MPEP § 716.02(a) — Evidence Must Show Unexpected Results (Annotated Rules)

§716.02(a) Evidence Must Show Unexpected Results

USPTO MPEP version: BlueIron's Update: 2025-12-31

This page consolidates and annotates all enforceable requirements under MPEP § 716.02(a), including statutory authority, regulatory rules, examiner guidance, and practice notes. It is provided as guidance, with links to the ground truth sources. This is information only, it is not legal advice.

Evidence Must Show Unexpected Results

This section addresses Evidence Must Show Unexpected Results. Primary authority: 35 U.S.C. 103. Contains: 2 requirements, 4 permissions, and 5 other statements.

Key Rules

Topic

Establishing Prima Facie Case

5 rules
MPEP GuidanceInformativeAlways
[mpep-716-02-a-5fa18f504b8c74ca1d9e70e2]
Requirement for Showing Greater Than Expected Result
Note:
The rule requires showing that the claimed combination produces a result greater than expected, even if equal to one component alone, to establish nonobviousness.

“A greater than expected result is an evidentiary factor pertinent to the legal conclusion of obviousness… of the claims at issue.” In re Corkill, 771 F.2d 1496, 226 USPQ 1005 (Fed. Cir. 1985). In Corkhill, the claimed combination showed an additive result when a diminished result would have been expected. This result was persuasive of nonobviousness even though the result was equal to that of one component alone. Evidence of a greater than expected result may also be shown by demonstrating an effect which is greater than the sum of each of the effects taken separately (i.e., demonstrating “synergism”). Merck & Co. Inc. v. Biocraft Laboratories Inc., 874 F.2d 804, 10 USPQ2d 1843 (Fed. Cir.), cert. denied, 493 U.S. 975 (1989). However, a greater than additive effect is not necessarily sufficient to overcome a prima facie case of obviousness because such an effect can either be expected or unexpected. Applicants must further show that the results were greater than those which would have been expected from the prior art to an unobvious extent, and that the results are of a significant, practical advantage. Ex parte The NutraSweet Co., 19 USPQ2d 1586 (Bd. Pat. App. & Inter. 1991) (Evidence showing greater than additive sweetness resulting from the claimed mixture of saccharin and L-aspartyl-L-phenylalanine was not sufficient to outweigh the evidence of obviousness because the teachings of the prior art lead to a general expectation of greater than additive sweetening effects when using mixtures of synthetic sweeteners.).

Jump to MPEP SourceEstablishing Prima Facie CaseRebutting Prima Facie CasePrima Facie Case of Obviousness
MPEP GuidancePermittedAlways
[mpep-716-02-a-786f874446753c2b0317ef13]
Requirement for Demonstrating Greater Than Additive Effect
Note:
The rule requires showing that the combined effect of components exceeds their individual effects, proving a significant and unexpected result.

“A greater than expected result is an evidentiary factor pertinent to the legal conclusion of obviousness… of the claims at issue.” In re Corkill, 771 F.2d 1496, 226 USPQ 1005 (Fed. Cir. 1985). In Corkhill, the claimed combination showed an additive result when a diminished result would have been expected. This result was persuasive of nonobviousness even though the result was equal to that of one component alone. Evidence of a greater than expected result may also be shown by demonstrating an effect which is greater than the sum of each of the effects taken separately (i.e., demonstrating “synergism”). Merck & Co. Inc. v. Biocraft Laboratories Inc., 874 F.2d 804, 10 USPQ2d 1843 (Fed. Cir.), cert. denied, 493 U.S. 975 (1989). However, a greater than additive effect is not necessarily sufficient to overcome a prima facie case of obviousness because such an effect can either be expected or unexpected. Applicants must further show that the results were greater than those which would have been expected from the prior art to an unobvious extent, and that the results are of a significant, practical advantage. Ex parte The NutraSweet Co., 19 USPQ2d 1586 (Bd. Pat. App. & Inter. 1991) (Evidence showing greater than additive sweetness resulting from the claimed mixture of saccharin and L-aspartyl-L-phenylalanine was not sufficient to outweigh the evidence of obviousness because the teachings of the prior art lead to a general expectation of greater than additive sweetening effects when using mixtures of synthetic sweeteners.).

