Instead, the screw head in Puno was separated from the receiver member to achieve a shock absorber effect, allowing some motion between receiver member and the vertebrae. The missing compression member was readily found in another prior art reference (Anderson), which disclosed an external fracture immobilization splint for immobilizing long bones with a swivel clamp capable of polyaxial movement until rigidly secured by a compression member. It was asserted during trial that a person of ordinary skill would have recognized that the addition of Anderson’s compression member to Puno’s device would have achieved a rigidly locked polyaxial pedicle screw covered by the claim.

The claim in DePuy Spine, Inc. v. Medtronic Sofamor Danek, Inc., 567 F.3d 1314, 90 USPQ2d 1865 (Fed. Cir. 2009), was directed to a polyaxial pedicle screw used in spinal surgeries that included a compression member for pressing a screw head against a receiver member. A prior art reference (Puno) disclosed all of the elements of the claim except for the compression member. Instead, the screw head in Puno was separated from the receiver member to achieve a shock absorber effect, allowing some motion between receiver member and the vertebrae. The missing compression member was readily found in another prior art reference (Anderson), which disclosed an external fracture immobilization splint for immobilizing long bones with a swivel clamp capable of polyaxial movement until rigidly secured by a compression member. It was asserted during trial that a person of ordinary skill would have recognized that the addition of Anderson’s compression member to Puno’s device would have achieved a rigidly locked polyaxial pedicle screw covered by the claim.

The claim in DePuy Spine, Inc. v. Medtronic Sofamor Danek, Inc., 567 F.3d 1314, 90 USPQ2d 1865 (Fed. Cir. 2009), was directed to a polyaxial pedicle screw used in spinal surgeries that included a compression member for pressing a screw head against a receiver member. A prior art reference (Puno) disclosed all of the elements of the claim except for the compression member. Instead, the screw head in Puno was separated from the receiver member to achieve a shock absorber effect, allowing some motion between receiver member and the vertebrae. The missing compression member was readily found in another prior art reference (Anderson), which disclosed an external fracture immobilization splint for immobilizing long bones with a swivel clamp capable of polyaxial movement until rigidly secured by a compression member. It was asserted during trial that a person of ordinary skill would have recognized that the addition of Anderson’s compression member to Puno’s device would have achieved a rigidly locked polyaxial pedicle screw covered by the claim.

The claimed invention in In re Fout, 675 F.2d 297, 213 USPQ 532 (CCPA 1982) was directed to a method for decaffeinating coffee or tea. The prior art (Pagliaro) method produced a decaffeinated vegetable material and trapped the caffeine in a fatty material (such as oil). The caffeine was then removed from the fatty material by an aqueous extraction process. Applicant (Fout) substituted an evaporative distillation step for the aqueous extraction step. The prior art (Waterman) suspended coffee in oil and then directly distilled the caffeine through the oil. The court found that “[b]ecause both Pagliaro and Waterman teach a method for separating caffeine from oil, it would have been prima facie obvious to substitute one method for the other. Express suggestion to substitute one equivalent for another need not be present to render such substitution obvious.” Id. at 301, 213 USPQ at 536.

The claimed invention in In re Fout, 675 F.2d 297, 213 USPQ 532 (CCPA 1982) was directed to a method for decaffeinating coffee or tea. The prior art (Pagliaro) method produced a decaffeinated vegetable material and trapped the caffeine in a fatty material (such as oil). The caffeine was then removed from the fatty material by an aqueous extraction process. Applicant (Fout) substituted an evaporative distillation step for the aqueous extraction step. The prior art (Waterman) suspended coffee in oil and then directly distilled the caffeine through the oil. The court found that “[b]ecause both Pagliaro and Waterman teach a method for separating caffeine from oil, it would have been prima facie obvious to substitute one method for the other. Express suggestion to substitute one equivalent for another need not be present to render such substitution obvious.” Id. at 301, 213 USPQ at 536.

The claimed invention in In re Fout, 675 F.2d 297, 213 USPQ 532 (CCPA 1982) was directed to a method for decaffeinating coffee or tea. The prior art (Pagliaro) method produced a decaffeinated vegetable material and trapped the caffeine in a fatty material (such as oil). The caffeine was then removed from the fatty material by an aqueous extraction process. Applicant (Fout) substituted an evaporative distillation step for the aqueous extraction step. The prior art (Waterman) suspended coffee in oil and then directly distilled the caffeine through the oil. The court found that “[b]ecause both Pagliaro and Waterman teach a method for separating caffeine from oil, it would have been prima facie obvious to substitute one method for the other. Express suggestion to substitute one equivalent for another need not be present to render such substitution obvious.” Id. at 301, 213 USPQ at 536.

The claimed invention in In re Fout, 675 F.2d 297, 213 USPQ 532 (CCPA 1982) was directed to a method for decaffeinating coffee or tea. The prior art (Pagliaro) method produced a decaffeinated vegetable material and trapped the caffeine in a fatty material (such as oil). The caffeine was then removed from the fatty material by an aqueous extraction process. Applicant (Fout) substituted an evaporative distillation step for the aqueous extraction step. The prior art (Waterman) suspended coffee in oil and then directly distilled the caffeine through the oil. The court found that “[b]ecause both Pagliaro and Waterman teach a method for separating caffeine from oil, it would have been prima facie obvious to substitute one method for the other. Express suggestion to substitute one equivalent for another need not be present to render such substitution obvious.” Id. at 301, 213 USPQ at 536.

The claimed invention in In re Fout, 675 F.2d 297, 213 USPQ 532 (CCPA 1982) was directed to a method for decaffeinating coffee or tea. The prior art (Pagliaro) method produced a decaffeinated vegetable material and trapped the caffeine in a fatty material (such as oil). The caffeine was then removed from the fatty material by an aqueous extraction process. Applicant (Fout) substituted an evaporative distillation step for the aqueous extraction step. The prior art (Waterman) suspended coffee in oil and then directly distilled the caffeine through the oil. The court found that “[b]ecause both Pagliaro and Waterman teach a method for separating caffeine from oil, it would have been prima facie obvious to substitute one method for the other. Express suggestion to substitute one equivalent for another need not be present to render such substitution obvious.” Id. at 301, 213 USPQ at 536.

The claimed invention in In re Fout, 675 F.2d 297, 213 USPQ 532 (CCPA 1982) was directed to a method for decaffeinating coffee or tea. The prior art (Pagliaro) method produced a decaffeinated vegetable material and trapped the caffeine in a fatty material (such as oil). The caffeine was then removed from the fatty material by an aqueous extraction process. Applicant (Fout) substituted an evaporative distillation step for the aqueous extraction step. The prior art (Waterman) suspended coffee in oil and then directly distilled the caffeine through the oil. The court found that “[b]ecause both Pagliaro and Waterman teach a method for separating caffeine from oil, it would have been prima facie obvious to substitute one method for the other. Express suggestion to substitute one equivalent for another need not be present to render such substitution obvious.” Id. at 301, 213 USPQ at 536.

The fact pattern in Ruiz v. AB Chance Co., 357 F.3d 1270, 69 USPQ2d 1686 (Fed. Cir. 2004) is set forth above in Example 2 in subsection I.A., above.

The claimed invention in Ex parte Smith, 83 USPQ2d 1509 (Bd. Pat. App. & Int. 2007), was a pocket insert for a bound book made by gluing a base sheet and a pocket sheet of paper together to form a continuous two-ply seam defining a closed pocket. The prior art (Wyant) disclosed at least one pocket formed by folding a single sheet and securing the folder portions along the inside margins using any convenient bonding method. The prior art (Wyant) did not disclose bonding the sheets to form a continuous two-ply seam. The prior art (Dick) disclosed a pocket that is made by stitching or otherwise securing two sheets along three of its four edges to define a closed pocket with an opening along its fourth edge.

The claimed invention in Ex parte Smith, 83 USPQ2d 1509 (Bd. Pat. App. & Int. 2007), was a pocket insert for a bound book made by gluing a base sheet and a pocket sheet of paper together to form a continuous two-ply seam defining a closed pocket. The prior art (Wyant) disclosed at least one pocket formed by folding a single sheet and securing the folder portions along the inside margins using any convenient bonding method. The prior art (Wyant) did not disclose bonding the sheets to form a continuous two-ply seam. The prior art (Dick) disclosed a pocket that is made by stitching or otherwise securing two sheets along three of its four edges to define a closed pocket with an opening along its fourth edge.

The claimed invention in Ex parte Smith, 83 USPQ2d 1509 (Bd. Pat. App. & Int. 2007), was a pocket insert for a bound book made by gluing a base sheet and a pocket sheet of paper together to form a continuous two-ply seam defining a closed pocket. The prior art (Wyant) disclosed at least one pocket formed by folding a single sheet and securing the folder portions along the inside margins using any convenient bonding method. The prior art (Wyant) did not disclose bonding the sheets to form a continuous two-ply seam. The prior art (Dick) disclosed a pocket that is made by stitching or otherwise securing two sheets along three of its four edges to define a closed pocket with an opening along its fourth edge.

The claimed invention in Ex parte Smith, 83 USPQ2d 1509 (Bd. Pat. App. & Int. 2007), was a pocket insert for a bound book made by gluing a base sheet and a pocket sheet of paper together to form a continuous two-ply seam defining a closed pocket. The prior art (Wyant) disclosed at least one pocket formed by folding a single sheet and securing the folder portions along the inside margins using any convenient bonding method. The prior art (Wyant) did not disclose bonding the sheets to form a continuous two-ply seam. The prior art (Dick) disclosed a pocket that is made by stitching or otherwise securing two sheets along three of its four edges to define a closed pocket with an opening along its fourth edge.

The claimed invention in In re ICON Health & Fitness, Inc., 496 F.3d 1374, 83 USPQ2d 1746 (Fed. Cir. 2007), was directed to a treadmill with a folding tread base that swivels into an upright storage position, including a gas spring connected between the tread base and the upright structure to assist in stably retaining the tread base in the storage position. On reexamination, the examiner rejected the claims as obvious based on a combination of references including an advertisement (Damark) for a folding treadmill demonstrating all of the claim elements other than the gas spring, and a patent (Teague) with a gas spring. Teague was directed to a bed that folds into a cabinet using a novel dual-action spring that reverses force as the mechanism passes a neutral position, rather than a single-action spring that would provide a force pushing the bed closed at all times. The dual-action spring reduced the force required to open the bed from the closed position, while reducing the force required to lift the bed from the open position.

The claimed invention in In re ICON Health & Fitness, Inc., 496 F.3d 1374, 83 USPQ2d 1746 (Fed. Cir. 2007), was directed to a treadmill with a folding tread base that swivels into an upright storage position, including a gas spring connected between the tread base and the upright structure to assist in stably retaining the tread base in the storage position. On reexamination, the examiner rejected the claims as obvious based on a combination of references including an advertisement (Damark) for a folding treadmill demonstrating all of the claim elements other than the gas spring, and a patent (Teague) with a gas spring. Teague was directed to a bed that folds into a cabinet using a novel dual-action spring that reverses force as the mechanism passes a neutral position, rather than a single-action spring that would provide a force pushing the bed closed at all times. The dual-action spring reduced the force required to open the bed from the closed position, while reducing the force required to lift the bed from the open position.

The claimed invention in In re ICON Health & Fitness, Inc., 496 F.3d 1374, 83 USPQ2d 1746 (Fed. Cir. 2007), was directed to a treadmill with a folding tread base that swivels into an upright storage position, including a gas spring connected between the tread base and the upright structure to assist in stably retaining the tread base in the storage position. On reexamination, the examiner rejected the claims as obvious based on a combination of references including an advertisement (Damark) for a folding treadmill demonstrating all of the claim elements other than the gas spring, and a patent (Teague) with a gas spring. Teague was directed to a bed that folds into a cabinet using a novel dual-action spring that reverses force as the mechanism passes a neutral position, rather than a single-action spring that would provide a force pushing the bed closed at all times. The dual-action spring reduced the force required to open the bed from the closed position, while reducing the force required to lift the bed from the open position.

ICON is another useful example for understanding the scope of analogous art. The art applied concerned retaining mechanisms for folding beds, not treadmills. When determining whether a reference may properly be applied to an invention in a different field of endeavor, it is necessary to consider the problem to be solved. It is certainly possible that a reference may be drawn in such a way that its usefulness as a teaching is narrowly restricted. However, in ICON, the problem to be solved was not limited to the teaching of the “treadmill” concept. The Teague reference was analogous art because “Teague and the current application both address the need to stably retain a folding mechanism,” and because “nothing about ICON’s folding mechanism requires any particular focus on treadmills,” Id. at 1378, 1380, 83 USPQ2d at 1749-50.

The Federal Circuit’s discussion in ICON also makes clear that if the reference does not teach that a combination is undesirable, then it cannot be said to teach away. An assessment of whether a combination would render the device inoperable must not “ignore the modifications that one skilled in the art would make to a device borrowed from the prior art.” Id. at 1382, 83 USPQ2d at 1752.

The Federal Circuit’s discussion in ICON also makes clear that if the reference does not teach that a combination is undesirable, then it cannot be said to teach away. An assessment of whether a combination would render the device inoperable must not “ignore the modifications that one skilled in the art would make to a device borrowed from the prior art.” Id. at 1382, 83 USPQ2d at 1752.

The Federal Circuit’s discussion in ICON also makes clear that if the reference does not teach that a combination is undesirable, then it cannot be said to teach away. An assessment of whether a combination would render the device inoperable must not “ignore the modifications that one skilled in the art would make to a device borrowed from the prior art.” Id. at 1382, 83 USPQ2d at 1752.

Agrizap, Inc. v. Woodstream Corp., 520 F.3d 1337, 86 USPQ2d 1110 (Fed. Cir. 2008), involved a stationary pest control device for electrocution of pests such as rats and gophers, in which the device is set in an area where the pest is likely to encounter it. The only difference between the claimed device and the prior art stationary pest control device was that the claimed device employed a resistive electrical switch, while the prior art device used a mechanical pressure switch. A resistive electrical switch was taught in two prior art patents, in the contexts of a hand-held pest control device and a cattle prod.

Agrizap, Inc. v. Woodstream Corp., 520 F.3d 1337, 86 USPQ2d 1110 (Fed. Cir. 2008), involved a stationary pest control device for electrocution of pests such as rats and gophers, in which the device is set in an area where the pest is likely to encounter it. The only difference between the claimed device and the prior art stationary pest control device was that the claimed device employed a resistive electrical switch, while the prior art device used a mechanical pressure switch. A resistive electrical switch was taught in two prior art patents, in the contexts of a hand-held pest control device and a cattle prod.

Agrizap, Inc. v. Woodstream Corp., 520 F.3d 1337, 86 USPQ2d 1110 (Fed. Cir. 2008), involved a stationary pest control device for electrocution of pests such as rats and gophers, in which the device is set in an area where the pest is likely to encounter it. The only difference between the claimed device and the prior art stationary pest control device was that the claimed device employed a resistive electrical switch, while the prior art device used a mechanical pressure switch. A resistive electrical switch was taught in two prior art patents, in the contexts of a hand-held pest control device and a cattle prod.

In Aventis Pharma Deutschland v. Lupin Ltd., 499 F.3d 1293, 84 USPQ2d 1197 (Fed. Cir. 2007), the claims were drawn to the 5(S) stereoisomer of the blood pressure drug ramipril in stereochemically pure form, and to compositions and methods requiring 5(S) ramipril. The 5(S) stereoisomer is one in which all five stereocenters in the ramipril molecule are in the S rather than the R configuration. A mixture of various stereoisomers including 5(S) ramipril had been taught by the prior art. The question before the court was whether the purified single stereoisomer would have been obvious over the known mixture of stereoisomers.

In Aventis Pharma Deutschland v. Lupin Ltd., 499 F.3d 1293, 84 USPQ2d 1197 (Fed. Cir. 2007), the claims were drawn to the 5(S) stereoisomer of the blood pressure drug ramipril in stereochemically pure form, and to compositions and methods requiring 5(S) ramipril. The 5(S) stereoisomer is one in which all five stereocenters in the ramipril molecule are in the S rather than the R configuration. A mixture of various stereoisomers including 5(S) ramipril had been taught by the prior art. The question before the court was whether the purified single stereoisomer would have been obvious over the known mixture of stereoisomers.

In Aventis Pharma Deutschland v. Lupin Ltd., 499 F.3d 1293, 84 USPQ2d 1197 (Fed. Cir. 2007), the claims were drawn to the 5(S) stereoisomer of the blood pressure drug ramipril in stereochemically pure form, and to compositions and methods requiring 5(S) ramipril. The 5(S) stereoisomer is one in which all five stereocenters in the ramipril molecule are in the S rather than the R configuration. A mixture of various stereoisomers including 5(S) ramipril had been taught by the prior art. The question before the court was whether the purified single stereoisomer would have been obvious over the known mixture of stereoisomers.

Id. at 1301, 84 USPQ2d at 1204. The Aventis court also relied on the settled principle that in chemical cases, structural similarity can provide the necessary reason to modify prior art teachings. The Federal Circuit also addressed the kind of teaching that would be sufficient in the absence of an explicitly stated prior art-based motivation, explaining that an expectation of similar properties in light of the prior art can be sufficient, even without an explicit teaching that the compound will have a particular utility.

Obviousness based on structural similarity thus can be proved by identification of some motivation that would have led one of ordinary skill in the art to select and then modify a known compound (i.e. a lead compound) in a particular way to achieve the claimed compound…. In keeping with the flexible nature of the obviousness inquiry, the requisite motivation can come from any number of sources and need not necessarily be explicit in the art. Rather “it is sufficient to show that the claimed and prior art compounds possess a ‘sufficiently close relationship… to create an expectation,’ in light of the totality of the prior art, that the new compound will have ‘similar properties’ to the old.” Id. at 1357, 87 USPQ2d at 1455. (citations omitted)

Obviousness based on structural similarity thus can be proved by identification of some motivation that would have led one of ordinary skill in the art to select and then modify a known compound (i.e. a lead compound) in a particular way to achieve the claimed compound…. In keeping with the flexible nature of the obviousness inquiry, the requisite motivation can come from any number of sources and need not necessarily be explicit in the art. Rather “it is sufficient to show that the claimed and prior art compounds possess a ‘sufficiently close relationship… to create an expectation,’ in light of the totality of the prior art, that the new compound will have ‘similar properties’ to the old.” Id. at 1357, 87 USPQ2d at 1455. (citations omitted)

Office personnel are cautioned that the term “lead compound” in a particular opinion can have a contextual meaning that may vary from the way a pharmaceutical chemist might use the term. In the field of pharmaceutical chemistry, the term “lead compound” has been defined variously as “a chemical compound that has pharmacological or biological activity and whose chemical structure is used as a starting point for chemical modifications in order to improve potency, selectivity, or pharmacokinetic parameters;” “[a] compound that exhibits pharmacological properties which suggest its development;” and “a potential drug being tested for safety and efficacy.” See, e.g., http://en.wikipedia.org/wiki/Lead_compound, accessed January 13, 2010; www.combichemistry.com/glossary_k.html, accessed January 13, 2010; and www.buildingbiotechnology.com/glossary4.php, accessed January 13, 2010.

Office personnel are cautioned that the term “lead compound” in a particular opinion can have a contextual meaning that may vary from the way a pharmaceutical chemist might use the term. In the field of pharmaceutical chemistry, the term “lead compound” has been defined variously as “a chemical compound that has pharmacological or biological activity and whose chemical structure is used as a starting point for chemical modifications in order to improve potency, selectivity, or pharmacokinetic parameters;” “[a] compound that exhibits pharmacological properties which suggest its development;” and “a potential drug being tested for safety and efficacy.” See, e.g., http://en.wikipedia.org/wiki/Lead_compound, accessed January 13, 2010; www.combichemistry.com/glossary_k.html, accessed January 13, 2010; and www.buildingbiotechnology.com/glossary4.php, accessed January 13, 2010.

Office personnel are cautioned that the term “lead compound” in a particular opinion can have a contextual meaning that may vary from the way a pharmaceutical chemist might use the term. In the field of pharmaceutical chemistry, the term “lead compound” has been defined variously as “a chemical compound that has pharmacological or biological activity and whose chemical structure is used as a starting point for chemical modifications in order to improve potency, selectivity, or pharmacokinetic parameters;” “[a] compound that exhibits pharmacological properties which suggest its development;” and “a potential drug being tested for safety and efficacy.” See, e.g., http://en.wikipedia.org/wiki/Lead_compound, accessed January 13, 2010; www.combichemistry.com/glossary_k.html, accessed January 13, 2010; and www.buildingbiotechnology.com/glossary4.php, accessed January 13, 2010.

The Federal Circuit in Eisai makes it clear that from the perspective of the law of obviousness, any known compound might possibly serve as a lead compound: “Obviousness based on structural similarity thus can be proved by identification of some motivation that would have led one of ordinary skill in the art to select and then modify a known compound (i.e. a lead compound) in a particular way to achieve the claimed compound.” Eisai, 533 F.3d at 1357, 87 USPQ2d at 1455. Thus, Office personnel should recognize that a proper obviousness rejection of a claimed compound that is useful as a drug might be made beginning with an inactive compound, if, for example, the reasons for modifying a prior art compound to arrive at the claimed compound have nothing to do with pharmaceutical activity. The inactive compound would not be considered to be a lead compound by pharmaceutical chemists, but could potentially be used as such when considering obviousness. Office personnel might also base an obviousness rejection on a known compound that pharmaceutical chemists would not select as a lead compound due to expense, handling issues, or other business considerations. However, there must be some reason for starting with that particular lead compound other than the mere fact that the “lead compound” exists. See Altana Pharma AG v. Teva Pharm. USA, Inc., 566 F.3d 999, 1007, 91 USPQ2d 1018, 1024 (Fed. Cir. 2009) (holding that there must be some reason “to select and modify a known compound”); Ortho-McNeil Pharm., Inc. v. Mylan Labs, Inc., 520 F.3d 1358, 1364, 86 USPQ2d 1196, 1201 (Fed. Cir. 2008).

The Federal Circuit affirmed the district court’s decision. The Federal Circuit did not deem it necessary in this case to consider the question of whether 2-pyr EHDP had been appropriately selected as a lead compound. Rather, the Federal Circuit reasoned that, if 2-pyr EHDP is presumed to be an appropriate lead compound, there must be both a reason to modify it so as to make risedronate and a reasonable expectation of success. Here, there was no evidence that the necessary modifications would have been routine, so there would have been no reasonable expectation of success.

The Federal Circuit affirmed the district court’s decision. The Federal Circuit did not deem it necessary in this case to consider the question of whether 2-pyr EHDP had been appropriately selected as a lead compound. Rather, the Federal Circuit reasoned that, if 2-pyr EHDP is presumed to be an appropriate lead compound, there must be both a reason to modify it so as to make risedronate and a reasonable expectation of success. Here, there was no evidence that the necessary modifications would have been routine, so there would have been no reasonable expectation of success.

The Federal Circuit affirmed the district court’s decision. The Federal Circuit did not deem it necessary in this case to consider the question of whether 2-pyr EHDP had been appropriately selected as a lead compound. Rather, the Federal Circuit reasoned that, if 2-pyr EHDP is presumed to be an appropriate lead compound, there must be both a reason to modify it so as to make risedronate and a reasonable expectation of success. Here, there was no evidence that the necessary modifications would have been routine, so there would have been no reasonable expectation of success.

The Federal Circuit affirmed the district court’s decision. The Federal Circuit did not deem it necessary in this case to consider the question of whether 2-pyr EHDP had been appropriately selected as a lead compound. Rather, the Federal Circuit reasoned that, if 2-pyr EHDP is presumed to be an appropriate lead compound, there must be both a reason to modify it so as to make risedronate and a reasonable expectation of success. Here, there was no evidence that the necessary modifications would have been routine, so there would have been no reasonable expectation of success.

The Federal Circuit noted in dicta that even if a prima facie case of obviousness had been established, sufficient evidence of unexpected results was introduced to rebut such a showing. At trial, the witnesses consistently testified that the properties of risedronate were not expected, offering evidence that researchers did not predict either the potency or the low dose at which the compound was effective. Tests comparing risedronate to a compound in the prior art reference showed that risedronate outperformed the other compound by a substantial margin, could be administered in a greater amount without an observable toxic effect, and was not lethal at the same levels as the other compound. The weight of the evidence and the credibility of the witnesses were sufficient to show unexpected results that would have rebutted an obviousness determination. Thus, nonobviousness can be shown when a claimed invention is shown to have unexpectedly superior properties when compared to the prior art.