Jump to MPEP SourceEstablishing Prima Facie CaseRebutting Prima Facie CasePrima Facie Case of Obviousness
MPEP GuidancePermittedAlways
[mpep-716-02-a-b9e9ebcb6d15b9f9b5c5d4a7]
Greater Than Additive Effect Not Sufficient for Nonobviousness
Note:
A greater than expected result is not enough to prove nonobviousness if the effect can be expected or unexpected. Applicants must show significant, practical advantages beyond what would be expected from prior art.

“A greater than expected result is an evidentiary factor pertinent to the legal conclusion of obviousness… of the claims at issue.” In re Corkill, 771 F.2d 1496, 226 USPQ 1005 (Fed. Cir. 1985). In Corkhill, the claimed combination showed an additive result when a diminished result would have been expected. This result was persuasive of nonobviousness even though the result was equal to that of one component alone. Evidence of a greater than expected result may also be shown by demonstrating an effect which is greater than the sum of each of the effects taken separately (i.e., demonstrating “synergism”). Merck & Co. Inc. v. Biocraft Laboratories Inc., 874 F.2d 804, 10 USPQ2d 1843 (Fed. Cir.), cert. denied, 493 U.S. 975 (1989). However, a greater than additive effect is not necessarily sufficient to overcome a prima facie case of obviousness because such an effect can either be expected or unexpected. Applicants must further show that the results were greater than those which would have been expected from the prior art to an unobvious extent, and that the results are of a significant, practical advantage. Ex parte The NutraSweet Co., 19 USPQ2d 1586 (Bd. Pat. App. & Inter. 1991) (Evidence showing greater than additive sweetness resulting from the claimed mixture of saccharin and L-aspartyl-L-phenylalanine was not sufficient to outweigh the evidence of obviousness because the teachings of the prior art lead to a general expectation of greater than additive sweetening effects when using mixtures of synthetic sweeteners.).

Jump to MPEP SourceEstablishing Prima Facie CaseRebutting Prima Facie CasePrima Facie Case of Obviousness
MPEP GuidanceRequiredAlways
[mpep-716-02-a-85c0233bfb420b24c971e5b6]
Results Must Be Greater Than Expected and Practical
Note:
Applicants must demonstrate that the results of their invention are significantly better than what would be expected from prior art and offer a practical advantage.

“A greater than expected result is an evidentiary factor pertinent to the legal conclusion of obviousness… of the claims at issue.” In re Corkill, 771 F.2d 1496, 226 USPQ 1005 (Fed. Cir. 1985). In Corkhill, the claimed combination showed an additive result when a diminished result would have been expected. This result was persuasive of nonobviousness even though the result was equal to that of one component alone. Evidence of a greater than expected result may also be shown by demonstrating an effect which is greater than the sum of each of the effects taken separately (i.e., demonstrating “synergism”). Merck & Co. Inc. v. Biocraft Laboratories Inc., 874 F.2d 804, 10 USPQ2d 1843 (Fed. Cir.), cert. denied, 493 U.S. 975 (1989). However, a greater than additive effect is not necessarily sufficient to overcome a prima facie case of obviousness because such an effect can either be expected or unexpected. Applicants must further show that the results were greater than those which would have been expected from the prior art to an unobvious extent, and that the results are of a significant, practical advantage. Ex parte The NutraSweet Co., 19 USPQ2d 1586 (Bd. Pat. App. & Inter. 1991) (Evidence showing greater than additive sweetness resulting from the claimed mixture of saccharin and L-aspartyl-L-phenylalanine was not sufficient to outweigh the evidence of obviousness because the teachings of the prior art lead to a general expectation of greater than additive sweetening effects when using mixtures of synthetic sweeteners.).

Jump to MPEP SourceEstablishing Prima Facie CaseRebutting Prima Facie CasePrima Facie Case of Obviousness
MPEP GuidanceInformativeAlways
[mpep-716-02-a-4f302bbf6f9ebe928b645db3]
Evidence Must Show Greater Than Expected Results to Overcome Obviousness
Note:
The rule requires that evidence demonstrating a greater than expected result be shown to overcome a prima facie case of obviousness, and must show the results are significant and practical.