The Federal Circuit noted in dicta that even if a prima facie case of obviousness had been established, sufficient evidence of unexpected results was introduced to rebut such a showing. At trial, the witnesses consistently testified that the properties of risedronate were not expected, offering evidence that researchers did not predict either the potency or the low dose at which the compound was effective. Tests comparing risedronate to a compound in the prior art reference showed that risedronate outperformed the other compound by a substantial margin, could be administered in a greater amount without an observable toxic effect, and was not lethal at the same levels as the other compound. The weight of the evidence and the credibility of the witnesses were sufficient to show unexpected results that would have rebutted an obviousness determination. Thus, nonobviousness can be shown when a claimed invention is shown to have unexpectedly superior properties when compared to the prior art.

The Federal Circuit noted in dicta that even if a prima facie case of obviousness had been established, sufficient evidence of unexpected results was introduced to rebut such a showing. At trial, the witnesses consistently testified that the properties of risedronate were not expected, offering evidence that researchers did not predict either the potency or the low dose at which the compound was effective. Tests comparing risedronate to a compound in the prior art reference showed that risedronate outperformed the other compound by a substantial margin, could be administered in a greater amount without an observable toxic effect, and was not lethal at the same levels as the other compound. The weight of the evidence and the credibility of the witnesses were sufficient to show unexpected results that would have rebutted an obviousness determination. Thus, nonobviousness can be shown when a claimed invention is shown to have unexpectedly superior properties when compared to the prior art.

It should be noted that the lead compound cases do not stand for the proposition that identification of a single lead compound is necessary in every obviousness rejection of a chemical compound. For example, one might envision a suggestion in the prior art to formulate a compound having certain structurally defined moieties, or moieties with certain properties. If a person of ordinary skill would have known how to synthesize such a compound, and the structural and/or functional result could reasonably have been predicted, then a prima facie case of obviousness of the claimed chemical compound might exist even without identification of a particular lead compound. As a second example, it could be possible to view a claimed compound as consisting of two known compounds attached via a chemical linker. The claimed compound might properly be found to have been obvious if there would have been a reason to link the two, if one of ordinary skill would have known how to do so, and if the resulting compound would have been the predictable result of the linkage procedure. Thus, Office personnel should recognize that in certain situations, it may be proper to reject a claimed chemical compound as obvious even without identifying a single lead compound.

It should be noted that the lead compound cases do not stand for the proposition that identification of a single lead compound is necessary in every obviousness rejection of a chemical compound. For example, one might envision a suggestion in the prior art to formulate a compound having certain structurally defined moieties, or moieties with certain properties. If a person of ordinary skill would have known how to synthesize such a compound, and the structural and/or functional result could reasonably have been predicted, then a prima facie case of obviousness of the claimed chemical compound might exist even without identification of a particular lead compound. As a second example, it could be possible to view a claimed compound as consisting of two known compounds attached via a chemical linker. The claimed compound might properly be found to have been obvious if there would have been a reason to link the two, if one of ordinary skill would have known how to do so, and if the resulting compound would have been the predictable result of the linkage procedure. Thus, Office personnel should recognize that in certain situations, it may be proper to reject a claimed chemical compound as obvious even without identifying a single lead compound.

Obviousness of a chemical compound in view of its structural similarity to a prior art compound may be shown by identifying some line of reasoning that would have led one of ordinary skill in the art to select and modify the prior art compound in a particular way to produce the claimed compound. The necessary line of reasoning can be drawn from any number of sources and need not necessarily be explicitly found in the prior art of record. The Federal Circuit determined that ample evidence supported the district court’s finding that compound 12 was a natural choice for further development. For example, Altana’s prior art patent claimed that its compounds, including compound 12, were improvements over the prior art; compound 12 was disclosed as one of the more potent of the eighteen compounds disclosed; the patent examiner had considered the compounds of Altana’s prior art patent to be relevant during the prosecution of the patent in suit; and experts had opined that one of ordinary skill in the art would have selected the eighteen compounds to pursue further investigation into their potential as proton pump inhibitors.

Obviousness of a chemical compound in view of its structural similarity to a prior art compound may be shown by identifying some line of reasoning that would have led one of ordinary skill in the art to select and modify the prior art compound in a particular way to produce the claimed compound. The necessary line of reasoning can be drawn from any number of sources and need not necessarily be explicitly found in the prior art of record. The Federal Circuit determined that ample evidence supported the district court’s finding that compound 12 was a natural choice for further development. For example, Altana’s prior art patent claimed that its compounds, including compound 12, were improvements over the prior art; compound 12 was disclosed as one of the more potent of the eighteen compounds disclosed; the patent examiner had considered the compounds of Altana’s prior art patent to be relevant during the prosecution of the patent in suit; and experts had opined that one of ordinary skill in the art would have selected the eighteen compounds to pursue further investigation into their potential as proton pump inhibitors.

Obviousness of a chemical compound in view of its structural similarity to a prior art compound may be shown by identifying some line of reasoning that would have led one of ordinary skill in the art to select and modify the prior art compound in a particular way to produce the claimed compound. The necessary line of reasoning can be drawn from any number of sources and need not necessarily be explicitly found in the prior art of record. The Federal Circuit determined that ample evidence supported the district court’s finding that compound 12 was a natural choice for further development. For example, Altana’s prior art patent claimed that its compounds, including compound 12, were improvements over the prior art; compound 12 was disclosed as one of the more potent of the eighteen compounds disclosed; the patent examiner had considered the compounds of Altana’s prior art patent to be relevant during the prosecution of the patent in suit; and experts had opined that one of ordinary skill in the art would have selected the eighteen compounds to pursue further investigation into their potential as proton pump inhibitors.

In response to Altana’s argument that the prior art must point to only a single lead compound for further development, the Federal Circuit stated that a “restrictive view of the lead compound test would present a rigid test similar to the teaching-suggestion-motivation test that the Supreme Court explicitly rejected in KSR…. The district court in this case employed a flexible approach – one that was admittedly preliminary – and found that the defendants had raised a substantial question that one of skill in the art would have used the more potent compounds of [Altana’s prior art] patent, including compound 12, as a starting point from which to pursue further development efforts. That finding was not clearly erroneous.” Id. at 1008, 91 USPQ2d at 1025.

In response to Altana’s argument that the prior art must point to only a single lead compound for further development, the Federal Circuit stated that a “restrictive view of the lead compound test would present a rigid test similar to the teaching-suggestion-motivation test that the Supreme Court explicitly rejected in KSR…. The district court in this case employed a flexible approach – one that was admittedly preliminary – and found that the defendants had raised a substantial question that one of skill in the art would have used the more potent compounds of [Altana’s prior art] patent, including compound 12, as a starting point from which to pursue further development efforts. That finding was not clearly erroneous.” Id. at 1008, 91 USPQ2d at 1025.

In response to Altana’s argument that the prior art must point to only a single lead compound for further development, the Federal Circuit stated that a “restrictive view of the lead compound test would present a rigid test similar to the teaching-suggestion-motivation test that the Supreme Court explicitly rejected in KSR…. The district court in this case employed a flexible approach – one that was admittedly preliminary – and found that the defendants had raised a substantial question that one of skill in the art would have used the more potent compounds of [Altana’s prior art] patent, including compound 12, as a starting point from which to pursue further development efforts. That finding was not clearly erroneous.” Id. at 1008, 91 USPQ2d at 1025.

In response to Altana’s argument that the prior art must point to only a single lead compound for further development, the Federal Circuit stated that a “restrictive view of the lead compound test would present a rigid test similar to the teaching-suggestion-motivation test that the Supreme Court explicitly rejected in KSR…. The district court in this case employed a flexible approach – one that was admittedly preliminary – and found that the defendants had raised a substantial question that one of skill in the art would have used the more potent compounds of [Altana’s prior art] patent, including compound 12, as a starting point from which to pursue further development efforts. That finding was not clearly erroneous.” Id. at 1008, 91 USPQ2d at 1025.

The Supreme Court in KSR noted that if the actual application of the technique would have been beyond the skill of one of ordinary skill in the art, then using the technique would not have been obvious. KSR, 550 U.S. at 417, 82 USPQ2d at 1396. If any of these findings cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.

The claimed invention in In re Nilssen, 851 F.2d 1401, 7 USPQ2d 1500 (Fed. Cir. 1988) was directed to a “means by which the self-oscillating inverter in a power-line-operated inverter-type fluorescent lamp ballast is disabled in case the output current from the inverter exceeds some pre-established threshold level for more than a very brief period.” Id. at 1402, 7 USPQ2d at 1501 That is, the current output was monitored, and if the current output exceeded some threshold for a specified short time, an actuation signal was sent and the inverter was disabled to protect it from damage.

The claimed invention in In re Nilssen, 851 F.2d 1401, 7 USPQ2d 1500 (Fed. Cir. 1988) was directed to a “means by which the self-oscillating inverter in a power-line-operated inverter-type fluorescent lamp ballast is disabled in case the output current from the inverter exceeds some pre-established threshold level for more than a very brief period.” Id. at 1402, 7 USPQ2d at 1501 That is, the current output was monitored, and if the current output exceeded some threshold for a specified short time, an actuation signal was sent and the inverter was disabled to protect it from damage.

The fact pattern in Ruiz v. AB Chance Co., 357 F.3d 1270, 69 USPQ2d 1686 (Fed. Cir. 2004) is set forth above in Example 2 in subsection I.A.

The nature of the problem to be solved may lead inventors to look at references relating to possible solutions to that problem. Id. at 1277, 69 USPQ2d at 1691. Therefore, it would have been obvious to use a metal bracket (as shown in Gregory) with the screw anchor (as shown in Fuller) to underpin unstable foundations.

The rationale to support a conclusion that the claim would have been obvious is that a particular known technique was recognized as part of the ordinary capabilities of one skilled in the art. One of ordinary skill in the art would have been capable of applying this known technique to a known device (method, or product) that was ready for improvement and the results would have been predictable to one of ordinary skill in the art. If any of these findings cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.

The claimed invention in Dann v. Johnston, 425 U.S. 219, 189 USPQ 257 (1976) was directed towards a system (i.e., computer) for automatic record keeping of bank checks and deposits. In this system, a customer would put a numerical category code on each check or deposit slip. The check processing system would record these on the check in magnetic ink, just as it does for amount and account information. With this system in place, the bank can provide statements to customers that are broken down to give subtotals for each category. The claimed system also allowed the bank to print reports according to a style requested by the customer. As characterized by the Court, “[u]nder respondent’s invention, then, a general purpose computer is programmed to provide bank customers with an individualized and categorized breakdown of their transactions during the period in question.” Id. at 222, 189 USPQ at 259.

The claimed invention in Dann v. Johnston, 425 U.S. 219, 189 USPQ 257 (1976) was directed towards a system (i.e., computer) for automatic record keeping of bank checks and deposits. In this system, a customer would put a numerical category code on each check or deposit slip. The check processing system would record these on the check in magnetic ink, just as it does for amount and account information. With this system in place, the bank can provide statements to customers that are broken down to give subtotals for each category. The claimed system also allowed the bank to print reports according to a style requested by the customer. As characterized by the Court, “[u]nder respondent’s invention, then, a general purpose computer is programmed to provide bank customers with an individualized and categorized breakdown of their transactions during the period in question.” Id. at 222, 189 USPQ at 259.

The claimed invention in Dann v. Johnston, 425 U.S. 219, 189 USPQ 257 (1976) was directed towards a system (i.e., computer) for automatic record keeping of bank checks and deposits. In this system, a customer would put a numerical category code on each check or deposit slip. The check processing system would record these on the check in magnetic ink, just as it does for amount and account information. With this system in place, the bank can provide statements to customers that are broken down to give subtotals for each category. The claimed system also allowed the bank to print reports according to a style requested by the customer. As characterized by the Court, “[u]nder respondent’s invention, then, a general purpose computer is programmed to provide bank customers with an individualized and categorized breakdown of their transactions during the period in question.” Id. at 222, 189 USPQ at 259.

The claimed invention in Dann v. Johnston, 425 U.S. 219, 189 USPQ 257 (1976) was directed towards a system (i.e., computer) for automatic record keeping of bank checks and deposits. In this system, a customer would put a numerical category code on each check or deposit slip. The check processing system would record these on the check in magnetic ink, just as it does for amount and account information. With this system in place, the bank can provide statements to customers that are broken down to give subtotals for each category. The claimed system also allowed the bank to print reports according to a style requested by the customer. As characterized by the Court, “[u]nder respondent’s invention, then, a general purpose computer is programmed to provide bank customers with an individualized and categorized breakdown of their transactions during the period in question.” Id. at 222, 189 USPQ at 259.

The claimed invention in Dann v. Johnston, 425 U.S. 219, 189 USPQ 257 (1976) was directed towards a system (i.e., computer) for automatic record keeping of bank checks and deposits. In this system, a customer would put a numerical category code on each check or deposit slip. The check processing system would record these on the check in magnetic ink, just as it does for amount and account information. With this system in place, the bank can provide statements to customers that are broken down to give subtotals for each category. The claimed system also allowed the bank to print reports according to a style requested by the customer. As characterized by the Court, “[u]nder respondent’s invention, then, a general purpose computer is programmed to provide bank customers with an individualized and categorized breakdown of their transactions during the period in question.” Id. at 222, 189 USPQ at 259.

The claimed invention in Dann v. Johnston, 425 U.S. 219, 189 USPQ 257 (1976) was directed towards a system (i.e., computer) for automatic record keeping of bank checks and deposits. In this system, a customer would put a numerical category code on each check or deposit slip. The check processing system would record these on the check in magnetic ink, just as it does for amount and account information. With this system in place, the bank can provide statements to customers that are broken down to give subtotals for each category. The claimed system also allowed the bank to print reports according to a style requested by the customer. As characterized by the Court, “[u]nder respondent’s invention, then, a general purpose computer is programmed to provide bank customers with an individualized and categorized breakdown of their transactions during the period in question.” Id. at 222, 189 USPQ at 259.

The claimed invention in Dann v. Johnston, 425 U.S. 219, 189 USPQ 257 (1976) was directed towards a system (i.e., computer) for automatic record keeping of bank checks and deposits. In this system, a customer would put a numerical category code on each check or deposit slip. The check processing system would record these on the check in magnetic ink, just as it does for amount and account information. With this system in place, the bank can provide statements to customers that are broken down to give subtotals for each category. The claimed system also allowed the bank to print reports according to a style requested by the customer. As characterized by the Court, “[u]nder respondent’s invention, then, a general purpose computer is programmed to provide bank customers with an individualized and categorized breakdown of their transactions during the period in question.” Id. at 222, 189 USPQ at 259.

KNOWN TECHNIQUE – This is an application of a technique from the prior art – the use of account numbers (generally used to track an individual's total transactions) to solve the problem of how to track categories of expenditures to more finely account for a budget. That is, account numbers (identifying data capable of processing in the automatic data processing system) were used to distinguish between different customers. Furthermore, banks have long segregated debits attributable to service charges within any given separate account and have rendered their customers subtotals for those charges. Previously, one would have needed to set up separate accounts for each category and thus receive separate reports. Supplementing the account information with additional digits (the category codes) solved the problem by effectively creating a single account that can be treated as distinct accounts for tracking and reporting services. That is, the category code merely allowed what might previously have been separate accounts to be handled as a single account, but with a number of sub-accounts indicated in the report.

KNOWN TECHNIQUE – This is an application of a technique from the prior art – the use of account numbers (generally used to track an individual's total transactions) to solve the problem of how to track categories of expenditures to more finely account for a budget. That is, account numbers (identifying data capable of processing in the automatic data processing system) were used to distinguish between different customers. Furthermore, banks have long segregated debits attributable to service charges within any given separate account and have rendered their customers subtotals for those charges. Previously, one would have needed to set up separate accounts for each category and thus receive separate reports. Supplementing the account information with additional digits (the category codes) solved the problem by effectively creating a single account that can be treated as distinct accounts for tracking and reporting services. That is, the category code merely allowed what might previously have been separate accounts to be handled as a single account, but with a number of sub-accounts indicated in the report.

KNOWN TECHNIQUE – This is an application of a technique from the prior art – the use of account numbers (generally used to track an individual's total transactions) to solve the problem of how to track categories of expenditures to more finely account for a budget. That is, account numbers (identifying data capable of processing in the automatic data processing system) were used to distinguish between different customers. Furthermore, banks have long segregated debits attributable to service charges within any given separate account and have rendered their customers subtotals for those charges. Previously, one would have needed to set up separate accounts for each category and thus receive separate reports. Supplementing the account information with additional digits (the category codes) solved the problem by effectively creating a single account that can be treated as distinct accounts for tracking and reporting services. That is, the category code merely allowed what might previously have been separate accounts to be handled as a single account, but with a number of sub-accounts indicated in the report.

KNOWN TECHNIQUE – This is an application of a technique from the prior art – the use of account numbers (generally used to track an individual's total transactions) to solve the problem of how to track categories of expenditures to more finely account for a budget. That is, account numbers (identifying data capable of processing in the automatic data processing system) were used to distinguish between different customers. Furthermore, banks have long segregated debits attributable to service charges within any given separate account and have rendered their customers subtotals for those charges. Previously, one would have needed to set up separate accounts for each category and thus receive separate reports. Supplementing the account information with additional digits (the category codes) solved the problem by effectively creating a single account that can be treated as distinct accounts for tracking and reporting services. That is, the category code merely allowed what might previously have been separate accounts to be handled as a single account, but with a number of sub-accounts indicated in the report.

The fact pattern in In re Nilssen, 851 F.2d 1401, 7 USPQ2d 1500 (Fed. Cir. 1988) is set forth above in Example 1 in subsection C.

The claimed invention in In re Urbanski, 809 F.3d 1237, 1244, 117 USPQ2d 1499, 1504 (Fed. Cir. 2016) was directed to a method of enzymatic hydrolysis of soy fiber to reduce water holding capacity, requiring reacting the soy fiber and enzyme in water for about 60-120 minutes. The claims were rejected over two references, wherein the primary reference, Gross, taught using a reaction time of 5 to 72 hours and the secondary reference, Wong, taught using a reaction time of 100 to 240 minutes, preferably 120 minutes. The applicant argued that modifying the primary reference in the manner suggested by the secondary reference would forego the benefits taught by the primary reference, thereby teaching away from the combination. The court found there was sufficient motivation to combine because both references recognized reaction time and degree of hydrolysis as result-effective variables, which can be varied to have a predictable effect on the final product; and the primary reference does not contain an express teaching away from the proposed modification. “Substantial evidence thus supports the Board’s finding that a person of ordinary skill would have been motivated to modify the Gross process by using a shorter reaction time, in order to obtain the favorable properties disclosed in Wong.”

The claimed invention in In re Urbanski, 809 F.3d 1237, 1244, 117 USPQ2d 1499, 1504 (Fed. Cir. 2016) was directed to a method of enzymatic hydrolysis of soy fiber to reduce water holding capacity, requiring reacting the soy fiber and enzyme in water for about 60-120 minutes. The claims were rejected over two references, wherein the primary reference, Gross, taught using a reaction time of 5 to 72 hours and the secondary reference, Wong, taught using a reaction time of 100 to 240 minutes, preferably 120 minutes. The applicant argued that modifying the primary reference in the manner suggested by the secondary reference would forego the benefits taught by the primary reference, thereby teaching away from the combination. The court found there was sufficient motivation to combine because both references recognized reaction time and degree of hydrolysis as result-effective variables, which can be varied to have a predictable effect on the final product; and the primary reference does not contain an express teaching away from the proposed modification. “Substantial evidence thus supports the Board’s finding that a person of ordinary skill would have been motivated to modify the Gross process by using a shorter reaction time, in order to obtain the favorable properties disclosed in Wong.”

The question of whether a claimed invention can be shown to be obvious based on an “obvious to try” line of reasoning has been explored extensively by the Federal Circuit in several cases since the KSR decision. The case law in this area is developing quickly in the chemical arts, although the rationale has been applied in other art areas as well.

The Federal Circuit pointed out the challenging nature of the task faced by the courts – and likewise by Office personnel – when considering the viability of an obvious to try argument: “The evaluation of the choices made by a skilled scientist, when such choices lead to the desired result, is a challenge to judicial understanding of how technical advance is achieved in the particular field of science or technology.” Abbott Labs. v. Sandoz, Inc., 544 F.3d 1341, 1352, 89 USPQ2d 1161, 1171 (Fed. Cir. 2008). The Federal Circuit cautioned that an obviousness inquiry based on an obvious to try rationale must always be undertaken in the context of the subject matter in question, “including the characteristics of the science or technology, its state of advance, the nature of the known choices, the specificity or generality of the prior art, and the predictability of results in the area of interest.” Id.

The Federal Circuit pointed out the challenging nature of the task faced by the courts – and likewise by Office personnel – when considering the viability of an obvious to try argument: “The evaluation of the choices made by a skilled scientist, when such choices lead to the desired result, is a challenge to judicial understanding of how technical advance is achieved in the particular field of science or technology.” Abbott Labs. v. Sandoz, Inc., 544 F.3d 1341, 1352, 89 USPQ2d 1161, 1171 (Fed. Cir. 2008). The Federal Circuit cautioned that an obviousness inquiry based on an obvious to try rationale must always be undertaken in the context of the subject matter in question, “including the characteristics of the science or technology, its state of advance, the nature of the known choices, the specificity or generality of the prior art, and the predictability of results in the area of interest.” Id.

The claimed invention in Pfizer, Inc. v. Apotex, Inc., 480 F.3d 1348, 82 USPQ2d 1321 (Fed. Cir. 2007), was directed to the amlodipine besylate drug product, which was sold in tablet form in the United States under the trademark Norvasc ®. Amlodipine and the use of besylate anions were both known at the time of the invention. Amlodipine was known to have the same therapeutic properties as were being claimed for the amlodipine besylate, but Pfizer discovered that the besylate form had better manufacturing properties (e.g., reduced “stickiness”).

The claimed invention in Pfizer, Inc. v. Apotex, Inc., 480 F.3d 1348, 82 USPQ2d 1321 (Fed. Cir. 2007), was directed to the amlodipine besylate drug product, which was sold in tablet form in the United States under the trademark Norvasc ®. Amlodipine and the use of besylate anions were both known at the time of the invention. Amlodipine was known to have the same therapeutic properties as were being claimed for the amlodipine besylate, but Pfizer discovered that the besylate form had better manufacturing properties (e.g., reduced “stickiness”).

The claimed invention in Pfizer, Inc. v. Apotex, Inc., 480 F.3d 1348, 82 USPQ2d 1321 (Fed. Cir. 2007), was directed to the amlodipine besylate drug product, which was sold in tablet form in the United States under the trademark Norvasc ®. Amlodipine and the use of besylate anions were both known at the time of the invention. Amlodipine was known to have the same therapeutic properties as were being claimed for the amlodipine besylate, but Pfizer discovered that the besylate form had better manufacturing properties (e.g., reduced “stickiness”).

The Federal Circuit’s decision in In re Kubin, 561 F.3d 1351, 90 USPQ2d 1417 (Fed. Cir. 2009), affirmed the Office’s determination in Ex parte Kubin, 83 USPQ2d 1410 (Bd. Pat. App. & Int. 2007) that the claims in question, directed to an isolated nucleic acid molecule, would have been obvious over the prior art applied. The claim stated that the nucleic acid encoded a particular polypeptide. The encoded polypeptide was identified in the claim by its partially specified sequence, and by its ability to bind to a specified protein.

Relying on In re Deuel, 51 F.3d 1552, 34 USPQ2d 1210 (Fed. Cir. 1995), appellant argued that it was improper for the Office to use the polypeptide of the Valiante patent together with the methods described in Sambrook to reject a claim drawn to a specific nucleic acid molecule without providing a reference showing or suggesting a structurally similar nucleic acid molecule. Citing KSR, the Board stated that “when there is motivation to solve a problem and there are a finite number of identified, predictable solutions, a person of ordinary skill has good reason to pursue the known options within his or her technical grasp. If this leads to anticipated success, it is likely the product not of innovation but of ordinary skill and common sense.” KSR, 550 U.S. at 402-03, 82 USPQ2d at 1390. The Board noted that the problem facing those in the art was to isolate a specific nucleic acid, and there were a limited number of methods available to do so. The Board concluded that the skilled artisan would have had reason to try these methods with the reasonable expectation that at least one would be successful. Thus, isolating the specific nucleic acid molecule claimed was “the product not of innovation but of ordinary skill and common sense.” Id.