“A greater than expected result is an evidentiary factor pertinent to the legal conclusion of obviousness… of the claims at issue.” In re Corkill, 771 F.2d 1496, 226 USPQ 1005 (Fed. Cir. 1985). In Corkhill, the claimed combination showed an additive result when a diminished result would have been expected. This result was persuasive of nonobviousness even though the result was equal to that of one component alone. Evidence of a greater than expected result may also be shown by demonstrating an effect which is greater than the sum of each of the effects taken separately (i.e., demonstrating “synergism”). Merck & Co. Inc. v. Biocraft Laboratories Inc., 874 F.2d 804, 10 USPQ2d 1843 (Fed. Cir.), cert. denied, 493 U.S. 975 (1989). However, a greater than additive effect is not necessarily sufficient to overcome a prima facie case of obviousness because such an effect can either be expected or unexpected. Applicants must further show that the results were greater than those which would have been expected from the prior art to an unobvious extent, and that the results are of a significant, practical advantage. Ex parte The NutraSweet Co., 19 USPQ2d 1586 (Bd. Pat. App. & Inter. 1991) (Evidence showing greater than additive sweetness resulting from the claimed mixture of saccharin and L-aspartyl-L-phenylalanine was not sufficient to outweigh the evidence of obviousness because the teachings of the prior art lead to a general expectation of greater than additive sweetening effects when using mixtures of synthetic sweeteners.).

Jump to MPEP SourceEstablishing Prima Facie CaseRebutting Prima Facie CasePrima Facie Case of Obviousness
Topic

Establishing Prima Facie Case

3 rules
StatutoryPermittedAlways
[mpep-716-02-a-cc56511c674d222a3eab4e66]
Evidence of Superior Properties Can Overcome Obviousness
Note:
Evidence showing a compound has unexpected superior properties, even in shared characteristics with prior art, can rebut a prima facie case of obviousness.

Evidence of unobvious or unexpected advantageous properties, such as superiority in a property the claimed compound shares with the prior art, can rebut prima facie obviousness. “Evidence that a compound is unexpectedly superior in one of a spectrum of common properties… can be enough to rebut a prima facie case of obviousness.” No set number of examples of superiority is required. In re Chupp, 816 F.2d 643, 646, 2 USPQ2d 1437, 1439 (Fed. Cir. 1987) (Evidence showing that the claimed herbicidal compound was more effective than the closest prior art compound in controlling quackgrass and yellow nutsedge weeds in corn and soybean crops was sufficient to overcome the rejection under 35 U.S.C. 103, even though the specification indicated the claimed compound was an average performer on crops other than corn and soybean.). See also Ex parte A, 17 USPQ2d 1716 (Bd. Pat. App. & Inter. 1990) (unexpected superior therapeutic activity of claimed compound against anaerobic bacteria was sufficient to rebut prima facie obviousness even though there was no evidence that the compound was effective against all bacteria).

Jump to MPEP SourceEstablishing Prima Facie CaseClaim Patentability AnalysisComposition of Matter Claims
StatutoryPermittedAlways
[mpep-716-02-a-b1b1dab0608df6ca8196f391]
Evidence of Unexpected Superior Property Can Rebut Obviousness
Note:
Evidence showing a compound is unexpectedly superior in a common property can overcome a prima facie case of obviousness.

Evidence of unobvious or unexpected advantageous properties, such as superiority in a property the claimed compound shares with the prior art, can rebut prima facie obviousness. “Evidence that a compound is unexpectedly superior in one of a spectrum of common properties… can be enough to rebut a prima facie case of obviousness.” No set number of examples of superiority is required. In re Chupp, 816 F.2d 643, 646, 2 USPQ2d 1437, 1439 (Fed. Cir. 1987) (Evidence showing that the claimed herbicidal compound was more effective than the closest prior art compound in controlling quackgrass and yellow nutsedge weeds in corn and soybean crops was sufficient to overcome the rejection under 35 U.S.C. 103, even though the specification indicated the claimed compound was an average performer on crops other than corn and soybean.). See also Ex parte A, 17 USPQ2d 1716 (Bd. Pat. App. & Inter. 1990) (unexpected superior therapeutic activity of claimed compound against anaerobic bacteria was sufficient to rebut prima facie obviousness even though there was no evidence that the compound was effective against all bacteria).

Jump to MPEP SourceEstablishing Prima Facie CaseClaim Patentability AnalysisComposition of Matter Claims
StatutoryRequiredAlways
[mpep-716-02-a-2b68f8f053827ce2649308ab]
Requirement for Showing Unexpected Superiority to Prior Art
Note:
The rule requires that evidence of unexpected superiority over prior art compounds can rebut a prima facie case of obviousness, regardless of average performance in other areas.

Evidence of unobvious or unexpected advantageous properties, such as superiority in a property the claimed compound shares with the prior art, can rebut prima facie obviousness. “Evidence that a compound is unexpectedly superior in one of a spectrum of common properties… can be enough to rebut a prima facie case of obviousness.” No set number of examples of superiority is required. In re Chupp, 816 F.2d 643, 646, 2 USPQ2d 1437, 1439 (Fed. Cir. 1987) (Evidence showing that the claimed herbicidal compound was more effective than the closest prior art compound in controlling quackgrass and yellow nutsedge weeds in corn and soybean crops was sufficient to overcome the rejection under 35 U.S.C. 103, even though the specification indicated the claimed compound was an average performer on crops other than corn and soybean.). See also Ex parte A, 17 USPQ2d 1716 (Bd. Pat. App. & Inter. 1990) (unexpected superior therapeutic activity of claimed compound against anaerobic bacteria was sufficient to rebut prima facie obviousness even though there was no evidence that the compound was effective against all bacteria).

Jump to MPEP SourceEstablishing Prima Facie CaseClaim Patentability AnalysisComposition of Matter Claims
Topic

Obviousness of Ranges and Values

2 rules
StatutoryInformativeAlways
[mpep-716-02-a-e8595574d57724a91de8c54d]
Evidence of Nonobviousness Through Unexpected Properties
Note:
The presence of a property not found in prior art is evidence that the invention is nonobvious.

Presence of a property not possessed by the prior art is evidence of nonobviousness. In re Papesch, 315 F.2d 381, 137 USPQ 43 (CCPA 1963) (rejection of claims to compound structurally similar to the prior art compound was reversed because claimed compound unexpectedly possessed anti-inflammatory properties not possessed by the prior art compound); Ex parte Thumm, 132 USPQ 66 (Bd. App. 1961) (Appellant showed that the claimed range of ethylene diamine was effective for the purpose of producing “‘regenerated cellulose consisting substantially entirely of skin’” whereas the prior art warned “this compound has ‘practically no effect.’ ”). The submission of evidence that a new product possesses unexpected properties does not necessarily require a conclusion that the claimed invention is nonobvious. In re Payne, 606 F.2d 303, 203 USPQ 245 (CCPA 1979). See the discussion of latent properties and additional advantages in MPEP § 2145.

Jump to MPEP SourceObviousness of Ranges and ValuesObviousnessEx Parte Appeals to PTAB
StatutoryInformativeAlways
[mpep-716-02-a-4d138664a02a3f6089c4a5ab]
Unexpected Properties Show Nonobviousness
Note:
Evidence that a new product possesses unexpected properties can show the invention is nonobvious.

Presence of a property not possessed by the prior art is evidence of nonobviousness. In re Papesch, 315 F.2d 381, 137 USPQ 43 (CCPA 1963) (rejection of claims to compound structurally similar to the prior art compound was reversed because claimed compound unexpectedly possessed anti-inflammatory properties not possessed by the prior art compound); Ex parte Thumm, 132 USPQ 66 (Bd. App. 1961) (Appellant showed that the claimed range of ethylene diamine was effective for the purpose of producing “‘regenerated cellulose consisting substantially entirely of skin’” whereas the prior art warned “this compound has ‘practically no effect.’ ”). The submission of evidence that a new product possesses unexpected properties does not necessarily require a conclusion that the claimed invention is nonobvious. In re Payne, 606 F.2d 303, 203 USPQ 245 (CCPA 1979). See the discussion of latent properties and additional advantages in MPEP § 2145.

Jump to MPEP SourceObviousness of Ranges and ValuesObviousnessEx Parte Appeals to PTAB
Topic

35 U.S.C. 103 – Obviousness

2 rules
StatutoryInformativeAlways
[mpep-716-02-a-43595f40a2ef11f130ba05cd]
Unexpected Properties Do Not Necessarily Prove Nonobviousness
Note:
The submission of evidence showing a new product has unexpected properties does not automatically conclude the claimed invention is nonobvious.