The Board’s reasoning was substantially adopted by the Federal Circuit. However, it is important to note that in the Kubin decision, the Federal Circuit held that “the Supreme Court in KSR unambiguously discredited” the Federal Circuit’s decision in Deuel, insofar as it “implies the obviousness inquiry cannot consider that the combination of the claim’s constituent elements was ‘obvious to try.’” Kubin, 561 F.3d at 1358, 90 USPQ2d at 1422. Instead, Kubin stated that KSR “resurrects” the Federal Circuit’s own wisdom in O’Farrell, in which “to differentiate between proper and improper applications of ‘obvious to try,’” the Federal Circuit “outlined two classes of situations where ‘obvious to try’ is erroneously equated with obviousness under § 103.” Kubin, 561 F.3d at 1359, 90 USPQ2d at 1423. These two classes of situations are: (1) when what would have been “obvious to try” would have been to vary all parameters or try each of numerous possible choices until one possibly arrived at a successful result, where the prior art gave either no indication of which parameters were critical or no direction as to which of many possible choices is likely to be successful; and (2) when what was “obvious to try” was to explore a new technology or general approach that seemed to be a promising field of experimentation, where the prior art gave only general guidance as to the particular form of the claimed invention or how to achieve it. Id. (citing In re O’Farrell, 853 F.2d 894, 903, 7 USPQ2d 1673, 1681 (Fed. Cir. 1988)).

The Board’s reasoning was substantially adopted by the Federal Circuit. However, it is important to note that in the Kubin decision, the Federal Circuit held that “the Supreme Court in KSR unambiguously discredited” the Federal Circuit’s decision in Deuel, insofar as it “implies the obviousness inquiry cannot consider that the combination of the claim’s constituent elements was ‘obvious to try.’” Kubin, 561 F.3d at 1358, 90 USPQ2d at 1422. Instead, Kubin stated that KSR “resurrects” the Federal Circuit’s own wisdom in O’Farrell, in which “to differentiate between proper and improper applications of ‘obvious to try,’” the Federal Circuit “outlined two classes of situations where ‘obvious to try’ is erroneously equated with obviousness under § 103.” Kubin, 561 F.3d at 1359, 90 USPQ2d at 1423. These two classes of situations are: (1) when what would have been “obvious to try” would have been to vary all parameters or try each of numerous possible choices until one possibly arrived at a successful result, where the prior art gave either no indication of which parameters were critical or no direction as to which of many possible choices is likely to be successful; and (2) when what was “obvious to try” was to explore a new technology or general approach that seemed to be a promising field of experimentation, where the prior art gave only general guidance as to the particular form of the claimed invention or how to achieve it. Id. (citing In re O’Farrell, 853 F.2d 894, 903, 7 USPQ2d 1673, 1681 (Fed. Cir. 1988)).

The Board’s reasoning was substantially adopted by the Federal Circuit. However, it is important to note that in the Kubin decision, the Federal Circuit held that “the Supreme Court in KSR unambiguously discredited” the Federal Circuit’s decision in Deuel, insofar as it “implies the obviousness inquiry cannot consider that the combination of the claim’s constituent elements was ‘obvious to try.’” Kubin, 561 F.3d at 1358, 90 USPQ2d at 1422. Instead, Kubin stated that KSR “resurrects” the Federal Circuit’s own wisdom in O’Farrell, in which “to differentiate between proper and improper applications of ‘obvious to try,’” the Federal Circuit “outlined two classes of situations where ‘obvious to try’ is erroneously equated with obviousness under § 103.” Kubin, 561 F.3d at 1359, 90 USPQ2d at 1423. These two classes of situations are: (1) when what would have been “obvious to try” would have been to vary all parameters or try each of numerous possible choices until one possibly arrived at a successful result, where the prior art gave either no indication of which parameters were critical or no direction as to which of many possible choices is likely to be successful; and (2) when what was “obvious to try” was to explore a new technology or general approach that seemed to be a promising field of experimentation, where the prior art gave only general guidance as to the particular form of the claimed invention or how to achieve it. Id. (citing In re O’Farrell, 853 F.2d 894, 903, 7 USPQ2d 1673, 1681 (Fed. Cir. 1988)).

The Federal Circuit held that the patent was invalid because the claimed formulation was obvious. The Federal Circuit reasoned that the prior art would have funneled the formulator toward two options. Thus, the formulator would not have been required to try all possibilities in a field unreduced by the prior art. The prior art was not vague in pointing toward a general approach or area of exploration, but rather guided the formulator precisely to the use of either a normal pill or an enteric-coated pill.

The Federal Circuit held that the patent was invalid because the claimed formulation was obvious. The Federal Circuit reasoned that the prior art would have funneled the formulator toward two options. Thus, the formulator would not have been required to try all possibilities in a field unreduced by the prior art. The prior art was not vague in pointing toward a general approach or area of exploration, but rather guided the formulator precisely to the use of either a normal pill or an enteric-coated pill.

The case of Sanofi-Synthelabo v. Apotex, Inc., 550 F.3d 1075, 89 USPQ2d 1370 (Fed. Cir. 2008), also sheds light on the obvious to try line of reasoning. The claimed compound was clopidogrel, which is the dextrorotatory isomer of methyl alpha- 5(4,5,6,7-tetrahydro(3,2-c)thienopyridyl)(2-chlorophenyl)-acetate. Clopidogrel is an anti-thrombotic compound used to treat or prevent heart attack or stroke. The racemate, or mixture of dextrorotatory and levorotatory (D- and L-) isomers of the compound, was known in the prior art. The two forms had not previously been separated, and although the mixture was known to have anti-thrombotic properties, the extent to which each of the individual isomers contributed to the observed properties of the racemate was not known and was not predictable.

The case of Sanofi-Synthelabo v. Apotex, Inc., 550 F.3d 1075, 89 USPQ2d 1370 (Fed. Cir. 2008), also sheds light on the obvious to try line of reasoning. The claimed compound was clopidogrel, which is the dextrorotatory isomer of methyl alpha- 5(4,5,6,7-tetrahydro(3,2-c)thienopyridyl)(2-chlorophenyl)-acetate. Clopidogrel is an anti-thrombotic compound used to treat or prevent heart attack or stroke. The racemate, or mixture of dextrorotatory and levorotatory (D- and L-) isomers of the compound, was known in the prior art. The two forms had not previously been separated, and although the mixture was known to have anti-thrombotic properties, the extent to which each of the individual isomers contributed to the observed properties of the racemate was not known and was not predictable.

The case of Sanofi-Synthelabo v. Apotex, Inc., 550 F.3d 1075, 89 USPQ2d 1370 (Fed. Cir. 2008), also sheds light on the obvious to try line of reasoning. The claimed compound was clopidogrel, which is the dextrorotatory isomer of methyl alpha- 5(4,5,6,7-tetrahydro(3,2-c)thienopyridyl)(2-chlorophenyl)-acetate. Clopidogrel is an anti-thrombotic compound used to treat or prevent heart attack or stroke. The racemate, or mixture of dextrorotatory and levorotatory (D- and L-) isomers of the compound, was known in the prior art. The two forms had not previously been separated, and although the mixture was known to have anti-thrombotic properties, the extent to which each of the individual isomers contributed to the observed properties of the racemate was not known and was not predictable.

Office personnel should recognize that even when only a small number of possible choices exist, the obvious to try line of reasoning is not appropriate when, upon consideration of all of the evidence, the outcome would not have been reasonably predictable and the inventor would not have had a reasonable expectation of success. In Bayer, there were art-based reasons to expect that both the normal pill and the enteric-coated pill would be therapeutically suitable, even though not all prior art studies were in complete agreement. Thus, the result obtained was not unexpected. In Sanofi, on the other hand, there was strong evidence that persons of ordinary skill in the art, prior to the separation of the isomers, would have had no reason to expect that the D-isomer would have such strong therapeutic advantages as compared with the L-isomer. In other words, the result in Sanofi was unexpected.

Office personnel should recognize that even when only a small number of possible choices exist, the obvious to try line of reasoning is not appropriate when, upon consideration of all of the evidence, the outcome would not have been reasonably predictable and the inventor would not have had a reasonable expectation of success. In Bayer, there were art-based reasons to expect that both the normal pill and the enteric-coated pill would be therapeutically suitable, even though not all prior art studies were in complete agreement. Thus, the result obtained was not unexpected. In Sanofi, on the other hand, there was strong evidence that persons of ordinary skill in the art, prior to the separation of the isomers, would have had no reason to expect that the D-isomer would have such strong therapeutic advantages as compared with the L-isomer. In other words, the result in Sanofi was unexpected.

Office personnel should recognize that even when only a small number of possible choices exist, the obvious to try line of reasoning is not appropriate when, upon consideration of all of the evidence, the outcome would not have been reasonably predictable and the inventor would not have had a reasonable expectation of success. In Bayer, there were art-based reasons to expect that both the normal pill and the enteric-coated pill would be therapeutically suitable, even though not all prior art studies were in complete agreement. Thus, the result obtained was not unexpected. In Sanofi, on the other hand, there was strong evidence that persons of ordinary skill in the art, prior to the separation of the isomers, would have had no reason to expect that the D-isomer would have such strong therapeutic advantages as compared with the L-isomer. In other words, the result in Sanofi was unexpected.

United had argued that it would have been obvious for a person of ordinary skill in the art to try a fan blade design in which the sweep angle in the outer region was reversed as compared with prior art fan blades from rearward to forward sweep, in order to reduce endwall shock. The Federal Circuit disagreed with United’s assessment that the claimed fan blade would have been obvious based on an obvious to try rationale. The Federal Circuit pointed out that in a proper obvious to try approach to obviousness, the possible options for solving a problem must have been “known and finite.” Id. at 1339, 95 USPQ2d at 1107 (citing Abbott, 544 F.3d at 1351, 89 USPQ2d at 1171). In this case, nothing in the prior art would have suggested that changing the sweep angle as Rolls-Royce had done would have addressed the issue of endwall shock. Thus, the Federal Circuit concluded that changing the sweep angle “would not have presented itself as an option at all, let alone an option that would have been obvious to try.” Id. The decision in Rolls-Royce is a reminder to Office personnel that the obvious to try rationale can properly be used to support a conclusion of obviousness only when the claimed solution would have been selected from a finite number of potential solutions known to persons of ordinary skill in the art.

The case of Perfect Web Tech., Inc. v. InfoUSA, Inc., 587 F.3d 1324, 1328-29, 92 USPQ2d 1849, 1854 (Fed. Cir. 2009), provides an example in which the Federal Circuit held that a claimed method for managing bulk email distribution was obvious on the basis of an obvious to try argument. In Perfect Web, the method required selecting the intended recipients, transmitting the emails, determining how many of the emails had been successfully received, and repeating the first three steps if a pre-determined minimum number of intended recipients had not received the email.

The Federal Circuit noted that based on “simple logic,” selecting a new list of recipients was more likely to result in the desired outcome than resending to those who had not received the email on the first attempt. There had been no evidence of any unexpected result associated with selecting a new recipient list, and no evidence that the method would not have had a reasonable likelihood of success. Thus, the Federal Circuit concluded that, as required by KSR, there were a “finite number of identified, predictable solutions,” and that the obvious to try inquiry properly led to the legal conclusion of obviousness.

The Federal Circuit pointed out that application of common sense is not really an innovation in the law of obviousness when it stated, “Common sense has long been recognized to inform the analysis of obviousness if explained with sufficient reasoning.” Perfect Web, 587 F.3d at 1328, 92 USPQ2d at 1853 (emphasis added). The Federal Circuit then provided a review of a number of precedential cases that inform the understanding of common sense, including In re Bozek, 416 F.2d 1385, 1390, 163 USPQ 545, 549 (CCPA 1969) (explaining that a patent examiner may rely on “common knowledge and common sense of the person of ordinary skill in the art without any specific hint or suggestion in a particular reference”) and In re Zurko, 258 F.3d 1379, 1383, 1385, 59 USPQ2d 1693 at 1695, 1697 (Fed. Cir. 2001) (clarifying that a factual foundation is needed in order for an examiner to invoke “good common sense” in a case in which “basic knowledge and common sense was not based on any evidence in the record”). The Federal Circuit implicitly acknowledged in Perfect Web that the kind of strict evidence-based teaching, suggestion, or motivation required in In re Lee, 277 F.3d 1338, 1344, 61 USPQ2d 1430, 1434 (Fed. Cir. 2002), is not an absolute requirement for an obviousness rejection in light of the teachings of KSR. The Federal Circuit explained that “[a]t the time [of the Lee decision], we required the PTO to identify record evidence of a teaching, suggestion, or motivation to combine references.” However, Perfect Web went on to state that even under Lee, common sense could properly be applied when analyzing evidence relevant to obviousness. Citing DyStar Textilfarben GmbH v. C.H. Patrick Co., 464 F.3d 1356, 80 USPQ2d 1641 (Fed. Cir. 2006), and In re Kahn, 441 F.3d 977, 78 USPQ2d 1329 (Fed. Cir. 2006), two cases decided shortly before the Supreme Court’s decision in KSR, the Federal Circuit noted that although “a reasoned explanation that avoids conclusory generalizations” is required to use common sense, identification of a “specific hint or suggestion in a particular reference” is not. See also B/E Aerospace, Inc. v. C&D Zodiac, Inc., 962 F.3d 1373, 1380-81, 2020 USPQ2d 10706 (Fed. Cir. 2020) (stating that “the Board’s invocation of common sense was properly accompanied by reasoned analysis and evidentiary support” to show why it would be obvious to incorporate a second recess to receive an airplane seat support). But see Arendi v. Apple, 832 F.3d 1355, 119 USPQ2d 1822 (Fed. Cir. 2016) (finding that the Board had not provided a reasoned analysis, supported by the evidence of record, for why “common sense” taught the missing process step).

The fact pattern in Dann v. Johnston, 425 U.S. 219, 189 USPQ 257 (1976) is set forth above in Example 1 in subsection D.

The claimed invention in Leapfrog Enterprises, Inc. v. Fisher-Price, Inc., 485 F.3d 1157, 82 USPQ2d 1687 (Fed. Cir. 2007) was directed to a learning device to help young children read phonetically. The claim read as follows:

The claimed invention in Leapfrog Enterprises, Inc. v. Fisher-Price, Inc., 485 F.3d 1157, 82 USPQ2d 1687 (Fed. Cir. 2007) was directed to a learning device to help young children read phonetically. The claim read as follows:

The claimed invention in KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 82 USPQ2d 1385 (2007), was an adjustable pedal assembly with a fixed pivot point and an electronic pedal-position sensor attached to the assembly support. The fixed pivot point meant that the pivot was not changed as the pedal was adjusted. The placement of the sensor on the assembly support kept the sensor fixed while the pedal was adjusted.

The claimed invention in KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 82 USPQ2d 1385 (2007), was an adjustable pedal assembly with a fixed pivot point and an electronic pedal-position sensor attached to the assembly support. The fixed pivot point meant that the pivot was not changed as the pedal was adjusted. The placement of the sensor on the assembly support kept the sensor fixed while the pedal was adjusted.

The claimed invention in KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 82 USPQ2d 1385 (2007), was an adjustable pedal assembly with a fixed pivot point and an electronic pedal-position sensor attached to the assembly support. The fixed pivot point meant that the pivot was not changed as the pedal was adjusted. The placement of the sensor on the assembly support kept the sensor fixed while the pedal was adjusted.

Conventional gas pedals operated by a mechanical link which adjusted the throttle based on the travel of the pedal from a set position. The throttle controlled the combustion process and the available power generated by the engine. Newer cars used computer controlled throttles in which a sensor detected the motion of the pedal and sent signals to the engine to adjust the throttle accordingly. At the time of the invention, the marketplace provided a strong incentive to convert mechanical pedals to electronic pedals, and the prior art taught a number of methods for doing so. The prior art (Asano) taught an adjustable pedal with a fixed pivot point with mechanical throttle control. The prior art (‘936 patent to Byler) taught an electronic pedal sensor which was placed on a pivot point in the pedal assembly and that it was preferable to detect the pedal’s position in the pedal mechanism rather than in the engine. The prior art (Smith) taught that to prevent the wires connecting the sensor to the computer from chafing and wearing out, the sensor should be put on a fixed part of the pedal assembly rather than in or on the pedal’s footpad. The prior art (Rixon) taught an adjustable pedal assembly (sensor in the footpad) with an electronic sensor for throttle control. There was no prior art electronic throttle control that was combined with a pedal assembly which kept the pivot point fixed when adjusting the pedal.

Conventional gas pedals operated by a mechanical link which adjusted the throttle based on the travel of the pedal from a set position. The throttle controlled the combustion process and the available power generated by the engine. Newer cars used computer controlled throttles in which a sensor detected the motion of the pedal and sent signals to the engine to adjust the throttle accordingly. At the time of the invention, the marketplace provided a strong incentive to convert mechanical pedals to electronic pedals, and the prior art taught a number of methods for doing so. The prior art (Asano) taught an adjustable pedal with a fixed pivot point with mechanical throttle control. The prior art (‘936 patent to Byler) taught an electronic pedal sensor which was placed on a pivot point in the pedal assembly and that it was preferable to detect the pedal’s position in the pedal mechanism rather than in the engine. The prior art (Smith) taught that to prevent the wires connecting the sensor to the computer from chafing and wearing out, the sensor should be put on a fixed part of the pedal assembly rather than in or on the pedal’s footpad. The prior art (Rixon) taught an adjustable pedal assembly (sensor in the footpad) with an electronic sensor for throttle control. There was no prior art electronic throttle control that was combined with a pedal assembly which kept the pivot point fixed when adjusting the pedal.

Conventional gas pedals operated by a mechanical link which adjusted the throttle based on the travel of the pedal from a set position. The throttle controlled the combustion process and the available power generated by the engine. Newer cars used computer controlled throttles in which a sensor detected the motion of the pedal and sent signals to the engine to adjust the throttle accordingly. At the time of the invention, the marketplace provided a strong incentive to convert mechanical pedals to electronic pedals, and the prior art taught a number of methods for doing so. The prior art (Asano) taught an adjustable pedal with a fixed pivot point with mechanical throttle control. The prior art (‘936 patent to Byler) taught an electronic pedal sensor which was placed on a pivot point in the pedal assembly and that it was preferable to detect the pedal’s position in the pedal mechanism rather than in the engine. The prior art (Smith) taught that to prevent the wires connecting the sensor to the computer from chafing and wearing out, the sensor should be put on a fixed part of the pedal assembly rather than in or on the pedal’s footpad. The prior art (Rixon) taught an adjustable pedal assembly (sensor in the footpad) with an electronic sensor for throttle control. There was no prior art electronic throttle control that was combined with a pedal assembly which kept the pivot point fixed when adjusting the pedal.

Conventional gas pedals operated by a mechanical link which adjusted the throttle based on the travel of the pedal from a set position. The throttle controlled the combustion process and the available power generated by the engine. Newer cars used computer controlled throttles in which a sensor detected the motion of the pedal and sent signals to the engine to adjust the throttle accordingly. At the time of the invention, the marketplace provided a strong incentive to convert mechanical pedals to electronic pedals, and the prior art taught a number of methods for doing so. The prior art (Asano) taught an adjustable pedal with a fixed pivot point with mechanical throttle control. The prior art (‘936 patent to Byler) taught an electronic pedal sensor which was placed on a pivot point in the pedal assembly and that it was preferable to detect the pedal’s position in the pedal mechanism rather than in the engine. The prior art (Smith) taught that to prevent the wires connecting the sensor to the computer from chafing and wearing out, the sensor should be put on a fixed part of the pedal assembly rather than in or on the pedal’s footpad. The prior art (Rixon) taught an adjustable pedal assembly (sensor in the footpad) with an electronic sensor for throttle control. There was no prior art electronic throttle control that was combined with a pedal assembly which kept the pivot point fixed when adjusting the pedal.

Conventional gas pedals operated by a mechanical link which adjusted the throttle based on the travel of the pedal from a set position. The throttle controlled the combustion process and the available power generated by the engine. Newer cars used computer controlled throttles in which a sensor detected the motion of the pedal and sent signals to the engine to adjust the throttle accordingly. At the time of the invention, the marketplace provided a strong incentive to convert mechanical pedals to electronic pedals, and the prior art taught a number of methods for doing so. The prior art (Asano) taught an adjustable pedal with a fixed pivot point with mechanical throttle control. The prior art (‘936 patent to Byler) taught an electronic pedal sensor which was placed on a pivot point in the pedal assembly and that it was preferable to detect the pedal’s position in the pedal mechanism rather than in the engine. The prior art (Smith) taught that to prevent the wires connecting the sensor to the computer from chafing and wearing out, the sensor should be put on a fixed part of the pedal assembly rather than in or on the pedal’s footpad. The prior art (Rixon) taught an adjustable pedal assembly (sensor in the footpad) with an electronic sensor for throttle control. There was no prior art electronic throttle control that was combined with a pedal assembly which kept the pivot point fixed when adjusting the pedal.

Conventional gas pedals operated by a mechanical link which adjusted the throttle based on the travel of the pedal from a set position. The throttle controlled the combustion process and the available power generated by the engine. Newer cars used computer controlled throttles in which a sensor detected the motion of the pedal and sent signals to the engine to adjust the throttle accordingly. At the time of the invention, the marketplace provided a strong incentive to convert mechanical pedals to electronic pedals, and the prior art taught a number of methods for doing so. The prior art (Asano) taught an adjustable pedal with a fixed pivot point with mechanical throttle control. The prior art (‘936 patent to Byler) taught an electronic pedal sensor which was placed on a pivot point in the pedal assembly and that it was preferable to detect the pedal’s position in the pedal mechanism rather than in the engine. The prior art (Smith) taught that to prevent the wires connecting the sensor to the computer from chafing and wearing out, the sensor should be put on a fixed part of the pedal assembly rather than in or on the pedal’s footpad. The prior art (Rixon) taught an adjustable pedal assembly (sensor in the footpad) with an electronic sensor for throttle control. There was no prior art electronic throttle control that was combined with a pedal assembly which kept the pivot point fixed when adjusting the pedal.

Conventional gas pedals operated by a mechanical link which adjusted the throttle based on the travel of the pedal from a set position. The throttle controlled the combustion process and the available power generated by the engine. Newer cars used computer controlled throttles in which a sensor detected the motion of the pedal and sent signals to the engine to adjust the throttle accordingly. At the time of the invention, the marketplace provided a strong incentive to convert mechanical pedals to electronic pedals, and the prior art taught a number of methods for doing so. The prior art (Asano) taught an adjustable pedal with a fixed pivot point with mechanical throttle control. The prior art (‘936 patent to Byler) taught an electronic pedal sensor which was placed on a pivot point in the pedal assembly and that it was preferable to detect the pedal’s position in the pedal mechanism rather than in the engine. The prior art (Smith) taught that to prevent the wires connecting the sensor to the computer from chafing and wearing out, the sensor should be put on a fixed part of the pedal assembly rather than in or on the pedal’s footpad. The prior art (Rixon) taught an adjustable pedal assembly (sensor in the footpad) with an electronic sensor for throttle control. There was no prior art electronic throttle control that was combined with a pedal assembly which kept the pivot point fixed when adjusting the pedal.

Conventional gas pedals operated by a mechanical link which adjusted the throttle based on the travel of the pedal from a set position. The throttle controlled the combustion process and the available power generated by the engine. Newer cars used computer controlled throttles in which a sensor detected the motion of the pedal and sent signals to the engine to adjust the throttle accordingly. At the time of the invention, the marketplace provided a strong incentive to convert mechanical pedals to electronic pedals, and the prior art taught a number of methods for doing so. The prior art (Asano) taught an adjustable pedal with a fixed pivot point with mechanical throttle control. The prior art (‘936 patent to Byler) taught an electronic pedal sensor which was placed on a pivot point in the pedal assembly and that it was preferable to detect the pedal’s position in the pedal mechanism rather than in the engine. The prior art (Smith) taught that to prevent the wires connecting the sensor to the computer from chafing and wearing out, the sensor should be put on a fixed part of the pedal assembly rather than in or on the pedal’s footpad. The prior art (Rixon) taught an adjustable pedal assembly (sensor in the footpad) with an electronic sensor for throttle control. There was no prior art electronic throttle control that was combined with a pedal assembly which kept the pivot point fixed when adjusting the pedal.

The Court stated that “[t]he proper question to have asked was whether a pedal designer of ordinary skill, facing the wide range of needs created by developments in the field of endeavor, would have seen a benefit to upgrading Asano with a sensor.” Id. at 424, 82 USPQ2d at 1399. The Court found that technological developments in the automotive design would have prompted a designer to upgrade Asano with an electronic sensor. The next question was where to attach the sensor. Based on the prior art, a designer would have known to place the sensor on a nonmoving part of the pedal structure and the most obvious nonmoving point on the structure from which a sensor can easily detect the pedal’s position was a pivot point. The Court concluded that it would have been obvious to upgrade Asano’s fixed pivot point adjustable pedal by replacing the mechanical assembly for throttle control with an electronic throttle control and to mount the electronic sensor on the pedal support structure.

The Court stated that “[t]he proper question to have asked was whether a pedal designer of ordinary skill, facing the wide range of needs created by developments in the field of endeavor, would have seen a benefit to upgrading Asano with a sensor.” Id. at 424, 82 USPQ2d at 1399. The Court found that technological developments in the automotive design would have prompted a designer to upgrade Asano with an electronic sensor. The next question was where to attach the sensor. Based on the prior art, a designer would have known to place the sensor on a nonmoving part of the pedal structure and the most obvious nonmoving point on the structure from which a sensor can easily detect the pedal’s position was a pivot point. The Court concluded that it would have been obvious to upgrade Asano’s fixed pivot point adjustable pedal by replacing the mechanical assembly for throttle control with an electronic throttle control and to mount the electronic sensor on the pedal support structure.

The Court stated that “[t]he proper question to have asked was whether a pedal designer of ordinary skill, facing the wide range of needs created by developments in the field of endeavor, would have seen a benefit to upgrading Asano with a sensor.” Id. at 424, 82 USPQ2d at 1399. The Court found that technological developments in the automotive design would have prompted a designer to upgrade Asano with an electronic sensor. The next question was where to attach the sensor. Based on the prior art, a designer would have known to place the sensor on a nonmoving part of the pedal structure and the most obvious nonmoving point on the structure from which a sensor can easily detect the pedal’s position was a pivot point. The Court concluded that it would have been obvious to upgrade Asano’s fixed pivot point adjustable pedal by replacing the mechanical assembly for throttle control with an electronic throttle control and to mount the electronic sensor on the pedal support structure.

The claimed invention in Ex parte Catan, 83 USPQ2d 1569 (Bd. Pat. App. & Int. 2007), was a consumer electronics device using bioauthentication to authorize sub-users of an authorized credit account to place orders over a communication network up to a pre-set maximum sub-credit limit.

The rationale to support a conclusion that the claim would have been obvious is that "a person of ordinary skill in the art would have been motivated to combine the prior art to achieve the claimed invention and whether there would have been a reasonable expectation of success in doing so." DyStar Textilfarben GmbH & Co. Deutschland KG v. C.H. Patrick Co., 464 F.3d 1356, 1360, 80 USPQ2d 1641, 1645 (Fed. Cir. 2006). If any of these findings cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.

The courts have made clear that the teaching, suggestion, or motivation test is flexible and an explicit suggestion to combine the prior art is not necessary. The motivation to combine may be implicit and may be found in the knowledge of one of ordinary skill in the art, or, in some cases, from the nature of the problem to be solved. Id. at 1366, 80 USPQ2d at 1649. “[A]n implicit motivation to combine exists not only when a suggestion may be gleaned from the prior art as a whole, but when the ‘improvement’ is technology-independent and the combination of references results in a product or process that is more desirable, for example because it is stronger, cheaper, cleaner, faster, lighter, smaller, more durable, or more efficient. Because the desire to enhance commercial opportunities by improving a product or process is universal—and even common-sensical—we have held that there exists in these situations a motivation to combine prior art references even absent any hint of suggestion in the references themselves. In such situations, the proper question is whether the ordinary artisan possesses knowledge and skills rendering him capable of combining the prior art references.” Id. at 1368, 80 USPQ2d at 1651.

The courts have made clear that the teaching, suggestion, or motivation test is flexible and an explicit suggestion to combine the prior art is not necessary. The motivation to combine may be implicit and may be found in the knowledge of one of ordinary skill in the art, or, in some cases, from the nature of the problem to be solved. Id. at 1366, 80 USPQ2d at 1649. “[A]n implicit motivation to combine exists not only when a suggestion may be gleaned from the prior art as a whole, but when the ‘improvement’ is technology-independent and the combination of references results in a product or process that is more desirable, for example because it is stronger, cheaper, cleaner, faster, lighter, smaller, more durable, or more efficient. Because the desire to enhance commercial opportunities by improving a product or process is universal—and even common-sensical—we have held that there exists in these situations a motivation to combine prior art references even absent any hint of suggestion in the references themselves. In such situations, the proper question is whether the ordinary artisan possesses knowledge and skills rendering him capable of combining the prior art references.” Id. at 1368, 80 USPQ2d at 1651.

The courts have made clear that the teaching, suggestion, or motivation test is flexible and an explicit suggestion to combine the prior art is not necessary. The motivation to combine may be implicit and may be found in the knowledge of one of ordinary skill in the art, or, in some cases, from the nature of the problem to be solved. Id. at 1366, 80 USPQ2d at 1649. “[A]n implicit motivation to combine exists not only when a suggestion may be gleaned from the prior art as a whole, but when the ‘improvement’ is technology-independent and the combination of references results in a product or process that is more desirable, for example because it is stronger, cheaper, cleaner, faster, lighter, smaller, more durable, or more efficient. Because the desire to enhance commercial opportunities by improving a product or process is universal—and even common-sensical—we have held that there exists in these situations a motivation to combine prior art references even absent any hint of suggestion in the references themselves. In such situations, the proper question is whether the ordinary artisan possesses knowledge and skills rendering him capable of combining the prior art references.” Id. at 1368, 80 USPQ2d at 1651.

The Federal Circuit’s directive in Ball Aerosol was addressed to a lower court, but it applies to Office personnel as well. When setting forth a rejection, Office personnel are to continue to make appropriate findings of fact as explained in MPEP § 2141 and § 2143, and must provide a reasoned explanation as to why the invention as claimed would have been obvious to a person of ordinary skill in the art at the relevant time. This requirement for explanation remains even in situations in which Office personnel may properly rely on common sense or ordinary ingenuity. In re Van Os, 844 F.3d 1359, 1361, 121 USPQ2d 1209, 1211 (Fed. Cir. 2017) (“Absent some articulated rationale, a finding that a combination of prior art would have been ‘common sense’ or ‘intuitive’ is no different than merely stating the combination ‘would have been obvious.’”).

The Federal Circuit’s directive in Ball Aerosol was addressed to a lower court, but it applies to Office personnel as well. When setting forth a rejection, Office personnel are to continue to make appropriate findings of fact as explained in MPEP § 2141 and § 2143, and must provide a reasoned explanation as to why the invention as claimed would have been obvious to a person of ordinary skill in the art at the relevant time. This requirement for explanation remains even in situations in which Office personnel may properly rely on common sense or ordinary ingenuity. In re Van Os, 844 F.3d 1359, 1361, 121 USPQ2d 1209, 1211 (Fed. Cir. 2017) (“Absent some articulated rationale, a finding that a combination of prior art would have been ‘common sense’ or ‘intuitive’ is no different than merely stating the combination ‘would have been obvious.’”).

The rationale to support a conclusion that the claim would have been obvious is that all the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination yielded nothing more than predictable results to one of ordinary skill in the art. KSR, 550 U.S. at 416, 82 USPQ2d at 1395; B/E Aerospace, Inc. v. C&D Zodiac, Inc., 962 F.3d 1373, 1379, 2020 USPQ2d 10706 (Fed. Cir. 2020); Sakraida v. AG Pro, Inc., 425 U.S. 273, 282, 189 USPQ 449, 453 (1976); Anderson’s-Black Rock, Inc. v. Pavement Salvage Co., 396 U.S. 57, 62-63, 163 USPQ 673, 675 (1969); Great Atl. & P. Tea Co. v. Supermarket Equip. Corp., 340 U.S. 147, 152, 87 USPQ 303, 306 (1950). “[I]t can be important to identify a reason that would have prompted a person of ordinary skill in the relevant field to combine the elements in the way the claimed new invention does.” KSR, 550 U.S. at 418, 82 USPQ2d at 1396. If any of these findings cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.

The claimed invention in Anderson’s-Black Rock, Inc. v. Pavement Salvage Co., 396 U.S. 57, 163 USPQ 673 (1969) was a paving machine which combined several well-known elements onto a single chassis. Standard prior art paving machines typically combined equipment for spreading and shaping asphalt onto a single chassis. The patent claim included the well-known element of a radiant-heat burner attached to the side of the paver for the purpose of preventing cold joints during continuous strip paving. The prior art used radiant heat for softening the asphalt to make patches, but did not use radiant heat burners to achieve continuous strip paving. All of the component parts were known in the prior art. The only difference was the combination of the “old elements” into a single device by mounting them on a single chassis. The Court found that the operation of the heater was in no way dependent on the operation of the other equipment, and that a separate heater could also be used in conjunction with a standard paving machine to achieve the same results. The Court concluded that “[t]he convenience of putting the burner together with the other elements in one machine, though perhaps a matter of great convenience, did not produce a ‘new’ or ‘different function’” and that to those skilled in the art the use of the old elements in combination would have been obvious. Id. at 60, 163 USPQ at 674.

The case of In re Omeprazole Patent Litigation, 536 F.3d 1361, 87 USPQ2d 1865 (Fed. Cir. 2008), is one in which the claims in question were found to be nonobvious in the context of an argument to combine prior art elements. The invention involved applying enteric coatings to a drug in pill form for the purpose of ensuring that the drug did not disintegrate before reaching its intended site of action. The drug at issue was omeprazole, the generic name for gastric acid inhibitor marketed as Prilosec ®. The claimed formulation included two layers of coatings over the active ingredient.

Sundance, Inc. v. DeMonte Fabricating Ltd., 550 F.3d 1356, 89 USPQ2d 1535 (Fed. Cir. 2008), involved a segmented and mechanized cover for trucks, swimming pools, or other structures. The claim was found to be obvious over the prior art applied.

In the case of Ecolab, Inc. v. FMC Corp., 569 F.3d 1335, 91 USPQ2d 1225 (Fed. Cir. 2009), an “apparent reason to combine” in conjunction with the technical ability to optimize led to the conclusion that the claimed invention would have been obvious.

In the case of Wyers v. Master Lock Co., 616 F.3d 1231, 95 USPQ2d 1525 (Fed. Cir. 2010), the Federal Circuit held that the claimed barbell-shaped hitch pin locks used to secure trailers to vehicles were obvious.

Office personnel should note that although the Federal Circuit invoked the idea of common sense in support of a conclusion of obviousness, it did not end its explanation there. Rather, the court explained why a person of ordinary skill in the art at the time of the invention, in view of the facts relevant to the case, would have found the claimed inventions to have been obvious. The key to supporting any rejection under 35 U.S.C. 103 is the clear articulation of the reason(s) why the claimed invention would have been obvious. The Supreme Court in KSR noted that the analysis supporting a rejection under 35 U.S.C. 103 should be made explicit. The Court quoting In re Kahn, 441 F.3d 977, 988, 78 USPQ2d 1329, 1336 (Fed. Cir. 2006), stated that “[R]ejections on obviousness cannot be sustained by mere conclusory statements; instead, there must be some articulated reasoning with some rational underpinning to support the legal conclusion of obviousness.” See MPEP § 2141, subsection III. Office personnel should continue to provide a reasoned explanation for every obviousness rejection.

Office personnel should note that although the Federal Circuit invoked the idea of common sense in support of a conclusion of obviousness, it did not end its explanation there. Rather, the court explained why a person of ordinary skill in the art at the time of the invention, in view of the facts relevant to the case, would have found the claimed inventions to have been obvious. The key to supporting any rejection under 35 U.S.C. 103 is the clear articulation of the reason(s) why the claimed invention would have been obvious. The Supreme Court in KSR noted that the analysis supporting a rejection under 35 U.S.C. 103 should be made explicit. The Court quoting In re Kahn, 441 F.3d 977, 988, 78 USPQ2d 1329, 1336 (Fed. Cir. 2006), stated that “[R]ejections on obviousness cannot be sustained by mere conclusory statements; instead, there must be some articulated reasoning with some rational underpinning to support the legal conclusion of obviousness.” See MPEP § 2141, subsection III. Office personnel should continue to provide a reasoned explanation for every obviousness rejection.

Office personnel should note that although the Federal Circuit invoked the idea of common sense in support of a conclusion of obviousness, it did not end its explanation there. Rather, the court explained why a person of ordinary skill in the art at the time of the invention, in view of the facts relevant to the case, would have found the claimed inventions to have been obvious. The key to supporting any rejection under 35 U.S.C. 103 is the clear articulation of the reason(s) why the claimed invention would have been obvious. The Supreme Court in KSR noted that the analysis supporting a rejection under 35 U.S.C. 103 should be made explicit. The Court quoting In re Kahn, 441 F.3d 977, 988, 78 USPQ2d 1329, 1336 (Fed. Cir. 2006), stated that “[R]ejections on obviousness cannot be sustained by mere conclusory statements; instead, there must be some articulated reasoning with some rational underpinning to support the legal conclusion of obviousness.” See MPEP § 2141, subsection III. Office personnel should continue to provide a reasoned explanation for every obviousness rejection.

The rationale to support a conclusion that the claim would have been obvious is that the substitution of one known element for another yields predictable results to one of ordinary skill in the art. If any of these findings cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.

The claimed invention in In re ICON Health & Fitness, Inc., 496 F.3d 1374, 83 USPQ2d 1746 (Fed. Cir. 2007), was directed to a treadmill with a folding tread base that swivels into an upright storage position, including a gas spring connected between the tread base and the upright structure to assist in stably retaining the tread base in the storage position. On reexamination, the examiner rejected the claims as obvious based on a combination of references including an advertisement (Damark) for a folding treadmill demonstrating all of the claim elements other than the gas spring, and a patent (Teague) with a gas spring. Teague was directed to a bed that folds into a cabinet using a novel dual-action spring that reverses force as the mechanism passes a neutral position, rather than a single-action spring that would provide a force pushing the bed closed at all times. The dual-action spring reduced the force required to open the bed from the closed position, while reducing the force required to lift the bed from the open position.

In Aventis Pharma Deutschland v. Lupin Ltd., 499 F.3d 1293, 84 USPQ2d 1197 (Fed. Cir. 2007), the claims were drawn to the 5(S) stereoisomer of the blood pressure drug ramipril in stereochemically pure form, and to compositions and methods requiring 5(S) ramipril. The 5(S) stereoisomer is one in which all five stereocenters in the ramipril molecule are in the S rather than the R configuration. A mixture of various stereoisomers including 5(S) ramipril had been taught by the prior art. The question before the court was whether the purified single stereoisomer would have been obvious over the known mixture of stereoisomers.

It should be noted that the lead compound cases do not stand for the proposition that identification of a single lead compound is necessary in every obviousness rejection of a chemical compound. For example, one might envision a suggestion in the prior art to formulate a compound having certain structurally defined moieties, or moieties with certain properties. If a person of ordinary skill would have known how to synthesize such a compound, and the structural and/or functional result could reasonably have been predicted, then a prima facie case of obviousness of the claimed chemical compound might exist even without identification of a particular lead compound. As a second example, it could be possible to view a claimed compound as consisting of two known compounds attached via a chemical linker. The claimed compound might properly be found to have been obvious if there would have been a reason to link the two, if one of ordinary skill would have known how to do so, and if the resulting compound would have been the predictable result of the linkage procedure. Thus, Office personnel should recognize that in certain situations, it may be proper to reject a claimed chemical compound as obvious even without identifying a single lead compound.

The rationale to support a conclusion that the claim would have been obvious is that a method of enhancing a particular class of devices (methods, or products) has been made part of the ordinary capabilities of one skilled in the art based upon the teaching of such improvement in other situations. One of ordinary skill in the art would have been capable of applying this known method of enhancement to a “base” device (method, or product) in the prior art and the results would have been predictable to one of ordinary skill in the art. “It's enough … to show that there was a known problem … in the art, that [another reference] … helped address that issue, and that combining the teachings of [the two references] wasn't beyond the skill of an ordinary artisan. Nothing more is required to show a motivation to combine under KSR. ” See Intel Corp. v. PACT XPP Schweiz AG, 61 F.4th 1373, 1380-81, 2023 USPQ2d 297 (Fed. Cir. 2023) (finding that both prior art references “address the same problem and that [the secondary reference’s] cache was a known way to address that problem is precisely the reason that there's a motivation to combine under KSR and our precedent.”).

The Supreme Court in KSR noted that if the actual application of the technique would have been beyond the skill of one of ordinary skill in the art, then using the technique would not have been obvious. KSR, 550 U.S. at 417, 82 USPQ2d at 1396. If any of these findings cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.

The Supreme Court in KSR noted that if the actual application of the technique would have been beyond the skill of one of ordinary skill in the art, then using the technique would not have been obvious. KSR, 550 U.S. at 417, 82 USPQ2d at 1396. If any of these findings cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.

The nature of the problem to be solved may lead inventors to look at references relating to possible solutions to that problem. Id. at 1277, 69 USPQ2d at 1691. Therefore, it would have been obvious to use a metal bracket (as shown in Gregory) with the screw anchor (as shown in Fuller) to underpin unstable foundations.

The rationale to support a conclusion that the claim would have been obvious is that a particular known technique was recognized as part of the ordinary capabilities of one skilled in the art. One of ordinary skill in the art would have been capable of applying this known technique to a known device (method, or product) that was ready for improvement and the results would have been predictable to one of ordinary skill in the art. If any of these findings cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.

The rationale to support a conclusion that the claim would have been obvious is that a particular known technique was recognized as part of the ordinary capabilities of one skilled in the art. One of ordinary skill in the art would have been capable of applying this known technique to a known device (method, or product) that was ready for improvement and the results would have been predictable to one of ordinary skill in the art. If any of these findings cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.

The rationale to support a conclusion that the claim would have been obvious is that “a person of ordinary skill has good reason to pursue the known options within his or her technical grasp. If this leads to the anticipated success, it is likely that product [was] not of innovation but of ordinary skill and common sense. In that instance the fact that a combination was obvious to try might show that it was obvious under § 103.” KSR, 550 U.S. at 421, 82 USPQ2d at 1397. If any of these findings cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.

The rationale to support a conclusion that the claim would have been obvious is that “a person of ordinary skill has good reason to pursue the known options within his or her technical grasp. If this leads to the anticipated success, it is likely that product [was] not of innovation but of ordinary skill and common sense. In that instance the fact that a combination was obvious to try might show that it was obvious under § 103.” KSR, 550 U.S. at 421, 82 USPQ2d at 1397. If any of these findings cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.

The Federal Circuit’s decision in In re Kubin, 561 F.3d 1351, 90 USPQ2d 1417 (Fed. Cir. 2009), affirmed the Office’s determination in Ex parte Kubin, 83 USPQ2d 1410 (Bd. Pat. App. & Int. 2007) that the claims in question, directed to an isolated nucleic acid molecule, would have been obvious over the prior art applied. The claim stated that the nucleic acid encoded a particular polypeptide. The encoded polypeptide was identified in the claim by its partially specified sequence, and by its ability to bind to a specified protein.

The Federal Circuit held that the patent was invalid because the claimed formulation was obvious. The Federal Circuit reasoned that the prior art would have funneled the formulator toward two options. Thus, the formulator would not have been required to try all possibilities in a field unreduced by the prior art. The prior art was not vague in pointing toward a general approach or area of exploration, but rather guided the formulator precisely to the use of either a normal pill or an enteric-coated pill.

United had argued that it would have been obvious for a person of ordinary skill in the art to try a fan blade design in which the sweep angle in the outer region was reversed as compared with prior art fan blades from rearward to forward sweep, in order to reduce endwall shock. The Federal Circuit disagreed with United’s assessment that the claimed fan blade would have been obvious based on an obvious to try rationale. The Federal Circuit pointed out that in a proper obvious to try approach to obviousness, the possible options for solving a problem must have been “known and finite.” Id. at 1339, 95 USPQ2d at 1107 (citing Abbott, 544 F.3d at 1351, 89 USPQ2d at 1171). In this case, nothing in the prior art would have suggested that changing the sweep angle as Rolls-Royce had done would have addressed the issue of endwall shock. Thus, the Federal Circuit concluded that changing the sweep angle “would not have presented itself as an option at all, let alone an option that would have been obvious to try.” Id. The decision in Rolls-Royce is a reminder to Office personnel that the obvious to try rationale can properly be used to support a conclusion of obviousness only when the claimed solution would have been selected from a finite number of potential solutions known to persons of ordinary skill in the art.

The rationale to support a conclusion that the claimed invention would have been obvious is that design incentives or other market forces could have prompted one of ordinary skill in the art to vary the prior art in a predictable manner to result in the claimed invention. If any of these findings cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.

The rationale to support a conclusion that the claimed invention would have been obvious is that design incentives or other market forces could have prompted one of ordinary skill in the art to vary the prior art in a predictable manner to result in the claimed invention. If any of these findings cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.

The Court stated that “[t]he proper question to have asked was whether a pedal designer of ordinary skill, facing the wide range of needs created by developments in the field of endeavor, would have seen a benefit to upgrading Asano with a sensor.” Id. at 424, 82 USPQ2d at 1399. The Court found that technological developments in the automotive design would have prompted a designer to upgrade Asano with an electronic sensor. The next question was where to attach the sensor. Based on the prior art, a designer would have known to place the sensor on a nonmoving part of the pedal structure and the most obvious nonmoving point on the structure from which a sensor can easily detect the pedal’s position was a pivot point. The Court concluded that it would have been obvious to upgrade Asano’s fixed pivot point adjustable pedal by replacing the mechanical assembly for throttle control with an electronic throttle control and to mount the electronic sensor on the pedal support structure.

The Court stated that “[t]he proper question to have asked was whether a pedal designer of ordinary skill, facing the wide range of needs created by developments in the field of endeavor, would have seen a benefit to upgrading Asano with a sensor.” Id. at 424, 82 USPQ2d at 1399. The Court found that technological developments in the automotive design would have prompted a designer to upgrade Asano with an electronic sensor. The next question was where to attach the sensor. Based on the prior art, a designer would have known to place the sensor on a nonmoving part of the pedal structure and the most obvious nonmoving point on the structure from which a sensor can easily detect the pedal’s position was a pivot point. The Court concluded that it would have been obvious to upgrade Asano’s fixed pivot point adjustable pedal by replacing the mechanical assembly for throttle control with an electronic throttle control and to mount the electronic sensor on the pedal support structure.

The rationale to support a conclusion that the claim would have been obvious is that "a person of ordinary skill in the art would have been motivated to combine the prior art to achieve the claimed invention and whether there would have been a reasonable expectation of success in doing so." DyStar Textilfarben GmbH & Co. Deutschland KG v. C.H. Patrick Co., 464 F.3d 1356, 1360, 80 USPQ2d 1641, 1645 (Fed. Cir. 2006). If any of these findings cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.

The rationale to support a conclusion that the claim would have been obvious is that "a person of ordinary skill in the art would have been motivated to combine the prior art to achieve the claimed invention and whether there would have been a reasonable expectation of success in doing so." DyStar Textilfarben GmbH & Co. Deutschland KG v. C.H. Patrick Co., 464 F.3d 1356, 1360, 80 USPQ2d 1641, 1645 (Fed. Cir. 2006). If any of these findings cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.

Examples of rationales that may support a conclusion of obviousness include:

• (A) Combining prior art elements according to known methods to yield predictable results;
• (B) Simple substitution of one known element for another to obtain predictable results;
• (C) Use of known technique to improve similar devices (methods, or products) in the same way;
• (D) Applying a known technique to a known device (method, or product) ready for improvement to yield predictable results;
• (E) “Obvious to try” – choosing from a finite number of identified, predictable solutions, with a reasonable expectation of success;
• (F) Known work in one field of endeavor may prompt variations of it for use in either the same field or a different one based on design incentives or other market forces if the variations are predictable to one of ordinary skill in the art;
• (G) Some teaching, suggestion, or motivation in the prior art that would have led one of ordinary skill to modify the prior art reference or to combine prior art reference teachings to arrive at the claimed invention.

Note that the list of rationales provided is not intended to be an all-inclusive list. Other rationales to support a conclusion of obviousness may be relied upon by Office personnel. Any rationale employed must provide a link between the factual findings and the legal conclusion of obviousness.