Presence of a property not possessed by the prior art is evidence of nonobviousness. In re Papesch, 315 F.2d 381, 137 USPQ 43 (CCPA 1963) (rejection of claims to compound structurally similar to the prior art compound was reversed because claimed compound unexpectedly possessed anti-inflammatory properties not possessed by the prior art compound); Ex parte Thumm, 132 USPQ 66 (Bd. App. 1961) (Appellant showed that the claimed range of ethylene diamine was effective for the purpose of producing “‘regenerated cellulose consisting substantially entirely of skin’” whereas the prior art warned “this compound has ‘practically no effect.’ ”). The submission of evidence that a new product possesses unexpected properties does not necessarily require a conclusion that the claimed invention is nonobvious. In re Payne, 606 F.2d 303, 203 USPQ 245 (CCPA 1979). See the discussion of latent properties and additional advantages in MPEP § 2145.

Jump to MPEP SourceObviousnessObviousness of Ranges and ValuesEx Parte Appeals to PTAB
MPEP GuidanceInformativeAlways
[mpep-716-02-a-1324eeeda45c3b4ad4d69b74]
Evidence of Greater Than Expected Result Supports Nonobviousness
Note:
This evidence shows that a combination resulted in an effect equal to one component alone, supporting the nonobviousness of the claims despite expectations.

“A greater than expected result is an evidentiary factor pertinent to the legal conclusion of obviousness… of the claims at issue.” In re Corkill, 771 F.2d 1496, 226 USPQ 1005 (Fed. Cir. 1985). In Corkhill, the claimed combination showed an additive result when a diminished result would have been expected. This result was persuasive of nonobviousness even though the result was equal to that of one component alone. Evidence of a greater than expected result may also be shown by demonstrating an effect which is greater than the sum of each of the effects taken separately (i.e., demonstrating “synergism”). Merck & Co. Inc. v. Biocraft Laboratories Inc., 874 F.2d 804, 10 USPQ2d 1843 (Fed. Cir.), cert. denied, 493 U.S. 975 (1989). However, a greater than additive effect is not necessarily sufficient to overcome a prima facie case of obviousness because such an effect can either be expected or unexpected. Applicants must further show that the results were greater than those which would have been expected from the prior art to an unobvious extent, and that the results are of a significant, practical advantage. Ex parte The NutraSweet Co., 19 USPQ2d 1586 (Bd. Pat. App. & Inter. 1991) (Evidence showing greater than additive sweetness resulting from the claimed mixture of saccharin and L-aspartyl-L-phenylalanine was not sufficient to outweigh the evidence of obviousness because the teachings of the prior art lead to a general expectation of greater than additive sweetening effects when using mixtures of synthetic sweeteners.).

Jump to MPEP SourceObviousnessEstablishing Prima Facie CaseRebutting Prima Facie Case
Topic

Obviousness

2 rules
MPEP GuidanceInformativeAlways
[mpep-716-02-a-4b995777793e4e67876ba5ae]
Evidence of Greater Than Expected Result Pertains to Obviousness
Note:
The presence of a greater than expected result is considered evidence that may support the conclusion of nonobviousness for claims at issue, even if the result equals or exceeds one component alone.

“A greater than expected result is an evidentiary factor pertinent to the legal conclusion of obviousness… of the claims at issue.” In re Corkill, 771 F.2d 1496, 226 USPQ 1005 (Fed. Cir. 1985). In Corkhill, the claimed combination showed an additive result when a diminished result would have been expected. This result was persuasive of nonobviousness even though the result was equal to that of one component alone. Evidence of a greater than expected result may also be shown by demonstrating an effect which is greater than the sum of each of the effects taken separately (i.e., demonstrating “synergism”). Merck & Co. Inc. v. Biocraft Laboratories Inc., 874 F.2d 804, 10 USPQ2d 1843 (Fed. Cir.), cert. denied, 493 U.S. 975 (1989). However, a greater than additive effect is not necessarily sufficient to overcome a prima facie case of obviousness because such an effect can either be expected or unexpected. Applicants must further show that the results were greater than those which would have been expected from the prior art to an unobvious extent, and that the results are of a significant, practical advantage. Ex parte The NutraSweet Co., 19 USPQ2d 1586 (Bd. Pat. App. & Inter. 1991) (Evidence showing greater than additive sweetness resulting from the claimed mixture of saccharin and L-aspartyl-L-phenylalanine was not sufficient to outweigh the evidence of obviousness because the teachings of the prior art lead to a general expectation of greater than additive sweetening effects when using mixtures of synthetic sweeteners.).