Note that the list of rationales provided is not intended to be an all-inclusive list. Other rationales to support a conclusion of obviousness may be relied upon by Office personnel. Any rationale employed must provide a link between the factual findings and the legal conclusion of obviousness.

It is important for Office personnel to recognize that when they do choose to formulate an obviousness rejection using one of the rationales suggested by the Supreme Court in KSR and discussed herein, they are to adhere to the guidance provided regarding the necessary factual findings. It remains Office policy that appropriate factual findings are required in order to apply the enumerated rationales properly.

The subsections below include discussions of each rationale along with examples illustrating how the cited rationales may be used to support a finding of obviousness. Some examples use the facts of pre- KSR cases to show how the rationales suggested by the Court in KSR may be used to support a finding of obviousness. The cases cited (from which the facts were derived) may not necessarily stand for the proposition that the particular rationale is the basis for the court’s holding of obviousness, but they do illustrate consistency of past decisions with the lines of reasoning laid out in KSR. Other examples are post- KSR decisions that show how the Federal Circuit has applied the principles of KSR. Cases are included that illustrate findings of obviousness as well as nonobviousness. Note that, in some instances, a single case is used in different subsections to illustrate the use of more than one rationale to support a finding of obviousness. It will often be the case that, once the Graham inquiries have been satisfactorily resolved, a conclusion of obviousness may be supported by more than one line of reasoning.

The subsections below include discussions of each rationale along with examples illustrating how the cited rationales may be used to support a finding of obviousness. Some examples use the facts of pre- KSR cases to show how the rationales suggested by the Court in KSR may be used to support a finding of obviousness. The cases cited (from which the facts were derived) may not necessarily stand for the proposition that the particular rationale is the basis for the court’s holding of obviousness, but they do illustrate consistency of past decisions with the lines of reasoning laid out in KSR. Other examples are post- KSR decisions that show how the Federal Circuit has applied the principles of KSR. Cases are included that illustrate findings of obviousness as well as nonobviousness. Note that, in some instances, a single case is used in different subsections to illustrate the use of more than one rationale to support a finding of obviousness. It will often be the case that, once the Graham inquiries have been satisfactorily resolved, a conclusion of obviousness may be supported by more than one line of reasoning.

The subsections below include discussions of each rationale along with examples illustrating how the cited rationales may be used to support a finding of obviousness. Some examples use the facts of pre- KSR cases to show how the rationales suggested by the Court in KSR may be used to support a finding of obviousness. The cases cited (from which the facts were derived) may not necessarily stand for the proposition that the particular rationale is the basis for the court’s holding of obviousness, but they do illustrate consistency of past decisions with the lines of reasoning laid out in KSR. Other examples are post- KSR decisions that show how the Federal Circuit has applied the principles of KSR. Cases are included that illustrate findings of obviousness as well as nonobviousness. Note that, in some instances, a single case is used in different subsections to illustrate the use of more than one rationale to support a finding of obviousness. It will often be the case that, once the Graham inquiries have been satisfactorily resolved, a conclusion of obviousness may be supported by more than one line of reasoning.

The subsections below include discussions of each rationale along with examples illustrating how the cited rationales may be used to support a finding of obviousness. Some examples use the facts of pre- KSR cases to show how the rationales suggested by the Court in KSR may be used to support a finding of obviousness. The cases cited (from which the facts were derived) may not necessarily stand for the proposition that the particular rationale is the basis for the court’s holding of obviousness, but they do illustrate consistency of past decisions with the lines of reasoning laid out in KSR. Other examples are post- KSR decisions that show how the Federal Circuit has applied the principles of KSR. Cases are included that illustrate findings of obviousness as well as nonobviousness. Note that, in some instances, a single case is used in different subsections to illustrate the use of more than one rationale to support a finding of obviousness. It will often be the case that, once the Graham inquiries have been satisfactorily resolved, a conclusion of obviousness may be supported by more than one line of reasoning.

The subsections below include discussions of each rationale along with examples illustrating how the cited rationales may be used to support a finding of obviousness. Some examples use the facts of pre- KSR cases to show how the rationales suggested by the Court in KSR may be used to support a finding of obviousness. The cases cited (from which the facts were derived) may not necessarily stand for the proposition that the particular rationale is the basis for the court’s holding of obviousness, but they do illustrate consistency of past decisions with the lines of reasoning laid out in KSR. Other examples are post- KSR decisions that show how the Federal Circuit has applied the principles of KSR. Cases are included that illustrate findings of obviousness as well as nonobviousness. Note that, in some instances, a single case is used in different subsections to illustrate the use of more than one rationale to support a finding of obviousness. It will often be the case that, once the Graham inquiries have been satisfactorily resolved, a conclusion of obviousness may be supported by more than one line of reasoning.

To reject a claim based on this rationale, Office personnel must resolve the Graham factual inquiries. Then, Office personnel must articulate the following:
…
(4) whatever additional findings based on the Graham factual inquiries may be necessary, in view of the facts of the case under consideration, to explain a conclusion of obviousness.

Office personnel should note that in this case the modification of the prior art that had been presented as an argument for obviousness was an extra process step that added an additional component to a known, successfully marketed formulation. The proposed modification thus amounted to extra work and greater expense for no apparent reason. This is not the same as combining known prior art elements A and B when each would have been expected to contribute its own known properties to the final product. In the Omeprazole case, in view of the expectations of those of ordinary skill in the art, adding the subcoating would not have been expected to confer any particular desirable property on the final product. Rather, the final product obtained according to the proposed modifications would merely have been expected to have the same functional properties as the prior art product.

The Federal Circuit’s discussion in Crocs serves as a reminder to Office personnel that merely pointing to the presence of all claim elements in the prior art is not a complete statement of a rejection for obviousness. In accordance with MPEP § 2143, subsection I.A.(3), a proper rejection based on the rationale that the claimed invention is a combination of prior art elements also includes a finding that results flowing from the combination would have been predictable to a person of ordinary skill in the art. MPEP § 2143, subsection I.A.(3). If results would not have been predictable, Office personnel should not enter an obviousness rejection using the combination of prior art elements rationale, and should withdraw such a rejection if it has been made.

The Federal Circuit’s discussion in Crocs serves as a reminder to Office personnel that merely pointing to the presence of all claim elements in the prior art is not a complete statement of a rejection for obviousness. In accordance with MPEP § 2143, subsection I.A.(3), a proper rejection based on the rationale that the claimed invention is a combination of prior art elements also includes a finding that results flowing from the combination would have been predictable to a person of ordinary skill in the art. MPEP § 2143, subsection I.A.(3). If results would not have been predictable, Office personnel should not enter an obviousness rejection using the combination of prior art elements rationale, and should withdraw such a rejection if it has been made.

When considering the question of obviousness, Office personnel should keep in mind the capabilities of a person of ordinary skill. In Ecolab, the Federal Circuit stated:

Office personnel should note that although the Federal Circuit invoked the idea of common sense in support of a conclusion of obviousness, it did not end its explanation there. Rather, the court explained why a person of ordinary skill in the art at the time of the invention, in view of the facts relevant to the case, would have found the claimed inventions to have been obvious. The key to supporting any rejection under 35 U.S.C. 103 is the clear articulation of the reason(s) why the claimed invention would have been obvious. The Supreme Court in KSR noted that the analysis supporting a rejection under 35 U.S.C. 103 should be made explicit. The Court quoting In re Kahn, 441 F.3d 977, 988, 78 USPQ2d 1329, 1336 (Fed. Cir. 2006), stated that “[R]ejections on obviousness cannot be sustained by mere conclusory statements; instead, there must be some articulated reasoning with some rational underpinning to support the legal conclusion of obviousness.” See MPEP § 2141, subsection III. Office personnel should continue to provide a reasoned explanation for every obviousness rejection.

Office personnel should note that although the Federal Circuit invoked the idea of common sense in support of a conclusion of obviousness, it did not end its explanation there. Rather, the court explained why a person of ordinary skill in the art at the time of the invention, in view of the facts relevant to the case, would have found the claimed inventions to have been obvious. The key to supporting any rejection under 35 U.S.C. 103 is the clear articulation of the reason(s) why the claimed invention would have been obvious. The Supreme Court in KSR noted that the analysis supporting a rejection under 35 U.S.C. 103 should be made explicit. The Court quoting In re Kahn, 441 F.3d 977, 988, 78 USPQ2d 1329, 1336 (Fed. Cir. 2006), stated that “[R]ejections on obviousness cannot be sustained by mere conclusory statements; instead, there must be some articulated reasoning with some rational underpinning to support the legal conclusion of obviousness.” See MPEP § 2141, subsection III. Office personnel should continue to provide a reasoned explanation for every obviousness rejection.

Office personnel should note that although the Federal Circuit invoked the idea of common sense in support of a conclusion of obviousness, it did not end its explanation there. Rather, the court explained why a person of ordinary skill in the art at the time of the invention, in view of the facts relevant to the case, would have found the claimed inventions to have been obvious. The key to supporting any rejection under 35 U.S.C. 103 is the clear articulation of the reason(s) why the claimed invention would have been obvious. The Supreme Court in KSR noted that the analysis supporting a rejection under 35 U.S.C. 103 should be made explicit. The Court quoting In re Kahn, 441 F.3d 977, 988, 78 USPQ2d 1329, 1336 (Fed. Cir. 2006), stated that “[R]ejections on obviousness cannot be sustained by mere conclusory statements; instead, there must be some articulated reasoning with some rational underpinning to support the legal conclusion of obviousness.” See MPEP § 2141, subsection III. Office personnel should continue to provide a reasoned explanation for every obviousness rejection.

To reject a claim based on this rationale, Office personnel must resolve the Graham factual inquiries. Then, Office personnel must articulate the following:
…
(4) whatever additional findings based on the Graham factual inquiries may be necessary, in view of the facts of the case under consideration, to explain a conclusion of obviousness.

The Federal Circuit in Eisai makes it clear that from the perspective of the law of obviousness, any known compound might possibly serve as a lead compound: “Obviousness based on structural similarity thus can be proved by identification of some motivation that would have led one of ordinary skill in the art to select and then modify a known compound (i.e. a lead compound) in a particular way to achieve the claimed compound.” Eisai, 533 F.3d at 1357, 87 USPQ2d at 1455. Thus, Office personnel should recognize that a proper obviousness rejection of a claimed compound that is useful as a drug might be made beginning with an inactive compound, if, for example, the reasons for modifying a prior art compound to arrive at the claimed compound have nothing to do with pharmaceutical activity. The inactive compound would not be considered to be a lead compound by pharmaceutical chemists, but could potentially be used as such when considering obviousness. Office personnel might also base an obviousness rejection on a known compound that pharmaceutical chemists would not select as a lead compound due to expense, handling issues, or other business considerations. However, there must be some reason for starting with that particular lead compound other than the mere fact that the “lead compound” exists. See Altana Pharma AG v. Teva Pharm. USA, Inc., 566 F.3d 999, 1007, 91 USPQ2d 1018, 1024 (Fed. Cir. 2009) (holding that there must be some reason “to select and modify a known compound”); Ortho-McNeil Pharm., Inc. v. Mylan Labs, Inc., 520 F.3d 1358, 1364, 86 USPQ2d 1196, 1201 (Fed. Cir. 2008).

The Federal Circuit in Eisai makes it clear that from the perspective of the law of obviousness, any known compound might possibly serve as a lead compound: “Obviousness based on structural similarity thus can be proved by identification of some motivation that would have led one of ordinary skill in the art to select and then modify a known compound (i.e. a lead compound) in a particular way to achieve the claimed compound.” Eisai, 533 F.3d at 1357, 87 USPQ2d at 1455. Thus, Office personnel should recognize that a proper obviousness rejection of a claimed compound that is useful as a drug might be made beginning with an inactive compound, if, for example, the reasons for modifying a prior art compound to arrive at the claimed compound have nothing to do with pharmaceutical activity. The inactive compound would not be considered to be a lead compound by pharmaceutical chemists, but could potentially be used as such when considering obviousness. Office personnel might also base an obviousness rejection on a known compound that pharmaceutical chemists would not select as a lead compound due to expense, handling issues, or other business considerations. However, there must be some reason for starting with that particular lead compound other than the mere fact that the “lead compound” exists. See Altana Pharma AG v. Teva Pharm. USA, Inc., 566 F.3d 999, 1007, 91 USPQ2d 1018, 1024 (Fed. Cir. 2009) (holding that there must be some reason “to select and modify a known compound”); Ortho-McNeil Pharm., Inc. v. Mylan Labs, Inc., 520 F.3d 1358, 1364, 86 USPQ2d 1196, 1201 (Fed. Cir. 2008).

The Federal Circuit in Eisai makes it clear that from the perspective of the law of obviousness, any known compound might possibly serve as a lead compound: “Obviousness based on structural similarity thus can be proved by identification of some motivation that would have led one of ordinary skill in the art to select and then modify a known compound (i.e. a lead compound) in a particular way to achieve the claimed compound.” Eisai, 533 F.3d at 1357, 87 USPQ2d at 1455. Thus, Office personnel should recognize that a proper obviousness rejection of a claimed compound that is useful as a drug might be made beginning with an inactive compound, if, for example, the reasons for modifying a prior art compound to arrive at the claimed compound have nothing to do with pharmaceutical activity. The inactive compound would not be considered to be a lead compound by pharmaceutical chemists, but could potentially be used as such when considering obviousness. Office personnel might also base an obviousness rejection on a known compound that pharmaceutical chemists would not select as a lead compound due to expense, handling issues, or other business considerations. However, there must be some reason for starting with that particular lead compound other than the mere fact that the “lead compound” exists. See Altana Pharma AG v. Teva Pharm. USA, Inc., 566 F.3d 999, 1007, 91 USPQ2d 1018, 1024 (Fed. Cir. 2009) (holding that there must be some reason “to select and modify a known compound”); Ortho-McNeil Pharm., Inc. v. Mylan Labs, Inc., 520 F.3d 1358, 1364, 86 USPQ2d 1196, 1201 (Fed. Cir. 2008).

The Federal Circuit in Eisai makes it clear that from the perspective of the law of obviousness, any known compound might possibly serve as a lead compound: “Obviousness based on structural similarity thus can be proved by identification of some motivation that would have led one of ordinary skill in the art to select and then modify a known compound (i.e. a lead compound) in a particular way to achieve the claimed compound.” Eisai, 533 F.3d at 1357, 87 USPQ2d at 1455. Thus, Office personnel should recognize that a proper obviousness rejection of a claimed compound that is useful as a drug might be made beginning with an inactive compound, if, for example, the reasons for modifying a prior art compound to arrive at the claimed compound have nothing to do with pharmaceutical activity. The inactive compound would not be considered to be a lead compound by pharmaceutical chemists, but could potentially be used as such when considering obviousness. Office personnel might also base an obviousness rejection on a known compound that pharmaceutical chemists would not select as a lead compound due to expense, handling issues, or other business considerations. However, there must be some reason for starting with that particular lead compound other than the mere fact that the “lead compound” exists. See Altana Pharma AG v. Teva Pharm. USA, Inc., 566 F.3d 999, 1007, 91 USPQ2d 1018, 1024 (Fed. Cir. 2009) (holding that there must be some reason “to select and modify a known compound”); Ortho-McNeil Pharm., Inc. v. Mylan Labs, Inc., 520 F.3d 1358, 1364, 86 USPQ2d 1196, 1201 (Fed. Cir. 2008).

The Federal Circuit noted in dicta that even if a prima facie case of obviousness had been established, sufficient evidence of unexpected results was introduced to rebut such a showing. At trial, the witnesses consistently testified that the properties of risedronate were not expected, offering evidence that researchers did not predict either the potency or the low dose at which the compound was effective. Tests comparing risedronate to a compound in the prior art reference showed that risedronate outperformed the other compound by a substantial margin, could be administered in a greater amount without an observable toxic effect, and was not lethal at the same levels as the other compound. The weight of the evidence and the credibility of the witnesses were sufficient to show unexpected results that would have rebutted an obviousness determination. Thus, nonobviousness can be shown when a claimed invention is shown to have unexpectedly superior properties when compared to the prior art.

It should be noted that the lead compound cases do not stand for the proposition that identification of a single lead compound is necessary in every obviousness rejection of a chemical compound. For example, one might envision a suggestion in the prior art to formulate a compound having certain structurally defined moieties, or moieties with certain properties. If a person of ordinary skill would have known how to synthesize such a compound, and the structural and/or functional result could reasonably have been predicted, then a prima facie case of obviousness of the claimed chemical compound might exist even without identification of a particular lead compound. As a second example, it could be possible to view a claimed compound as consisting of two known compounds attached via a chemical linker. The claimed compound might properly be found to have been obvious if there would have been a reason to link the two, if one of ordinary skill would have known how to do so, and if the resulting compound would have been the predictable result of the linkage procedure. Thus, Office personnel should recognize that in certain situations, it may be proper to reject a claimed chemical compound as obvious even without identifying a single lead compound.

Obviousness of a chemical compound in view of its structural similarity to a prior art compound may be shown by identifying some line of reasoning that would have led one of ordinary skill in the art to select and modify the prior art compound in a particular way to produce the claimed compound. The necessary line of reasoning can be drawn from any number of sources and need not necessarily be explicitly found in the prior art of record. The Federal Circuit determined that ample evidence supported the district court’s finding that compound 12 was a natural choice for further development. For example, Altana’s prior art patent claimed that its compounds, including compound 12, were improvements over the prior art; compound 12 was disclosed as one of the more potent of the eighteen compounds disclosed; the patent examiner had considered the compounds of Altana’s prior art patent to be relevant during the prosecution of the patent in suit; and experts had opined that one of ordinary skill in the art would have selected the eighteen compounds to pursue further investigation into their potential as proton pump inhibitors.

To reject a claim based on this rationale, Office personnel must resolve the Graham factual inquiries. Then, Office personnel must articulate the following:
…
(4) whatever additional findings based on the Graham factual inquiries may be necessary, in view of the facts of the case under consideration, to explain a conclusion of obviousness.

To reject a claim based on this rationale, Office personnel must resolve the Graham factual inquiries. Then, Office personnel must articulate the following:
…
(4) whatever additional findings based on the Graham factual inquiries may be necessary, in view of the facts of the case under consideration, to explain a conclusion of obviousness.

To reject a claim based on this rationale, Office personnel must resolve the Graham factual inquiries. Then, Office personnel must articulate the following:
…
(4) whatever additional findings based on the Graham factual inquiries may be necessary, in view of the facts of the case under consideration, to explain a conclusion of obviousness.

To reject a claim based on this rationale, Office personnel must resolve the Graham factual inquiries. Then, Office personnel must articulate the following:
…
(5) whatever additional findings based on the Graham factual inquiries may be necessary, in view of the facts of the case under consideration, to explain a conclusion of obviousness.

To reject a claim based on this rationale, Office personnel must resolve the Graham factual inquiries. Then, Office personnel must articulate the following:
…
(3) whatever additional findings based on the Graham factual inquiries may be necessary, in view of the facts of the case under consideration, to explain a conclusion of obviousness.

The rationale to support a conclusion that the claim would have been obvious is that “a person of ordinary skill has good reason to pursue the known options within his or her technical grasp. If this leads to the anticipated success, it is likely that product [was] not of innovation but of ordinary skill and common sense. In that instance the fact that a combination was obvious to try might show that it was obvious under § 103.” KSR, 550 U.S. at 421, 82 USPQ2d at 1397. If any of these findings cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.

The question of whether a claimed invention can be shown to be obvious based on an “obvious to try” line of reasoning has been explored extensively by the Federal Circuit in several cases since the KSR decision. The case law in this area is developing quickly in the chemical arts, although the rationale has been applied in other art areas as well.

The Federal Circuit pointed out the challenging nature of the task faced by the courts – and likewise by Office personnel – when considering the viability of an obvious to try argument: “The evaluation of the choices made by a skilled scientist, when such choices lead to the desired result, is a challenge to judicial understanding of how technical advance is achieved in the particular field of science or technology.” Abbott Labs. v. Sandoz, Inc., 544 F.3d 1341, 1352, 89 USPQ2d 1161, 1171 (Fed. Cir. 2008). The Federal Circuit cautioned that an obviousness inquiry based on an obvious to try rationale must always be undertaken in the context of the subject matter in question, “including the characteristics of the science or technology, its state of advance, the nature of the known choices, the specificity or generality of the prior art, and the predictability of results in the area of interest.” Id.

The Federal Circuit pointed out the challenging nature of the task faced by the courts – and likewise by Office personnel – when considering the viability of an obvious to try argument: “The evaluation of the choices made by a skilled scientist, when such choices lead to the desired result, is a challenge to judicial understanding of how technical advance is achieved in the particular field of science or technology.” Abbott Labs. v. Sandoz, Inc., 544 F.3d 1341, 1352, 89 USPQ2d 1161, 1171 (Fed. Cir. 2008). The Federal Circuit cautioned that an obviousness inquiry based on an obvious to try rationale must always be undertaken in the context of the subject matter in question, “including the characteristics of the science or technology, its state of advance, the nature of the known choices, the specificity or generality of the prior art, and the predictability of results in the area of interest.” Id.

Relying on In re Deuel, 51 F.3d 1552, 34 USPQ2d 1210 (Fed. Cir. 1995), appellant argued that it was improper for the Office to use the polypeptide of the Valiante patent together with the methods described in Sambrook to reject a claim drawn to a specific nucleic acid molecule without providing a reference showing or suggesting a structurally similar nucleic acid molecule. Citing KSR, the Board stated that “when there is motivation to solve a problem and there are a finite number of identified, predictable solutions, a person of ordinary skill has good reason to pursue the known options within his or her technical grasp. If this leads to anticipated success, it is likely the product not of innovation but of ordinary skill and common sense.” KSR, 550 U.S. at 402-03, 82 USPQ2d at 1390. The Board noted that the problem facing those in the art was to isolate a specific nucleic acid, and there were a limited number of methods available to do so. The Board concluded that the skilled artisan would have had reason to try these methods with the reasonable expectation that at least one would be successful. Thus, isolating the specific nucleic acid molecule claimed was “the product not of innovation but of ordinary skill and common sense.” Id.

Relying on In re Deuel, 51 F.3d 1552, 34 USPQ2d 1210 (Fed. Cir. 1995), appellant argued that it was improper for the Office to use the polypeptide of the Valiante patent together with the methods described in Sambrook to reject a claim drawn to a specific nucleic acid molecule without providing a reference showing or suggesting a structurally similar nucleic acid molecule. Citing KSR, the Board stated that “when there is motivation to solve a problem and there are a finite number of identified, predictable solutions, a person of ordinary skill has good reason to pursue the known options within his or her technical grasp. If this leads to anticipated success, it is likely the product not of innovation but of ordinary skill and common sense.” KSR, 550 U.S. at 402-03, 82 USPQ2d at 1390. The Board noted that the problem facing those in the art was to isolate a specific nucleic acid, and there were a limited number of methods available to do so. The Board concluded that the skilled artisan would have had reason to try these methods with the reasonable expectation that at least one would be successful. Thus, isolating the specific nucleic acid molecule claimed was “the product not of innovation but of ordinary skill and common sense.” Id.

The Board’s reasoning was substantially adopted by the Federal Circuit. However, it is important to note that in the Kubin decision, the Federal Circuit held that “the Supreme Court in KSR unambiguously discredited” the Federal Circuit’s decision in Deuel, insofar as it “implies the obviousness inquiry cannot consider that the combination of the claim’s constituent elements was ‘obvious to try.’” Kubin, 561 F.3d at 1358, 90 USPQ2d at 1422. Instead, Kubin stated that KSR “resurrects” the Federal Circuit’s own wisdom in O’Farrell, in which “to differentiate between proper and improper applications of ‘obvious to try,’” the Federal Circuit “outlined two classes of situations where ‘obvious to try’ is erroneously equated with obviousness under § 103.” Kubin, 561 F.3d at 1359, 90 USPQ2d at 1423. These two classes of situations are: (1) when what would have been “obvious to try” would have been to vary all parameters or try each of numerous possible choices until one possibly arrived at a successful result, where the prior art gave either no indication of which parameters were critical or no direction as to which of many possible choices is likely to be successful; and (2) when what was “obvious to try” was to explore a new technology or general approach that seemed to be a promising field of experimentation, where the prior art gave only general guidance as to the particular form of the claimed invention or how to achieve it. Id. (citing In re O’Farrell, 853 F.2d 894, 903, 7 USPQ2d 1673, 1681 (Fed. Cir. 1988)).

The KSR Court recognized that “[w]hen there is a design need or market pressure to solve a problem and there are a finite number of identified, predictable solutions, a person of ordinary skill has good reason to pursue the known options within his or her technical grasp.” KSR, 550 U.S. at 421, 82 USPQ2d at 1397. In such circumstances, “the fact that a combination was obvious to try might show that it was obvious under § 103.” Id. That is not the case here. Rather than identify predictable solutions for antidiabetic treatment, the prior art disclosed a broad selection of compounds any one of which could have been selected as a lead compound for further investigation. Significantly, the closest prior art compound (compound b, the 6-methyl) exhibited negative properties that would have directed one of ordinary skill in the art away from that compound. Thus, this case fails to present the type of situation contemplated by the Court when it stated that an invention may be deemed obvious if it was “obvious to try.” The evidence showed that it was not obvious to try.

The KSR Court recognized that “[w]hen there is a design need or market pressure to solve a problem and there are a finite number of identified, predictable solutions, a person of ordinary skill has good reason to pursue the known options within his or her technical grasp.” KSR, 550 U.S. at 421, 82 USPQ2d at 1397. In such circumstances, “the fact that a combination was obvious to try might show that it was obvious under § 103.” Id. That is not the case here. Rather than identify predictable solutions for antidiabetic treatment, the prior art disclosed a broad selection of compounds any one of which could have been selected as a lead compound for further investigation. Significantly, the closest prior art compound (compound b, the 6-methyl) exhibited negative properties that would have directed one of ordinary skill in the art away from that compound. Thus, this case fails to present the type of situation contemplated by the Court when it stated that an invention may be deemed obvious if it was “obvious to try.” The evidence showed that it was not obvious to try.

The KSR Court recognized that “[w]hen there is a design need or market pressure to solve a problem and there are a finite number of identified, predictable solutions, a person of ordinary skill has good reason to pursue the known options within his or her technical grasp.” KSR, 550 U.S. at 421, 82 USPQ2d at 1397. In such circumstances, “the fact that a combination was obvious to try might show that it was obvious under § 103.” Id. That is not the case here. Rather than identify predictable solutions for antidiabetic treatment, the prior art disclosed a broad selection of compounds any one of which could have been selected as a lead compound for further investigation. Significantly, the closest prior art compound (compound b, the 6-methyl) exhibited negative properties that would have directed one of ordinary skill in the art away from that compound. Thus, this case fails to present the type of situation contemplated by the Court when it stated that an invention may be deemed obvious if it was “obvious to try.” The evidence showed that it was not obvious to try.

Accordingly, Office personnel should recognize that the obvious to try rationale does not apply when the appropriate factual findings cannot be made. In Takeda, there was a recognized need for treatment of diabetes. However, there was no finite number of identified, predictable solutions to the recognized need, and no reasonable expectation of success. There were numerous known TZD compounds, and although one clearly represented the closest prior art, its known disadvantages rendered it unsuitable as a starting point for further research, and taught the skilled artisan away from its use. Furthermore, even if there had been reason to select compound b, there had been no reasonable expectation of success associated with the particular modifications necessary to transform compound b into the claimed compound pioglitazone. Thus, an obviousness rejection based on an obvious to try rationale was not appropriate in this situation.

Accordingly, Office personnel should recognize that the obvious to try rationale does not apply when the appropriate factual findings cannot be made. In Takeda, there was a recognized need for treatment of diabetes. However, there was no finite number of identified, predictable solutions to the recognized need, and no reasonable expectation of success. There were numerous known TZD compounds, and although one clearly represented the closest prior art, its known disadvantages rendered it unsuitable as a starting point for further research, and taught the skilled artisan away from its use. Furthermore, even if there had been reason to select compound b, there had been no reasonable expectation of success associated with the particular modifications necessary to transform compound b into the claimed compound pioglitazone. Thus, an obviousness rejection based on an obvious to try rationale was not appropriate in this situation.

Accordingly, Office personnel should recognize that the obvious to try rationale does not apply when the appropriate factual findings cannot be made. In Takeda, there was a recognized need for treatment of diabetes. However, there was no finite number of identified, predictable solutions to the recognized need, and no reasonable expectation of success. There were numerous known TZD compounds, and although one clearly represented the closest prior art, its known disadvantages rendered it unsuitable as a starting point for further research, and taught the skilled artisan away from its use. Furthermore, even if there had been reason to select compound b, there had been no reasonable expectation of success associated with the particular modifications necessary to transform compound b into the claimed compound pioglitazone. Thus, an obviousness rejection based on an obvious to try rationale was not appropriate in this situation.

Thus, Ortho-McNeil helps to clarify the Supreme Court’s requirement in KSR for “a finite number” of predictable solutions when an obvious to try rationale is applied: under the Federal Circuit’s case law “finite” means “small or easily traversed” in the context of the art in question. As taught in Abbott, discussed above, it is essential that the inquiry be placed in the context of the subject matter at issue, and each case must be decided on its own facts.

The case of Sanofi-Synthelabo v. Apotex, Inc., 550 F.3d 1075, 89 USPQ2d 1370 (Fed. Cir. 2008), also sheds light on the obvious to try line of reasoning. The claimed compound was clopidogrel, which is the dextrorotatory isomer of methyl alpha- 5(4,5,6,7-tetrahydro(3,2-c)thienopyridyl)(2-chlorophenyl)-acetate. Clopidogrel is an anti-thrombotic compound used to treat or prevent heart attack or stroke. The racemate, or mixture of dextrorotatory and levorotatory (D- and L-) isomers of the compound, was known in the prior art. The two forms had not previously been separated, and although the mixture was known to have anti-thrombotic properties, the extent to which each of the individual isomers contributed to the observed properties of the racemate was not known and was not predictable.

Office personnel should recognize that even when only a small number of possible choices exist, the obvious to try line of reasoning is not appropriate when, upon consideration of all of the evidence, the outcome would not have been reasonably predictable and the inventor would not have had a reasonable expectation of success. In Bayer, there were art-based reasons to expect that both the normal pill and the enteric-coated pill would be therapeutically suitable, even though not all prior art studies were in complete agreement. Thus, the result obtained was not unexpected. In Sanofi, on the other hand, there was strong evidence that persons of ordinary skill in the art, prior to the separation of the isomers, would have had no reason to expect that the D-isomer would have such strong therapeutic advantages as compared with the L-isomer. In other words, the result in Sanofi was unexpected.

United had argued that it would have been obvious for a person of ordinary skill in the art to try a fan blade design in which the sweep angle in the outer region was reversed as compared with prior art fan blades from rearward to forward sweep, in order to reduce endwall shock. The Federal Circuit disagreed with United’s assessment that the claimed fan blade would have been obvious based on an obvious to try rationale. The Federal Circuit pointed out that in a proper obvious to try approach to obviousness, the possible options for solving a problem must have been “known and finite.” Id. at 1339, 95 USPQ2d at 1107 (citing Abbott, 544 F.3d at 1351, 89 USPQ2d at 1171). In this case, nothing in the prior art would have suggested that changing the sweep angle as Rolls-Royce had done would have addressed the issue of endwall shock. Thus, the Federal Circuit concluded that changing the sweep angle “would not have presented itself as an option at all, let alone an option that would have been obvious to try.” Id. The decision in Rolls-Royce is a reminder to Office personnel that the obvious to try rationale can properly be used to support a conclusion of obviousness only when the claimed solution would have been selected from a finite number of potential solutions known to persons of ordinary skill in the art.

United had argued that it would have been obvious for a person of ordinary skill in the art to try a fan blade design in which the sweep angle in the outer region was reversed as compared with prior art fan blades from rearward to forward sweep, in order to reduce endwall shock. The Federal Circuit disagreed with United’s assessment that the claimed fan blade would have been obvious based on an obvious to try rationale. The Federal Circuit pointed out that in a proper obvious to try approach to obviousness, the possible options for solving a problem must have been “known and finite.” Id. at 1339, 95 USPQ2d at 1107 (citing Abbott, 544 F.3d at 1351, 89 USPQ2d at 1171). In this case, nothing in the prior art would have suggested that changing the sweep angle as Rolls-Royce had done would have addressed the issue of endwall shock. Thus, the Federal Circuit concluded that changing the sweep angle “would not have presented itself as an option at all, let alone an option that would have been obvious to try.” Id. The decision in Rolls-Royce is a reminder to Office personnel that the obvious to try rationale can properly be used to support a conclusion of obviousness only when the claimed solution would have been selected from a finite number of potential solutions known to persons of ordinary skill in the art.

United had argued that it would have been obvious for a person of ordinary skill in the art to try a fan blade design in which the sweep angle in the outer region was reversed as compared with prior art fan blades from rearward to forward sweep, in order to reduce endwall shock. The Federal Circuit disagreed with United’s assessment that the claimed fan blade would have been obvious based on an obvious to try rationale. The Federal Circuit pointed out that in a proper obvious to try approach to obviousness, the possible options for solving a problem must have been “known and finite.” Id. at 1339, 95 USPQ2d at 1107 (citing Abbott, 544 F.3d at 1351, 89 USPQ2d at 1171). In this case, nothing in the prior art would have suggested that changing the sweep angle as Rolls-Royce had done would have addressed the issue of endwall shock. Thus, the Federal Circuit concluded that changing the sweep angle “would not have presented itself as an option at all, let alone an option that would have been obvious to try.” Id. The decision in Rolls-Royce is a reminder to Office personnel that the obvious to try rationale can properly be used to support a conclusion of obviousness only when the claimed solution would have been selected from a finite number of potential solutions known to persons of ordinary skill in the art.

United had argued that it would have been obvious for a person of ordinary skill in the art to try a fan blade design in which the sweep angle in the outer region was reversed as compared with prior art fan blades from rearward to forward sweep, in order to reduce endwall shock. The Federal Circuit disagreed with United’s assessment that the claimed fan blade would have been obvious based on an obvious to try rationale. The Federal Circuit pointed out that in a proper obvious to try approach to obviousness, the possible options for solving a problem must have been “known and finite.” Id. at 1339, 95 USPQ2d at 1107 (citing Abbott, 544 F.3d at 1351, 89 USPQ2d at 1171). In this case, nothing in the prior art would have suggested that changing the sweep angle as Rolls-Royce had done would have addressed the issue of endwall shock. Thus, the Federal Circuit concluded that changing the sweep angle “would not have presented itself as an option at all, let alone an option that would have been obvious to try.” Id. The decision in Rolls-Royce is a reminder to Office personnel that the obvious to try rationale can properly be used to support a conclusion of obviousness only when the claimed solution would have been selected from a finite number of potential solutions known to persons of ordinary skill in the art.

The case of Perfect Web Tech., Inc. v. InfoUSA, Inc., 587 F.3d 1324, 1328-29, 92 USPQ2d 1849, 1854 (Fed. Cir. 2009), provides an example in which the Federal Circuit held that a claimed method for managing bulk email distribution was obvious on the basis of an obvious to try argument. In Perfect Web, the method required selecting the intended recipients, transmitting the emails, determining how many of the emails had been successfully received, and repeating the first three steps if a pre-determined minimum number of intended recipients had not received the email.

The Federal Circuit noted that based on “simple logic,” selecting a new list of recipients was more likely to result in the desired outcome than resending to those who had not received the email on the first attempt. There had been no evidence of any unexpected result associated with selecting a new recipient list, and no evidence that the method would not have had a reasonable likelihood of success. Thus, the Federal Circuit concluded that, as required by KSR, there were a “finite number of identified, predictable solutions,” and that the obvious to try inquiry properly led to the legal conclusion of obviousness.

The rationale to support a conclusion that the claim would have been obvious is that all the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination yielded nothing more than predictable results to one of ordinary skill in the art. KSR, 550 U.S. at 416, 82 USPQ2d at 1395; B/E Aerospace, Inc. v. C&D Zodiac, Inc., 962 F.3d 1373, 1379, 2020 USPQ2d 10706 (Fed. Cir. 2020); Sakraida v. AG Pro, Inc., 425 U.S. 273, 282, 189 USPQ 449, 453 (1976); Anderson’s-Black Rock, Inc. v. Pavement Salvage Co., 396 U.S. 57, 62-63, 163 USPQ 673, 675 (1969); Great Atl. & P. Tea Co. v. Supermarket Equip. Corp., 340 U.S. 147, 152, 87 USPQ 303, 306 (1950). “[I]t can be important to identify a reason that would have prompted a person of ordinary skill in the relevant field to combine the elements in the way the claimed new invention does.” KSR, 550 U.S. at 418, 82 USPQ2d at 1396. If any of these findings cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.

The rationale to support a conclusion that the claim would have been obvious is that all the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination yielded nothing more than predictable results to one of ordinary skill in the art. KSR, 550 U.S. at 416, 82 USPQ2d at 1395; B/E Aerospace, Inc. v. C&D Zodiac, Inc., 962 F.3d 1373, 1379, 2020 USPQ2d 10706 (Fed. Cir. 2020); Sakraida v. AG Pro, Inc., 425 U.S. 273, 282, 189 USPQ 449, 453 (1976); Anderson’s-Black Rock, Inc. v. Pavement Salvage Co., 396 U.S. 57, 62-63, 163 USPQ 673, 675 (1969); Great Atl. & P. Tea Co. v. Supermarket Equip. Corp., 340 U.S. 147, 152, 87 USPQ 303, 306 (1950). “[I]t can be important to identify a reason that would have prompted a person of ordinary skill in the relevant field to combine the elements in the way the claimed new invention does.” KSR, 550 U.S. at 418, 82 USPQ2d at 1396. If any of these findings cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.

Note that combining known prior art elements is not sufficient to render the claimed invention obvious if the results would not have been predictable to one of ordinary skill in the art. United States v. Adams, 383 U.S. 39, 51-52, 148 USPQ 479, 483-84 (1966). In Adams, the claimed invention was to a battery with one magnesium electrode and one cuprous chloride electrode that could be stored dry and activated by the addition of plain water or salt water. Although magnesium and cuprous chloride were individually known battery components, the Court concluded that the claimed battery was nonobvious. The Court stated that “[d]espite the fact that each of the elements of the Adams battery was well known in the prior art, to combine them as did Adams required that a person reasonably skilled in the prior art must ignore” the teaching away of the prior art that such batteries were impractical and that water-activated batteries were successful only when combined with electrolytes detrimental to the use of magnesium electrodes. Id. at 42-43, 50-52, 148 USPQ at 480, 483. “[W]hen the prior art teaches away from combining certain known elements, discovery of successful means of combining them is more likely to be nonobvious.” KSR, 550 U.S. at 416, 82 USPQ2d at 1395.

Note that combining known prior art elements is not sufficient to render the claimed invention obvious if the results would not have been predictable to one of ordinary skill in the art. United States v. Adams, 383 U.S. 39, 51-52, 148 USPQ 479, 483-84 (1966). In Adams, the claimed invention was to a battery with one magnesium electrode and one cuprous chloride electrode that could be stored dry and activated by the addition of plain water or salt water. Although magnesium and cuprous chloride were individually known battery components, the Court concluded that the claimed battery was nonobvious. The Court stated that “[d]espite the fact that each of the elements of the Adams battery was well known in the prior art, to combine them as did Adams required that a person reasonably skilled in the prior art must ignore” the teaching away of the prior art that such batteries were impractical and that water-activated batteries were successful only when combined with electrolytes detrimental to the use of magnesium electrodes. Id. at 42-43, 50-52, 148 USPQ at 480, 483. “[W]hen the prior art teaches away from combining certain known elements, discovery of successful means of combining them is more likely to be nonobvious.” KSR, 550 U.S. at 416, 82 USPQ2d at 1395.

Note that combining known prior art elements is not sufficient to render the claimed invention obvious if the results would not have been predictable to one of ordinary skill in the art. United States v. Adams, 383 U.S. 39, 51-52, 148 USPQ 479, 483-84 (1966). In Adams, the claimed invention was to a battery with one magnesium electrode and one cuprous chloride electrode that could be stored dry and activated by the addition of plain water or salt water. Although magnesium and cuprous chloride were individually known battery components, the Court concluded that the claimed battery was nonobvious. The Court stated that “[d]espite the fact that each of the elements of the Adams battery was well known in the prior art, to combine them as did Adams required that a person reasonably skilled in the prior art must ignore” the teaching away of the prior art that such batteries were impractical and that water-activated batteries were successful only when combined with electrolytes detrimental to the use of magnesium electrodes. Id. at 42-43, 50-52, 148 USPQ at 480, 483. “[W]hen the prior art teaches away from combining certain known elements, discovery of successful means of combining them is more likely to be nonobvious.” KSR, 550 U.S. at 416, 82 USPQ2d at 1395.

KSR and our later cases establish that the legal determination of obviousness may include recourse to logic, judgment, and common sense, in lieu of expert testimony…. Thus, in appropriate cases, the ultimate inference as to the existence of a motivation to combine references may boil down to a question of “common sense,” appropriate for resolution on summary judgment or JMOL.

The rationale to support a conclusion that the claim would have been obvious is that the substitution of one known element for another yields predictable results to one of ordinary skill in the art. If any of these findings cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.

The rationale to support a conclusion that the claim would have been obvious is that a method of enhancing a particular class of devices (methods, or products) has been made part of the ordinary capabilities of one skilled in the art based upon the teaching of such improvement in other situations. One of ordinary skill in the art would have been capable of applying this known method of enhancement to a “base” device (method, or product) in the prior art and the results would have been predictable to one of ordinary skill in the art. “It's enough … to show that there was a known problem … in the art, that [another reference] … helped address that issue, and that combining the teachings of [the two references] wasn't beyond the skill of an ordinary artisan. Nothing more is required to show a motivation to combine under KSR. ” See Intel Corp. v. PACT XPP Schweiz AG, 61 F.4th 1373, 1380-81, 2023 USPQ2d 297 (Fed. Cir. 2023) (finding that both prior art references “address the same problem and that [the secondary reference’s] cache was a known way to address that problem is precisely the reason that there's a motivation to combine under KSR and our precedent.”).

The rationale to support a conclusion that the claim would have been obvious is that a method of enhancing a particular class of devices (methods, or products) has been made part of the ordinary capabilities of one skilled in the art based upon the teaching of such improvement in other situations. One of ordinary skill in the art would have been capable of applying this known method of enhancement to a “base” device (method, or product) in the prior art and the results would have been predictable to one of ordinary skill in the art. “It's enough … to show that there was a known problem … in the art, that [another reference] … helped address that issue, and that combining the teachings of [the two references] wasn't beyond the skill of an ordinary artisan. Nothing more is required to show a motivation to combine under KSR. ” See Intel Corp. v. PACT XPP Schweiz AG, 61 F.4th 1373, 1380-81, 2023 USPQ2d 297 (Fed. Cir. 2023) (finding that both prior art references “address the same problem and that [the secondary reference’s] cache was a known way to address that problem is precisely the reason that there's a motivation to combine under KSR and our precedent.”).

The claimed invention in In re Urbanski, 809 F.3d 1237, 1244, 117 USPQ2d 1499, 1504 (Fed. Cir. 2016) was directed to a method of enzymatic hydrolysis of soy fiber to reduce water holding capacity, requiring reacting the soy fiber and enzyme in water for about 60-120 minutes. The claims were rejected over two references, wherein the primary reference, Gross, taught using a reaction time of 5 to 72 hours and the secondary reference, Wong, taught using a reaction time of 100 to 240 minutes, preferably 120 minutes. The applicant argued that modifying the primary reference in the manner suggested by the secondary reference would forego the benefits taught by the primary reference, thereby teaching away from the combination. The court found there was sufficient motivation to combine because both references recognized reaction time and degree of hydrolysis as result-effective variables, which can be varied to have a predictable effect on the final product; and the primary reference does not contain an express teaching away from the proposed modification. “Substantial evidence thus supports the Board’s finding that a person of ordinary skill would have been motivated to modify the Gross process by using a shorter reaction time, in order to obtain the favorable properties disclosed in Wong.”

The rationale to support a conclusion that the claim would have been obvious is that all the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination yielded nothing more than predictable results to one of ordinary skill in the art. KSR, 550 U.S. at 416, 82 USPQ2d at 1395; B/E Aerospace, Inc. v. C&D Zodiac, Inc., 962 F.3d 1373, 1379, 2020 USPQ2d 10706 (Fed. Cir. 2020); Sakraida v. AG Pro, Inc., 425 U.S. 273, 282, 189 USPQ 449, 453 (1976); Anderson’s-Black Rock, Inc. v. Pavement Salvage Co., 396 U.S. 57, 62-63, 163 USPQ 673, 675 (1969); Great Atl. & P. Tea Co. v. Supermarket Equip. Corp., 340 U.S. 147, 152, 87 USPQ 303, 306 (1950). “[I]t can be important to identify a reason that would have prompted a person of ordinary skill in the relevant field to combine the elements in the way the claimed new invention does.” KSR, 550 U.S. at 418, 82 USPQ2d at 1396. If any of these findings cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.

The rationale to support a conclusion that the claim would have been obvious is that all the claimed elements were known in the prior art and one skilled in the art could have combined the elements as claimed by known methods with no change in their respective functions, and the combination yielded nothing more than predictable results to one of ordinary skill in the art. KSR, 550 U.S. at 416, 82 USPQ2d at 1395; B/E Aerospace, Inc. v. C&D Zodiac, Inc., 962 F.3d 1373, 1379, 2020 USPQ2d 10706 (Fed. Cir. 2020); Sakraida v. AG Pro, Inc., 425 U.S. 273, 282, 189 USPQ 449, 453 (1976); Anderson’s-Black Rock, Inc. v. Pavement Salvage Co., 396 U.S. 57, 62-63, 163 USPQ 673, 675 (1969); Great Atl. & P. Tea Co. v. Supermarket Equip. Corp., 340 U.S. 147, 152, 87 USPQ 303, 306 (1950). “[I]t can be important to identify a reason that would have prompted a person of ordinary skill in the relevant field to combine the elements in the way the claimed new invention does.” KSR, 550 U.S. at 418, 82 USPQ2d at 1396. If any of these findings cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.

Note that combining known prior art elements is not sufficient to render the claimed invention obvious if the results would not have been predictable to one of ordinary skill in the art. United States v. Adams, 383 U.S. 39, 51-52, 148 USPQ 479, 483-84 (1966). In Adams, the claimed invention was to a battery with one magnesium electrode and one cuprous chloride electrode that could be stored dry and activated by the addition of plain water or salt water. Although magnesium and cuprous chloride were individually known battery components, the Court concluded that the claimed battery was nonobvious. The Court stated that “[d]espite the fact that each of the elements of the Adams battery was well known in the prior art, to combine them as did Adams required that a person reasonably skilled in the prior art must ignore” the teaching away of the prior art that such batteries were impractical and that water-activated batteries were successful only when combined with electrolytes detrimental to the use of magnesium electrodes. Id. at 42-43, 50-52, 148 USPQ at 480, 483. “[W]hen the prior art teaches away from combining certain known elements, discovery of successful means of combining them is more likely to be nonobvious.” KSR, 550 U.S. at 416, 82 USPQ2d at 1395.

The court then turned to the question of whether there would have been adequate motivation to combine the prior art elements as had been urged by Master Lock. The court recalled the Graham inquiries, and also emphasized the “expansive and flexible” post-KSR approach to obviousness that must not “deny factfinders recourse to common sense.” Id. at 1238, 95 USPQ2d at 1530-31. (quoting KSR, 550 U.S. at 415, 421, 82 USPQ2d at 1395, 1397). The court stated:

The rationale to support a conclusion that the claim would have been obvious is that “a person of ordinary skill has good reason to pursue the known options within his or her technical grasp. If this leads to the anticipated success, it is likely that product [was] not of innovation but of ordinary skill and common sense. In that instance the fact that a combination was obvious to try might show that it was obvious under § 103.” KSR, 550 U.S. at 421, 82 USPQ2d at 1397. If any of these findings cannot be made, then this rationale cannot be used to support a conclusion that the claim would have been obvious to one of ordinary skill in the art.