Jump to MPEP SourceObviousnessEstablishing Prima Facie Case
MPEP GuidanceInformativeAlways
[mpep-716-02-a-cb6924433b4875b1c588e58c]
Evidence of Greater Than Additive Sweetening Not Sufficient Without Unexpected Results
Note:
The evidence showing greater than additive sweetness from saccharin and L-aspartyl-L-phenylalanine mixtures is not enough to prove nonobviousness if the prior art suggests a general expectation of such effects.

“A greater than expected result is an evidentiary factor pertinent to the legal conclusion of obviousness… of the claims at issue.” In re Corkill, 771 F.2d 1496, 226 USPQ 1005 (Fed. Cir. 1985). In Corkhill, the claimed combination showed an additive result when a diminished result would have been expected. This result was persuasive of nonobviousness even though the result was equal to that of one component alone. Evidence of a greater than expected result may also be shown by demonstrating an effect which is greater than the sum of each of the effects taken separately (i.e., demonstrating “synergism”). Merck & Co. Inc. v. Biocraft Laboratories Inc., 874 F.2d 804, 10 USPQ2d 1843 (Fed. Cir.), cert. denied, 493 U.S. 975 (1989). However, a greater than additive effect is not necessarily sufficient to overcome a prima facie case of obviousness because such an effect can either be expected or unexpected. Applicants must further show that the results were greater than those which would have been expected from the prior art to an unobvious extent, and that the results are of a significant, practical advantage. Ex parte The NutraSweet Co., 19 USPQ2d 1586 (Bd. Pat. App. & Inter. 1991) (Evidence showing greater than additive sweetness resulting from the claimed mixture of saccharin and L-aspartyl-L-phenylalanine was not sufficient to outweigh the evidence of obviousness because the teachings of the prior art lead to a general expectation of greater than additive sweetening effects when using mixtures of synthetic sweeteners.).

Jump to MPEP SourceObviousnessEstablishing Prima Facie Case
Topic

Unexpected Results

1 rules
StatutoryInformativeAlways
[mpep-716-02-a-fb4b3ba483fb73f4cab9180c]
Evidence of Unexpected Lack of Expected Property Establishes Unobviousness
Note:
The absence of a property that the claimed invention was expected to have based on prior art teachings is evidence of unobviousness.

Absence of property which a claimed invention would have been expected to possess based on the teachings of the prior art is evidence of unobviousness. Ex parte Mead Johnson & Co., 227 USPQ 78 (Bd. Pat. App. & Inter. 1985) (Based on prior art disclosures, claimed compounds would have been expected to possess beta-andrenergic blocking activity; the fact that claimed compounds did not possess such activity was an unexpected result sufficient to establish unobviousness within the meaning of 35 U.S.C. 103.).

Jump to MPEP SourceUnexpected ResultsSecondary Considerations of NonobviousnessObviousness

Citations

Primary topicCitation
Establishing Prima Facie Case
Unexpected Results
35 U.S.C. § 103
35 U.S.C. 103 – Obviousness
Obviousness of Ranges and Values
MPEP § 2145
Establishing Prima Facie CaseIn re Chupp, 816 F.2d 643, 646, 2 USPQ2d 1437, 1439 (Fed. Cir. 1987)
35 U.S.C. 103 – Obviousness
Establishing Prima Facie Case
Obviousness
In re Corkill, 771 F.2d 1496, 226 USPQ 1005 (Fed. Cir. 1985)
35 U.S.C. 103 – Obviousness
Obviousness of Ranges and Values
In re Papesch, 315 F.2d 381, 137 USPQ 43 (CCPA 1963)
35 U.S.C. 103 – Obviousness
Obviousness of Ranges and Values
In re Payne, 606 F.2d 303, 203 USPQ 245 (CCPA 1979)

Source Text from USPTO’s MPEP

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BlueIron Last Updated: 2025-12-31