Relying on In re Deuel, 51 F.3d 1552, 34 USPQ2d 1210 (Fed. Cir. 1995), appellant argued that it was improper for the Office to use the polypeptide of the Valiante patent together with the methods described in Sambrook to reject a claim drawn to a specific nucleic acid molecule without providing a reference showing or suggesting a structurally similar nucleic acid molecule. Citing KSR, the Board stated that “when there is motivation to solve a problem and there are a finite number of identified, predictable solutions, a person of ordinary skill has good reason to pursue the known options within his or her technical grasp. If this leads to anticipated success, it is likely the product not of innovation but of ordinary skill and common sense.” KSR, 550 U.S. at 402-03, 82 USPQ2d at 1390. The Board noted that the problem facing those in the art was to isolate a specific nucleic acid, and there were a limited number of methods available to do so. The Board concluded that the skilled artisan would have had reason to try these methods with the reasonable expectation that at least one would be successful. Thus, isolating the specific nucleic acid molecule claimed was “the product not of innovation but of ordinary skill and common sense.” Id.

The KSR Court recognized that “[w]hen there is a design need or market pressure to solve a problem and there are a finite number of identified, predictable solutions, a person of ordinary skill has good reason to pursue the known options within his or her technical grasp.” KSR, 550 U.S. at 421, 82 USPQ2d at 1397. In such circumstances, “the fact that a combination was obvious to try might show that it was obvious under § 103.” Id. That is not the case here. Rather than identify predictable solutions for antidiabetic treatment, the prior art disclosed a broad selection of compounds any one of which could have been selected as a lead compound for further investigation. Significantly, the closest prior art compound (compound b, the 6-methyl) exhibited negative properties that would have directed one of ordinary skill in the art away from that compound. Thus, this case fails to present the type of situation contemplated by the Court when it stated that an invention may be deemed obvious if it was “obvious to try.” The evidence showed that it was not obvious to try.

The KSR Court recognized that “[w]hen there is a design need or market pressure to solve a problem and there are a finite number of identified, predictable solutions, a person of ordinary skill has good reason to pursue the known options within his or her technical grasp.” KSR, 550 U.S. at 421, 82 USPQ2d at 1397. In such circumstances, “the fact that a combination was obvious to try might show that it was obvious under § 103.” Id. That is not the case here. Rather than identify predictable solutions for antidiabetic treatment, the prior art disclosed a broad selection of compounds any one of which could have been selected as a lead compound for further investigation. Significantly, the closest prior art compound (compound b, the 6-methyl) exhibited negative properties that would have directed one of ordinary skill in the art away from that compound. Thus, this case fails to present the type of situation contemplated by the Court when it stated that an invention may be deemed obvious if it was “obvious to try.” The evidence showed that it was not obvious to try.

The case of Sanofi-Synthelabo v. Apotex, Inc., 550 F.3d 1075, 89 USPQ2d 1370 (Fed. Cir. 2008), also sheds light on the obvious to try line of reasoning. The claimed compound was clopidogrel, which is the dextrorotatory isomer of methyl alpha- 5(4,5,6,7-tetrahydro(3,2-c)thienopyridyl)(2-chlorophenyl)-acetate. Clopidogrel is an anti-thrombotic compound used to treat or prevent heart attack or stroke. The racemate, or mixture of dextrorotatory and levorotatory (D- and L-) isomers of the compound, was known in the prior art. The two forms had not previously been separated, and although the mixture was known to have anti-thrombotic properties, the extent to which each of the individual isomers contributed to the observed properties of the racemate was not known and was not predictable.

The Supreme Court in KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395-97 (2007) identified a number of rationales to support a conclusion of obviousness which are consistent with the proper “functional approach” to the determination of obviousness as laid down in Graham. The key to supporting any rejection under 35 U.S.C. 103 is the clear articulation of the reason(s) why the claimed invention would have been obvious. The Supreme Court in KSR noted that the analysis supporting a rejection under 35 U.S.C. 103 should be made explicit. In Ball Aerosol v. Ltd. Brands, 555 F.3d 984, 89 USPQ2d 1870 (Fed. Cir. 2009), the Federal Circuit offered additional instruction as to the need for an explicit analysis. The Federal Circuit explained that the Supreme Court’s requirement for an explicit analysis does not require record evidence of an explicit teaching of a motivation to combine in the prior art.

To reject a claim based on this rationale, Office personnel must resolve the Graham factual inquiries. Then, Office personnel must articulate the following:

• (1) a finding that the prior art included each element claimed, although not necessarily in a single prior art reference, with the only difference between the claimed invention and the prior art being the lack of actual combination of the elements in a single prior art reference;
• (2) a finding that one of ordinary skill in the art could have combined the elements as claimed by known methods, and that in combination, each element merely performs the same function as it does separately;
• (3) a finding that one of ordinary skill in the art would have recognized that the results of the combination were predictable; and
• (4) whatever additional findings based on the Graham factual inquiries may be necessary, in view of the facts of the case under consideration, to explain a conclusion of obviousness.

To reject a claim based on this rationale, Office personnel must resolve the Graham factual inquiries. Then, Office personnel must articulate the following:

• (1) a finding that the prior art contained a device (method, product, etc.) which differed from the claimed device by the substitution of some components (step, element, etc.) with other components;
• (2) a finding that the substituted components and their functions were known in the art;
• (3) a finding that one of ordinary skill in the art could have substituted one known element for another, and the results of the substitution would have been predictable; and
• (4) whatever additional findings based on the Graham factual inquiries may be necessary, in view of the facts of the case under consideration, to explain a conclusion of obviousness.

To reject a claim based on this rationale, Office personnel must resolve the Graham factual inquiries. Then, Office personnel must articulate the following:

• (1) a finding that the prior art contained a “base” device (method, or product) upon which the claimed invention can be seen as an “improvement;”
• (2) a finding that the prior art contained a “comparable” device (method, or product that is not the same as the base device) that has been improved in the same way as the claimed invention;
• (3) a finding that one of ordinary skill in the art could have applied the known “improvement” technique in the same way to the “base” device (method, or product) and the results would have been predictable to one of ordinary skill in the art; and
• (4) whatever additional findings based on the Graham factual inquiries may be necessary, in view of the facts of the case under consideration, to explain a conclusion of obviousness.

To reject a claim based on this rationale, Office personnel must resolve the Graham factual inquiries. Then, Office personnel must articulate the following:

• (1) a finding that the prior art contained a “base” device (method, or product) upon which the claimed invention can be seen as an “improvement;”
• (2) a finding that the prior art contained a known technique that is applicable to the base device (method, or product);
• (3) a finding that one of ordinary skill in the art would have recognized that applying the known technique would have yielded predictable results and resulted in an improved system; and
• (4) whatever additional findings based on the Graham factual inquiries may be necessary, in view of the facts of the case under consideration, to explain a conclusion of obviousness.

To reject a claim based on this rationale, Office personnel must resolve the Graham factual inquiries. Then, Office personnel must articulate the following:

• (1) a finding that at the relevant time, there had been a recognized problem or need in the art, which may include a design need or market pressure to solve a problem;
• (2) a finding that there had been a finite number of identified, predictable potential solutions to the recognized need or problem;
• (3) a finding that one of ordinary skill in the art could have pursued the known potential solutions with a reasonable expectation of success; and
• (4) whatever additional findings based on the Graham factual inquiries may be necessary, in view of the facts of the case under consideration, to explain a conclusion of obviousness.

To reject a claim based on this rationale, Office personnel must resolve the Graham factual inquiries. Then, Office personnel must articulate the following:

• (1) a finding that the scope and content of the prior art, whether in the same field of endeavor as that of the applicant’s invention or a different field of endeavor, included a similar or analogous device (method, or product);
• (2) a finding that there were design incentives or market forces which would have prompted adaptation of the known device (method, or product);
• (3) a finding that the differences between the claimed invention and the prior art were encompassed in known variations or in a principle known in the prior art;
• (4) a finding that one of ordinary skill in the art, in view of the identified design incentives or other market forces, could have implemented the claimed variation of the prior art, and the claimed variation would have been predictable to one of ordinary skill in the art; and
• (5) whatever additional findings based on the Graham factual inquiries may be necessary, in view of the facts of the case under consideration, to explain a conclusion of obviousness.

To reject a claim based on this rationale, Office personnel must resolve the Graham factual inquiries. Then, Office personnel must articulate the following:

• (1) a finding that there was some teaching, suggestion, or motivation, either in the references themselves or in the knowledge generally available to one of ordinary skill in the art, to modify the reference or to combine reference teachings;
• (2) a finding that there was reasonable expectation of success; and
• (3) whatever additional findings based on the Graham factual inquiries may be necessary, in view of the facts of the case under consideration, to explain a conclusion of obviousness.

The Board’s reasoning was substantially adopted by the Federal Circuit. However, it is important to note that in the Kubin decision, the Federal Circuit held that “the Supreme Court in KSR unambiguously discredited” the Federal Circuit’s decision in Deuel, insofar as it “implies the obviousness inquiry cannot consider that the combination of the claim’s constituent elements was ‘obvious to try.’” Kubin, 561 F.3d at 1358, 90 USPQ2d at 1422. Instead, Kubin stated that KSR “resurrects” the Federal Circuit’s own wisdom in O’Farrell, in which “to differentiate between proper and improper applications of ‘obvious to try,’” the Federal Circuit “outlined two classes of situations where ‘obvious to try’ is erroneously equated with obviousness under § 103.” Kubin, 561 F.3d at 1359, 90 USPQ2d at 1423. These two classes of situations are: (1) when what would have been “obvious to try” would have been to vary all parameters or try each of numerous possible choices until one possibly arrived at a successful result, where the prior art gave either no indication of which parameters were critical or no direction as to which of many possible choices is likely to be successful; and (2) when what was “obvious to try” was to explore a new technology or general approach that seemed to be a promising field of experimentation, where the prior art gave only general guidance as to the particular form of the claimed invention or how to achieve it. Id. (citing In re O’Farrell, 853 F.2d 894, 903, 7 USPQ2d 1673, 1681 (Fed. Cir. 1988)).

The Board’s reasoning was substantially adopted by the Federal Circuit. However, it is important to note that in the Kubin decision, the Federal Circuit held that “the Supreme Court in KSR unambiguously discredited” the Federal Circuit’s decision in Deuel, insofar as it “implies the obviousness inquiry cannot consider that the combination of the claim’s constituent elements was ‘obvious to try.’” Kubin, 561 F.3d at 1358, 90 USPQ2d at 1422. Instead, Kubin stated that KSR “resurrects” the Federal Circuit’s own wisdom in O’Farrell, in which “to differentiate between proper and improper applications of ‘obvious to try,’” the Federal Circuit “outlined two classes of situations where ‘obvious to try’ is erroneously equated with obviousness under § 103.” Kubin, 561 F.3d at 1359, 90 USPQ2d at 1423. These two classes of situations are: (1) when what would have been “obvious to try” would have been to vary all parameters or try each of numerous possible choices until one possibly arrived at a successful result, where the prior art gave either no indication of which parameters were critical or no direction as to which of many possible choices is likely to be successful; and (2) when what was “obvious to try” was to explore a new technology or general approach that seemed to be a promising field of experimentation, where the prior art gave only general guidance as to the particular form of the claimed invention or how to achieve it. Id. (citing In re O’Farrell, 853 F.2d 894, 903, 7 USPQ2d 1673, 1681 (Fed. Cir. 1988)).

The Federal Circuit pointed out that application of common sense is not really an innovation in the law of obviousness when it stated, “Common sense has long been recognized to inform the analysis of obviousness if explained with sufficient reasoning.” Perfect Web, 587 F.3d at 1328, 92 USPQ2d at 1853 (emphasis added). The Federal Circuit then provided a review of a number of precedential cases that inform the understanding of common sense, including In re Bozek, 416 F.2d 1385, 1390, 163 USPQ 545, 549 (CCPA 1969) (explaining that a patent examiner may rely on “common knowledge and common sense of the person of ordinary skill in the art without any specific hint or suggestion in a particular reference”) and In re Zurko, 258 F.3d 1379, 1383, 1385, 59 USPQ2d 1693 at 1695, 1697 (Fed. Cir. 2001) (clarifying that a factual foundation is needed in order for an examiner to invoke “good common sense” in a case in which “basic knowledge and common sense was not based on any evidence in the record”). The Federal Circuit implicitly acknowledged in Perfect Web that the kind of strict evidence-based teaching, suggestion, or motivation required in In re Lee, 277 F.3d 1338, 1344, 61 USPQ2d 1430, 1434 (Fed. Cir. 2002), is not an absolute requirement for an obviousness rejection in light of the teachings of KSR. The Federal Circuit explained that “[a]t the time [of the Lee decision], we required the PTO to identify record evidence of a teaching, suggestion, or motivation to combine references.” However, Perfect Web went on to state that even under Lee, common sense could properly be applied when analyzing evidence relevant to obviousness. Citing DyStar Textilfarben GmbH v. C.H. Patrick Co., 464 F.3d 1356, 80 USPQ2d 1641 (Fed. Cir. 2006), and In re Kahn, 441 F.3d 977, 78 USPQ2d 1329 (Fed. Cir. 2006), two cases decided shortly before the Supreme Court’s decision in KSR, the Federal Circuit noted that although “a reasoned explanation that avoids conclusory generalizations” is required to use common sense, identification of a “specific hint or suggestion in a particular reference” is not. See also B/E Aerospace, Inc. v. C&D Zodiac, Inc., 962 F.3d 1373, 1380-81, 2020 USPQ2d 10706 (Fed. Cir. 2020) (stating that “the Board’s invocation of common sense was properly accompanied by reasoned analysis and evidentiary support” to show why it would be obvious to incorporate a second recess to receive an airplane seat support). But see Arendi v. Apple, 832 F.3d 1355, 119 USPQ2d 1822 (Fed. Cir. 2016) (finding that the Board had not provided a reasoned analysis, supported by the evidence of record, for why “common sense” taught the missing process step).

The Federal Circuit pointed out that application of common sense is not really an innovation in the law of obviousness when it stated, “Common sense has long been recognized to inform the analysis of obviousness if explained with sufficient reasoning.” Perfect Web, 587 F.3d at 1328, 92 USPQ2d at 1853 (emphasis added). The Federal Circuit then provided a review of a number of precedential cases that inform the understanding of common sense, including In re Bozek, 416 F.2d 1385, 1390, 163 USPQ 545, 549 (CCPA 1969) (explaining that a patent examiner may rely on “common knowledge and common sense of the person of ordinary skill in the art without any specific hint or suggestion in a particular reference”) and In re Zurko, 258 F.3d 1379, 1383, 1385, 59 USPQ2d 1693 at 1695, 1697 (Fed. Cir. 2001) (clarifying that a factual foundation is needed in order for an examiner to invoke “good common sense” in a case in which “basic knowledge and common sense was not based on any evidence in the record”). The Federal Circuit implicitly acknowledged in Perfect Web that the kind of strict evidence-based teaching, suggestion, or motivation required in In re Lee, 277 F.3d 1338, 1344, 61 USPQ2d 1430, 1434 (Fed. Cir. 2002), is not an absolute requirement for an obviousness rejection in light of the teachings of KSR. The Federal Circuit explained that “[a]t the time [of the Lee decision], we required the PTO to identify record evidence of a teaching, suggestion, or motivation to combine references.” However, Perfect Web went on to state that even under Lee, common sense could properly be applied when analyzing evidence relevant to obviousness. Citing DyStar Textilfarben GmbH v. C.H. Patrick Co., 464 F.3d 1356, 80 USPQ2d 1641 (Fed. Cir. 2006), and In re Kahn, 441 F.3d 977, 78 USPQ2d 1329 (Fed. Cir. 2006), two cases decided shortly before the Supreme Court’s decision in KSR, the Federal Circuit noted that although “a reasoned explanation that avoids conclusory generalizations” is required to use common sense, identification of a “specific hint or suggestion in a particular reference” is not. See also B/E Aerospace, Inc. v. C&D Zodiac, Inc., 962 F.3d 1373, 1380-81, 2020 USPQ2d 10706 (Fed. Cir. 2020) (stating that “the Board’s invocation of common sense was properly accompanied by reasoned analysis and evidentiary support” to show why it would be obvious to incorporate a second recess to receive an airplane seat support). But see Arendi v. Apple, 832 F.3d 1355, 119 USPQ2d 1822 (Fed. Cir. 2016) (finding that the Board had not provided a reasoned analysis, supported by the evidence of record, for why “common sense” taught the missing process step).

The Federal Circuit pointed out that application of common sense is not really an innovation in the law of obviousness when it stated, “Common sense has long been recognized to inform the analysis of obviousness if explained with sufficient reasoning.” Perfect Web, 587 F.3d at 1328, 92 USPQ2d at 1853 (emphasis added). The Federal Circuit then provided a review of a number of precedential cases that inform the understanding of common sense, including In re Bozek, 416 F.2d 1385, 1390, 163 USPQ 545, 549 (CCPA 1969) (explaining that a patent examiner may rely on “common knowledge and common sense of the person of ordinary skill in the art without any specific hint or suggestion in a particular reference”) and In re Zurko, 258 F.3d 1379, 1383, 1385, 59 USPQ2d 1693 at 1695, 1697 (Fed. Cir. 2001) (clarifying that a factual foundation is needed in order for an examiner to invoke “good common sense” in a case in which “basic knowledge and common sense was not based on any evidence in the record”). The Federal Circuit implicitly acknowledged in Perfect Web that the kind of strict evidence-based teaching, suggestion, or motivation required in In re Lee, 277 F.3d 1338, 1344, 61 USPQ2d 1430, 1434 (Fed. Cir. 2002), is not an absolute requirement for an obviousness rejection in light of the teachings of KSR. The Federal Circuit explained that “[a]t the time [of the Lee decision], we required the PTO to identify record evidence of a teaching, suggestion, or motivation to combine references.” However, Perfect Web went on to state that even under Lee, common sense could properly be applied when analyzing evidence relevant to obviousness. Citing DyStar Textilfarben GmbH v. C.H. Patrick Co., 464 F.3d 1356, 80 USPQ2d 1641 (Fed. Cir. 2006), and In re Kahn, 441 F.3d 977, 78 USPQ2d 1329 (Fed. Cir. 2006), two cases decided shortly before the Supreme Court’s decision in KSR, the Federal Circuit noted that although “a reasoned explanation that avoids conclusory generalizations” is required to use common sense, identification of a “specific hint or suggestion in a particular reference” is not. See also B/E Aerospace, Inc. v. C&D Zodiac, Inc., 962 F.3d 1373, 1380-81, 2020 USPQ2d 10706 (Fed. Cir. 2020) (stating that “the Board’s invocation of common sense was properly accompanied by reasoned analysis and evidentiary support” to show why it would be obvious to incorporate a second recess to receive an airplane seat support). But see Arendi v. Apple, 832 F.3d 1355, 119 USPQ2d 1822 (Fed. Cir. 2016) (finding that the Board had not provided a reasoned analysis, supported by the evidence of record, for why “common sense” taught the missing process step).

The Federal Circuit pointed out that application of common sense is not really an innovation in the law of obviousness when it stated, “Common sense has long been recognized to inform the analysis of obviousness if explained with sufficient reasoning.” Perfect Web, 587 F.3d at 1328, 92 USPQ2d at 1853 (emphasis added). The Federal Circuit then provided a review of a number of precedential cases that inform the understanding of common sense, including In re Bozek, 416 F.2d 1385, 1390, 163 USPQ 545, 549 (CCPA 1969) (explaining that a patent examiner may rely on “common knowledge and common sense of the person of ordinary skill in the art without any specific hint or suggestion in a particular reference”) and In re Zurko, 258 F.3d 1379, 1383, 1385, 59 USPQ2d 1693 at 1695, 1697 (Fed. Cir. 2001) (clarifying that a factual foundation is needed in order for an examiner to invoke “good common sense” in a case in which “basic knowledge and common sense was not based on any evidence in the record”). The Federal Circuit implicitly acknowledged in Perfect Web that the kind of strict evidence-based teaching, suggestion, or motivation required in In re Lee, 277 F.3d 1338, 1344, 61 USPQ2d 1430, 1434 (Fed. Cir. 2002), is not an absolute requirement for an obviousness rejection in light of the teachings of KSR. The Federal Circuit explained that “[a]t the time [of the Lee decision], we required the PTO to identify record evidence of a teaching, suggestion, or motivation to combine references.” However, Perfect Web went on to state that even under Lee, common sense could properly be applied when analyzing evidence relevant to obviousness. Citing DyStar Textilfarben GmbH v. C.H. Patrick Co., 464 F.3d 1356, 80 USPQ2d 1641 (Fed. Cir. 2006), and In re Kahn, 441 F.3d 977, 78 USPQ2d 1329 (Fed. Cir. 2006), two cases decided shortly before the Supreme Court’s decision in KSR, the Federal Circuit noted that although “a reasoned explanation that avoids conclusory generalizations” is required to use common sense, identification of a “specific hint or suggestion in a particular reference” is not. See also B/E Aerospace, Inc. v. C&D Zodiac, Inc., 962 F.3d 1373, 1380-81, 2020 USPQ2d 10706 (Fed. Cir. 2020) (stating that “the Board’s invocation of common sense was properly accompanied by reasoned analysis and evidentiary support” to show why it would be obvious to incorporate a second recess to receive an airplane seat support). But see Arendi v. Apple, 832 F.3d 1355, 119 USPQ2d 1822 (Fed. Cir. 2016) (finding that the Board had not provided a reasoned analysis, supported by the evidence of record, for why “common sense” taught the missing process step).

The Federal Circuit pointed out that application of common sense is not really an innovation in the law of obviousness when it stated, “Common sense has long been recognized to inform the analysis of obviousness if explained with sufficient reasoning.” Perfect Web, 587 F.3d at 1328, 92 USPQ2d at 1853 (emphasis added). The Federal Circuit then provided a review of a number of precedential cases that inform the understanding of common sense, including In re Bozek, 416 F.2d 1385, 1390, 163 USPQ 545, 549 (CCPA 1969) (explaining that a patent examiner may rely on “common knowledge and common sense of the person of ordinary skill in the art without any specific hint or suggestion in a particular reference”) and In re Zurko, 258 F.3d 1379, 1383, 1385, 59 USPQ2d 1693 at 1695, 1697 (Fed. Cir. 2001) (clarifying that a factual foundation is needed in order for an examiner to invoke “good common sense” in a case in which “basic knowledge and common sense was not based on any evidence in the record”). The Federal Circuit implicitly acknowledged in Perfect Web that the kind of strict evidence-based teaching, suggestion, or motivation required in In re Lee, 277 F.3d 1338, 1344, 61 USPQ2d 1430, 1434 (Fed. Cir. 2002), is not an absolute requirement for an obviousness rejection in light of the teachings of KSR. The Federal Circuit explained that “[a]t the time [of the Lee decision], we required the PTO to identify record evidence of a teaching, suggestion, or motivation to combine references.” However, Perfect Web went on to state that even under Lee, common sense could properly be applied when analyzing evidence relevant to obviousness. Citing DyStar Textilfarben GmbH v. C.H. Patrick Co., 464 F.3d 1356, 80 USPQ2d 1641 (Fed. Cir. 2006), and In re Kahn, 441 F.3d 977, 78 USPQ2d 1329 (Fed. Cir. 2006), two cases decided shortly before the Supreme Court’s decision in KSR, the Federal Circuit noted that although “a reasoned explanation that avoids conclusory generalizations” is required to use common sense, identification of a “specific hint or suggestion in a particular reference” is not. See also B/E Aerospace, Inc. v. C&D Zodiac, Inc., 962 F.3d 1373, 1380-81, 2020 USPQ2d 10706 (Fed. Cir. 2020) (stating that “the Board’s invocation of common sense was properly accompanied by reasoned analysis and evidentiary support” to show why it would be obvious to incorporate a second recess to receive an airplane seat support). But see Arendi v. Apple, 832 F.3d 1355, 119 USPQ2d 1822 (Fed. Cir. 2016) (finding that the Board had not provided a reasoned analysis, supported by the evidence of record, for why “common sense” taught the missing process step).

The Supreme Court in KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395-97 (2007) identified a number of rationales to support a conclusion of obviousness which are consistent with the proper “functional approach” to the determination of obviousness as laid down in Graham. The key to supporting any rejection under 35 U.S.C. 103 is the clear articulation of the reason(s) why the claimed invention would have been obvious. The Supreme Court in KSR noted that the analysis supporting a rejection under 35 U.S.C. 103 should be made explicit. In Ball Aerosol v. Ltd. Brands, 555 F.3d 984, 89 USPQ2d 1870 (Fed. Cir. 2009), the Federal Circuit offered additional instruction as to the need for an explicit analysis. The Federal Circuit explained that the Supreme Court’s requirement for an explicit analysis does not require record evidence of an explicit teaching of a motivation to combine in the prior art.

The Supreme Court in KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395-97 (2007) identified a number of rationales to support a conclusion of obviousness which are consistent with the proper “functional approach” to the determination of obviousness as laid down in Graham. The key to supporting any rejection under 35 U.S.C. 103 is the clear articulation of the reason(s) why the claimed invention would have been obvious. The Supreme Court in KSR noted that the analysis supporting a rejection under 35 U.S.C. 103 should be made explicit. In Ball Aerosol v. Ltd. Brands, 555 F.3d 984, 89 USPQ2d 1870 (Fed. Cir. 2009), the Federal Circuit offered additional instruction as to the need for an explicit analysis. The Federal Circuit explained that the Supreme Court’s requirement for an explicit analysis does not require record evidence of an explicit teaching of a motivation to combine in the prior art.

“[T]he analysis that “should be made explicit” refers not to the teachings in the prior art of a motivation to combine, but to the court’s analysis…. Under the flexible inquiry set forth by the Supreme Court, the district court therefore erred by failing to take account of ‘the inferences and creative steps,’ or even routine steps, that an inventor would employ and by failing to find a motivation to combine related pieces from the prior art.” Ball Aerosol, 555 F.3d at 993, 89 USPQ2d at 1877.

Id. at 1301, 84 USPQ2d at 1204. The Aventis court also relied on the settled principle that in chemical cases, structural similarity can provide the necessary reason to modify prior art teachings. The Federal Circuit also addressed the kind of teaching that would be sufficient in the absence of an explicitly stated prior art-based motivation, explaining that an expectation of similar properties in light of the prior art can be sufficient, even without an explicit teaching that the compound will have a particular utility.

Obviousness based on structural similarity thus can be proved by identification of some motivation that would have led one of ordinary skill in the art to select and then modify a known compound (i.e. a lead compound) in a particular way to achieve the claimed compound…. In keeping with the flexible nature of the obviousness inquiry, the requisite motivation can come from any number of sources and need not necessarily be explicit in the art. Rather “it is sufficient to show that the claimed and prior art compounds possess a ‘sufficiently close relationship… to create an expectation,’ in light of the totality of the prior art, that the new compound will have ‘similar properties’ to the old.” Id. at 1357, 87 USPQ2d at 1455. (citations omitted)

The courts have made clear that the teaching, suggestion, or motivation test is flexible and an explicit suggestion to combine the prior art is not necessary. The motivation to combine may be implicit and may be found in the knowledge of one of ordinary skill in the art, or, in some cases, from the nature of the problem to be solved. Id. at 1366, 80 USPQ2d at 1649. “[A]n implicit motivation to combine exists not only when a suggestion may be gleaned from the prior art as a whole, but when the ‘improvement’ is technology-independent and the combination of references results in a product or process that is more desirable, for example because it is stronger, cheaper, cleaner, faster, lighter, smaller, more durable, or more efficient. Because the desire to enhance commercial opportunities by improving a product or process is universal—and even common-sensical—we have held that there exists in these situations a motivation to combine prior art references even absent any hint of suggestion in the references themselves. In such situations, the proper question is whether the ordinary artisan possesses knowledge and skills rendering him capable of combining the prior art references.” Id. at 1368, 80 USPQ2d at 1651.

“[T]he analysis that “should be made explicit” refers not to the teachings in the prior art of a motivation to combine, but to the court’s analysis…. Under the flexible inquiry set forth by the Supreme Court, the district court therefore erred by failing to take account of ‘the inferences and creative steps,’ or even routine steps, that an inventor would employ and by failing to find a motivation to combine related pieces from the prior art.” Ball Aerosol, 555 F.3d at 993, 89 USPQ2d at 1877.

Id. at 1301, 84 USPQ2d at 1204. The Aventis court also relied on the settled principle that in chemical cases, structural similarity can provide the necessary reason to modify prior art teachings. The Federal Circuit also addressed the kind of teaching that would be sufficient in the absence of an explicitly stated prior art-based motivation, explaining that an expectation of similar properties in light of the prior art can be sufficient, even without an explicit teaching that the compound will have a particular utility.

Obviousness based on structural similarity thus can be proved by identification of some motivation that would have led one of ordinary skill in the art to select and then modify a known compound (i.e. a lead compound) in a particular way to achieve the claimed compound…. In keeping with the flexible nature of the obviousness inquiry, the requisite motivation can come from any number of sources and need not necessarily be explicit in the art. Rather “it is sufficient to show that the claimed and prior art compounds possess a ‘sufficiently close relationship… to create an expectation,’ in light of the totality of the prior art, that the new compound will have ‘similar properties’ to the old.” Id. at 1357, 87 USPQ2d at 1455. (citations omitted)

The courts have made clear that the teaching, suggestion, or motivation test is flexible and an explicit suggestion to combine the prior art is not necessary. The motivation to combine may be implicit and may be found in the knowledge of one of ordinary skill in the art, or, in some cases, from the nature of the problem to be solved. Id. at 1366, 80 USPQ2d at 1649. “[A]n implicit motivation to combine exists not only when a suggestion may be gleaned from the prior art as a whole, but when the ‘improvement’ is technology-independent and the combination of references results in a product or process that is more desirable, for example because it is stronger, cheaper, cleaner, faster, lighter, smaller, more durable, or more efficient. Because the desire to enhance commercial opportunities by improving a product or process is universal—and even common-sensical—we have held that there exists in these situations a motivation to combine prior art references even absent any hint of suggestion in the references themselves. In such situations, the proper question is whether the ordinary artisan possesses knowledge and skills rendering him capable of combining the prior art references.” Id. at 1368, 80 USPQ2d at 1651.

The court then turned to the question of whether there would have been adequate motivation to combine the prior art elements as had been urged by Master Lock. The court recalled the Graham inquiries, and also emphasized the “expansive and flexible” post-KSR approach to obviousness that must not “deny factfinders recourse to common sense.” Id. at 1238, 95 USPQ2d at 1530-31. (quoting KSR, 550 U.S. at 415, 421, 82 USPQ2d at 1395, 1397). The court stated:

The Federal Circuit pointed out that application of common sense is not really an innovation in the law of obviousness when it stated, “Common sense has long been recognized to inform the analysis of obviousness if explained with sufficient reasoning.” Perfect Web, 587 F.3d at 1328, 92 USPQ2d at 1853 (emphasis added). The Federal Circuit then provided a review of a number of precedential cases that inform the understanding of common sense, including In re Bozek, 416 F.2d 1385, 1390, 163 USPQ 545, 549 (CCPA 1969) (explaining that a patent examiner may rely on “common knowledge and common sense of the person of ordinary skill in the art without any specific hint or suggestion in a particular reference”) and In re Zurko, 258 F.3d 1379, 1383, 1385, 59 USPQ2d 1693 at 1695, 1697 (Fed. Cir. 2001) (clarifying that a factual foundation is needed in order for an examiner to invoke “good common sense” in a case in which “basic knowledge and common sense was not based on any evidence in the record”). The Federal Circuit implicitly acknowledged in Perfect Web that the kind of strict evidence-based teaching, suggestion, or motivation required in In re Lee, 277 F.3d 1338, 1344, 61 USPQ2d 1430, 1434 (Fed. Cir. 2002), is not an absolute requirement for an obviousness rejection in light of the teachings of KSR. The Federal Circuit explained that “[a]t the time [of the Lee decision], we required the PTO to identify record evidence of a teaching, suggestion, or motivation to combine references.” However, Perfect Web went on to state that even under Lee, common sense could properly be applied when analyzing evidence relevant to obviousness. Citing DyStar Textilfarben GmbH v. C.H. Patrick Co., 464 F.3d 1356, 80 USPQ2d 1641 (Fed. Cir. 2006), and In re Kahn, 441 F.3d 977, 78 USPQ2d 1329 (Fed. Cir. 2006), two cases decided shortly before the Supreme Court’s decision in KSR, the Federal Circuit noted that although “a reasoned explanation that avoids conclusory generalizations” is required to use common sense, identification of a “specific hint or suggestion in a particular reference” is not. See also B/E Aerospace, Inc. v. C&D Zodiac, Inc., 962 F.3d 1373, 1380-81, 2020 USPQ2d 10706 (Fed. Cir. 2020) (stating that “the Board’s invocation of common sense was properly accompanied by reasoned analysis and evidentiary support” to show why it would be obvious to incorporate a second recess to receive an airplane seat support). But see Arendi v. Apple, 832 F.3d 1355, 119 USPQ2d 1822 (Fed. Cir. 2016) (finding that the Board had not provided a reasoned analysis, supported by the evidence of record, for why “common sense” taught the missing process step).

The courts have made clear that the teaching, suggestion, or motivation test is flexible and an explicit suggestion to combine the prior art is not necessary. The motivation to combine may be implicit and may be found in the knowledge of one of ordinary skill in the art, or, in some cases, from the nature of the problem to be solved. Id. at 1366, 80 USPQ2d at 1649. “[A]n implicit motivation to combine exists not only when a suggestion may be gleaned from the prior art as a whole, but when the ‘improvement’ is technology-independent and the combination of references results in a product or process that is more desirable, for example because it is stronger, cheaper, cleaner, faster, lighter, smaller, more durable, or more efficient. Because the desire to enhance commercial opportunities by improving a product or process is universal—and even common-sensical—we have held that there exists in these situations a motivation to combine prior art references even absent any hint of suggestion in the references themselves. In such situations, the proper question is whether the ordinary artisan possesses knowledge and skills rendering him capable of combining the prior art references.” Id. at 1368, 80 USPQ2d at 1651.

The courts have made clear that the teaching, suggestion, or motivation test is flexible and an explicit suggestion to combine the prior art is not necessary. The motivation to combine may be implicit and may be found in the knowledge of one of ordinary skill in the art, or, in some cases, from the nature of the problem to be solved. Id. at 1366, 80 USPQ2d at 1649. “[A]n implicit motivation to combine exists not only when a suggestion may be gleaned from the prior art as a whole, but when the ‘improvement’ is technology-independent and the combination of references results in a product or process that is more desirable, for example because it is stronger, cheaper, cleaner, faster, lighter, smaller, more durable, or more efficient. Because the desire to enhance commercial opportunities by improving a product or process is universal—and even common-sensical—we have held that there exists in these situations a motivation to combine prior art references even absent any hint of suggestion in the references themselves. In such situations, the proper question is whether the ordinary artisan possesses knowledge and skills rendering him capable of combining the prior art references.” Id. at 1368, 80 USPQ2d at 1651.

[Editor Note: This MPEP section is applicable regardless of whether an application is examined under the AIA or under pre-AIA law. For applications subject to the first inventor to file (FITF) provisions of the AIA, the relevant time is "before the effective filing date of the claimed invention". For applications subject to pre-AIA 35 U.S.C. 102, the relevant time is "at the time of the invention". See MPEP § 2150 et seq. Many of the court decisions discussed in this section involved applications or patents subject to pre-AIA 35 U.S.C. 102. These court decisions may be applicable to applications and patents subject to AIA 35 U.S.C. 102 but the relevant time is before the effective filing date of the claimed invention and not at the time of the invention.]

[Editor Note: This MPEP section is applicable regardless of whether an application is examined under the AIA or under pre-AIA law. For applications subject to the first inventor to file (FITF) provisions of the AIA, the relevant time is "before the effective filing date of the claimed invention". For applications subject to pre-AIA 35 U.S.C. 102, the relevant time is "at the time of the invention". See MPEP § 2150 et seq. Many of the court decisions discussed in this section involved applications or patents subject to pre-AIA 35 U.S.C. 102. These court decisions may be applicable to applications and patents subject to AIA 35 U.S.C. 102 but the relevant time is before the effective filing date of the claimed invention and not at the time of the invention.]

[Editor Note: This MPEP section is applicable regardless of whether an application is examined under the AIA or under pre-AIA law. For applications subject to the first inventor to file (FITF) provisions of the AIA, the relevant time is "before the effective filing date of the claimed invention". For applications subject to pre-AIA 35 U.S.C. 102, the relevant time is "at the time of the invention". See MPEP § 2150 et seq. Many of the court decisions discussed in this section involved applications or patents subject to pre-AIA 35 U.S.C. 102. These court decisions may be applicable to applications and patents subject to AIA 35 U.S.C. 102 but the relevant time is before the effective filing date of the claimed invention and not at the time of the invention.]

The Supreme Court in KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395-97 (2007) identified a number of rationales to support a conclusion of obviousness which are consistent with the proper “functional approach” to the determination of obviousness as laid down in Graham. The key to supporting any rejection under 35 U.S.C. 103 is the clear articulation of the reason(s) why the claimed invention would have been obvious. The Supreme Court in KSR noted that the analysis supporting a rejection under 35 U.S.C. 103 should be made explicit. In Ball Aerosol v. Ltd. Brands, 555 F.3d 984, 89 USPQ2d 1870 (Fed. Cir. 2009), the Federal Circuit offered additional instruction as to the need for an explicit analysis. The Federal Circuit explained that the Supreme Court’s requirement for an explicit analysis does not require record evidence of an explicit teaching of a motivation to combine in the prior art.

To reject a claim based on this rationale, Office personnel must resolve the Graham factual inquiries. Then, Office personnel must articulate the following (1) a finding that the prior art contained a “base” device (method, or product) upon which the claimed invention can be seen as an “improvement;”

To reject a claim based on this rationale, Office personnel must resolve the Graham factual inquiries. Then, Office personnel must articulate the following (1) a finding that the prior art contained a “base” device (method, or product) upon which the claimed invention can be seen as an “improvement;”

[Editor Note: This MPEP section is applicable regardless of whether an application is examined under the AIA or under pre-AIA law. For applications subject to the first inventor to file (FITF) provisions of the AIA, the relevant time is "before the effective filing date of the claimed invention". For applications subject to pre-AIA 35 U.S.C. 102, the relevant time is "at the time of the invention". See MPEP § 2150 et seq. Many of the court decisions discussed in this section involved applications or patents subject to pre-AIA 35 U.S.C. 102. These court decisions may be applicable to applications and patents subject to AIA 35 U.S.C. 102 but the relevant time is before the effective filing date of the claimed invention and not at the time of the invention.]

[Editor Note: This MPEP section is applicable regardless of whether an application is examined under the AIA or under pre-AIA law. For applications subject to the first inventor to file (FITF) provisions of the AIA, the relevant time is "before the effective filing date of the claimed invention". For applications subject to pre-AIA 35 U.S.C. 102, the relevant time is "at the time of the invention". See MPEP § 2150 et seq. Many of the court decisions discussed in this section involved applications or patents subject to pre-AIA 35 U.S.C. 102. These court decisions may be applicable to applications and patents subject to AIA 35 U.S.C. 102 but the relevant time is before the effective filing date of the claimed invention and not at the time of the invention.]

The Supreme Court in KSR Int'l Co. v. Teleflex Inc., 550 U.S. 398, 415-421, 82 USPQ2d 1385, 1395-97 (2007) identified a number of rationales to support a conclusion of obviousness which are consistent with the proper “functional approach” to the determination of obviousness as laid down in Graham. The key to supporting any rejection under 35 U.S.C. 103 is the clear articulation of the reason(s) why the claimed invention would have been obvious. The Supreme Court in KSR noted that the analysis supporting a rejection under 35 U.S.C. 103 should be made explicit. In Ball Aerosol v. Ltd. Brands, 555 F.3d 984, 89 USPQ2d 1870 (Fed. Cir. 2009), the Federal Circuit offered additional instruction as to the need for an explicit analysis. The Federal Circuit explained that the Supreme Court’s requirement for an explicit analysis does not require record evidence of an explicit teaching of a motivation to combine in the prior art.

The court then turned to the question of whether there would have been adequate motivation to combine the prior art elements as had been urged by Master Lock. The court recalled the Graham inquiries, and also emphasized the “expansive and flexible” post-KSR approach to obviousness that must not “deny factfinders recourse to common sense.” Id. at 1238, 95 USPQ2d at 1530-31. (quoting KSR, 550 U.S. at 415, 421, 82 USPQ2d at 1395, 1397). The court stated:

ICON is another useful example for understanding the scope of analogous art. The art applied concerned retaining mechanisms for folding beds, not treadmills. When determining whether a reference may properly be applied to an invention in a different field of endeavor, it is necessary to consider the problem to be solved. It is certainly possible that a reference may be drawn in such a way that its usefulness as a teaching is narrowly restricted. However, in ICON, the problem to be solved was not limited to the teaching of the “treadmill” concept. The Teague reference was analogous art because “Teague and the current application both address the need to stably retain a folding mechanism,” and because “nothing about ICON’s folding mechanism requires any particular focus on treadmills,” Id. at 1378, 1380, 83 USPQ2d at 1749-50.

ICON is another useful example for understanding the scope of analogous art. The art applied concerned retaining mechanisms for folding beds, not treadmills. When determining whether a reference may properly be applied to an invention in a different field of endeavor, it is necessary to consider the problem to be solved. It is certainly possible that a reference may be drawn in such a way that its usefulness as a teaching is narrowly restricted. However, in ICON, the problem to be solved was not limited to the teaching of the “treadmill” concept. The Teague reference was analogous art because “Teague and the current application both address the need to stably retain a folding mechanism,” and because “nothing about ICON’s folding mechanism requires any particular focus on treadmills,” Id. at 1378, 1380, 83 USPQ2d at 1749-50.

ICON is another useful example for understanding the scope of analogous art. The art applied concerned retaining mechanisms for folding beds, not treadmills. When determining whether a reference may properly be applied to an invention in a different field of endeavor, it is necessary to consider the problem to be solved. It is certainly possible that a reference may be drawn in such a way that its usefulness as a teaching is narrowly restricted. However, in ICON, the problem to be solved was not limited to the teaching of the “treadmill” concept. The Teague reference was analogous art because “Teague and the current application both address the need to stably retain a folding mechanism,” and because “nothing about ICON’s folding mechanism requires any particular focus on treadmills,” Id. at 1378, 1380, 83 USPQ2d at 1749-50.

The Court stated that “[t]he proper question to have asked was whether a pedal designer of ordinary skill, facing the wide range of needs created by developments in the field of endeavor, would have seen a benefit to upgrading Asano with a sensor.” Id. at 424, 82 USPQ2d at 1399. The Court found that technological developments in the automotive design would have prompted a designer to upgrade Asano with an electronic sensor. The next question was where to attach the sensor. Based on the prior art, a designer would have known to place the sensor on a nonmoving part of the pedal structure and the most obvious nonmoving point on the structure from which a sensor can easily detect the pedal’s position was a pivot point. The Court concluded that it would have been obvious to upgrade Asano’s fixed pivot point adjustable pedal by replacing the mechanical assembly for throttle control with an electronic throttle control and to mount the electronic sensor on the pedal support structure.

The claimed invention in In re Urbanski, 809 F.3d 1237, 1244, 117 USPQ2d 1499, 1504 (Fed. Cir. 2016) was directed to a method of enzymatic hydrolysis of soy fiber to reduce water holding capacity, requiring reacting the soy fiber and enzyme in water for about 60-120 minutes. The claims were rejected over two references, wherein the primary reference, Gross, taught using a reaction time of 5 to 72 hours and the secondary reference, Wong, taught using a reaction time of 100 to 240 minutes, preferably 120 minutes. The applicant argued that modifying the primary reference in the manner suggested by the secondary reference would forego the benefits taught by the primary reference, thereby teaching away from the combination. The court found there was sufficient motivation to combine because both references recognized reaction time and degree of hydrolysis as result-effective variables, which can be varied to have a predictable effect on the final product; and the primary reference does not contain an express teaching away from the proposed modification. “Substantial evidence thus supports the Board’s finding that a person of ordinary skill would have been motivated to modify the Gross process by using a shorter reaction time, in order to obtain the favorable properties disclosed in Wong.”

Relying on In re Deuel, 51 F.3d 1552, 34 USPQ2d 1210 (Fed. Cir. 1995), appellant argued that it was improper for the Office to use the polypeptide of the Valiante patent together with the methods described in Sambrook to reject a claim drawn to a specific nucleic acid molecule without providing a reference showing or suggesting a structurally similar nucleic acid molecule. Citing KSR, the Board stated that “when there is motivation to solve a problem and there are a finite number of identified, predictable solutions, a person of ordinary skill has good reason to pursue the known options within his or her technical grasp. If this leads to anticipated success, it is likely the product not of innovation but of ordinary skill and common sense.” KSR, 550 U.S. at 402-03, 82 USPQ2d at 1390. The Board noted that the problem facing those in the art was to isolate a specific nucleic acid, and there were a limited number of methods available to do so. The Board concluded that the skilled artisan would have had reason to try these methods with the reasonable expectation that at least one would be successful. Thus, isolating the specific nucleic acid molecule claimed was “the product not of innovation but of ordinary skill and common sense.” Id.

The Omeprazole case can also be analyzed in view of the discovery of a previously unknown problem by the patentee. If the adverse interaction between active agent and coating had been known, it might well have been obvious to use a subcoating. However, since the problem had not been previously known, there would have been no reason to incur additional time and expense to add another layer, even though the addition would have been technologically possible. This is true because the prior art of record failed to mention any stability problem, despite the acknowledgment during testimony at trial that there was a known theoretical reason that omeprazole might be subject to degradation in the presence of the known coating material.

If optimization of the application parameters had not been within the level of ordinary skill in the art, the outcome of the Ecolab case may well have been different.

The claimed invention in In re Fout, 675 F.2d 297, 213 USPQ 532 (CCPA 1982) was directed to a method for decaffeinating coffee or tea. The prior art (Pagliaro) method produced a decaffeinated vegetable material and trapped the caffeine in a fatty material (such as oil). The caffeine was then removed from the fatty material by an aqueous extraction process. Applicant (Fout) substituted an evaporative distillation step for the aqueous extraction step. The prior art (Waterman) suspended coffee in oil and then directly distilled the caffeine through the oil. The court found that “[b]ecause both Pagliaro and Waterman teach a method for separating caffeine from oil, it would have been prima facie obvious to substitute one method for the other. Express suggestion to substitute one equivalent for another need not be present to render such substitution obvious.” Id. at 301, 213 USPQ at 536.

The rationale to support a conclusion that the claim would have been obvious is that a method of enhancing a particular class of devices (methods, or products) has been made part of the ordinary capabilities of one skilled in the art based upon the teaching of such improvement in other situations. One of ordinary skill in the art would have been capable of applying this known method of enhancement to a “base” device (method, or product) in the prior art and the results would have been predictable to one of ordinary skill in the art. “It's enough … to show that there was a known problem … in the art, that [another reference] … helped address that issue, and that combining the teachings of [the two references] wasn't beyond the skill of an ordinary artisan. Nothing more is required to show a motivation to combine under KSR. ” See Intel Corp. v. PACT XPP Schweiz AG, 61 F.4th 1373, 1380-81, 2023 USPQ2d 297 (Fed. Cir. 2023) (finding that both prior art references “address the same problem and that [the secondary reference’s] cache was a known way to address that problem is precisely the reason that there's a motivation to combine under KSR and our precedent.”).

The claimed invention in In re Urbanski, 809 F.3d 1237, 1244, 117 USPQ2d 1499, 1504 (Fed. Cir. 2016) was directed to a method of enzymatic hydrolysis of soy fiber to reduce water holding capacity, requiring reacting the soy fiber and enzyme in water for about 60-120 minutes. The claims were rejected over two references, wherein the primary reference, Gross, taught using a reaction time of 5 to 72 hours and the secondary reference, Wong, taught using a reaction time of 100 to 240 minutes, preferably 120 minutes. The applicant argued that modifying the primary reference in the manner suggested by the secondary reference would forego the benefits taught by the primary reference, thereby teaching away from the combination. The court found there was sufficient motivation to combine because both references recognized reaction time and degree of hydrolysis as result-effective variables, which can be varied to have a predictable effect on the final product; and the primary reference does not contain an express teaching away from the proposed modification. “Substantial evidence thus supports the Board’s finding that a person of ordinary skill would have been motivated to modify the Gross process by using a shorter reaction time, in order to obtain the favorable properties disclosed in Wong.”

The Federal Circuit’s decision in In re Kubin, 561 F.3d 1351, 90 USPQ2d 1417 (Fed. Cir. 2009), affirmed the Office’s determination in Ex parte Kubin, 83 USPQ2d 1410 (Bd. Pat. App. & Int. 2007) that the claims in question, directed to an isolated nucleic acid molecule, would have been obvious over the prior art applied. The claim stated that the nucleic acid encoded a particular polypeptide. The encoded polypeptide was identified in the claim by its partially specified sequence, and by its ability to bind to a specified protein.