Where there is a reason to modify or combine the prior art to achieve the claimed invention, the claims may be rejected as prima facie obvious provided there is also a reasonable expectation of success. The reasonable expectation of success requirement refers to “the likelihood of success” in combining or modifying prior art disclosures to meet the limitations of the claimed invention. See Elekta Ltd. v. ZAP Surgical Sys., Inc., 81 F.4th 1368, 1375, 2023 USPQ2d 1100 (Fed. Cir. 2023) and Intelligent Bio-Sys., Inc. v. Illumina Cambridge Ltd., 821 F.3d 1359, 1367, 119 USPQ2d 1171, 1176 (Fed. Cir. 2016). See MPEP § 2143 for guidance on rationales for modifying or combining the prior art. In In re Merck & Co., Inc., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986), the Board affirmed a rejection of claims directed to a method of treating depression with amitriptyline (or nontoxic salts thereof) as prima facie obvious. The prior art disclosed that amitriptyline is a compound known to possess psychotropic properties and that imipramine is a structurally similar psychotropic compound known to possess antidepressive properties. Additional prior art, suggested that these compounds would have been expected to have similar activity because the structural difference between them involved a known bioisosteric replacement, and because a research paper comparing the pharmacological properties of these two compounds suggested clinical testing of amitriptyline as an antidepressant. The court affirmed the Board’s determination, finding that the teachings of the prior art provided a sufficient basis for a reasonable expectation of success.) In Ex parte Blanc, 13 USPQ2d 1383 (Bd. Pat. App. & Inter. 1989) (the claims were directed to a process of sterilizing a polyolefinic composition with high-energy radiation in the presence of a phenolic polyester antioxidant to inhibit discoloration or degradation of the polyolefin. Appellant argued that it is unpredictable whether a particular antioxidant will solve the problem of discoloration or degradation. However, the Board found that because the prior art taught that appellant’s preferred antioxidant is very efficient and provides better results compared with other prior art antioxidants, there would have been a reasonable expectation of success.).

Where there is a reason to modify or combine the prior art to achieve the claimed invention, the claims may be rejected as prima facie obvious provided there is also a reasonable expectation of success. The reasonable expectation of success requirement refers to “the likelihood of success” in combining or modifying prior art disclosures to meet the limitations of the claimed invention. See Elekta Ltd. v. ZAP Surgical Sys., Inc., 81 F.4th 1368, 1375, 2023 USPQ2d 1100 (Fed. Cir. 2023) and Intelligent Bio-Sys., Inc. v. Illumina Cambridge Ltd., 821 F.3d 1359, 1367, 119 USPQ2d 1171, 1176 (Fed. Cir. 2016). See MPEP § 2143 for guidance on rationales for modifying or combining the prior art. In In re Merck & Co., Inc., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986), the Board affirmed a rejection of claims directed to a method of treating depression with amitriptyline (or nontoxic salts thereof) as prima facie obvious. The prior art disclosed that amitriptyline is a compound known to possess psychotropic properties and that imipramine is a structurally similar psychotropic compound known to possess antidepressive properties. Additional prior art, suggested that these compounds would have been expected to have similar activity because the structural difference between them involved a known bioisosteric replacement, and because a research paper comparing the pharmacological properties of these two compounds suggested clinical testing of amitriptyline as an antidepressant. The court affirmed the Board’s determination, finding that the teachings of the prior art provided a sufficient basis for a reasonable expectation of success.) In Ex parte Blanc, 13 USPQ2d 1383 (Bd. Pat. App. & Inter. 1989) (the claims were directed to a process of sterilizing a polyolefinic composition with high-energy radiation in the presence of a phenolic polyester antioxidant to inhibit discoloration or degradation of the polyolefin. Appellant argued that it is unpredictable whether a particular antioxidant will solve the problem of discoloration or degradation. However, the Board found that because the prior art taught that appellant’s preferred antioxidant is very efficient and provides better results compared with other prior art antioxidants, there would have been a reasonable expectation of success.).

Where there is a reason to modify or combine the prior art to achieve the claimed invention, the claims may be rejected as prima facie obvious provided there is also a reasonable expectation of success. The reasonable expectation of success requirement refers to “the likelihood of success” in combining or modifying prior art disclosures to meet the limitations of the claimed invention. See Elekta Ltd. v. ZAP Surgical Sys., Inc., 81 F.4th 1368, 1375, 2023 USPQ2d 1100 (Fed. Cir. 2023) and Intelligent Bio-Sys., Inc. v. Illumina Cambridge Ltd., 821 F.3d 1359, 1367, 119 USPQ2d 1171, 1176 (Fed. Cir. 2016). See MPEP § 2143 for guidance on rationales for modifying or combining the prior art. In In re Merck & Co., Inc., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986), the Board affirmed a rejection of claims directed to a method of treating depression with amitriptyline (or nontoxic salts thereof) as prima facie obvious. The prior art disclosed that amitriptyline is a compound known to possess psychotropic properties and that imipramine is a structurally similar psychotropic compound known to possess antidepressive properties. Additional prior art, suggested that these compounds would have been expected to have similar activity because the structural difference between them involved a known bioisosteric replacement, and because a research paper comparing the pharmacological properties of these two compounds suggested clinical testing of amitriptyline as an antidepressant. The court affirmed the Board’s determination, finding that the teachings of the prior art provided a sufficient basis for a reasonable expectation of success.) In Ex parte Blanc, 13 USPQ2d 1383 (Bd. Pat. App. & Inter. 1989) (the claims were directed to a process of sterilizing a polyolefinic composition with high-energy radiation in the presence of a phenolic polyester antioxidant to inhibit discoloration or degradation of the polyolefin. Appellant argued that it is unpredictable whether a particular antioxidant will solve the problem of discoloration or degradation. However, the Board found that because the prior art taught that appellant’s preferred antioxidant is very efficient and provides better results compared with other prior art antioxidants, there would have been a reasonable expectation of success.).

Where there is a reason to modify or combine the prior art to achieve the claimed invention, the claims may be rejected as prima facie obvious provided there is also a reasonable expectation of success. The reasonable expectation of success requirement refers to “the likelihood of success” in combining or modifying prior art disclosures to meet the limitations of the claimed invention. See Elekta Ltd. v. ZAP Surgical Sys., Inc., 81 F.4th 1368, 1375, 2023 USPQ2d 1100 (Fed. Cir. 2023) and Intelligent Bio-Sys., Inc. v. Illumina Cambridge Ltd., 821 F.3d 1359, 1367, 119 USPQ2d 1171, 1176 (Fed. Cir. 2016). See MPEP § 2143 for guidance on rationales for modifying or combining the prior art. In In re Merck & Co., Inc., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986), the Board affirmed a rejection of claims directed to a method of treating depression with amitriptyline (or nontoxic salts thereof) as prima facie obvious. The prior art disclosed that amitriptyline is a compound known to possess psychotropic properties and that imipramine is a structurally similar psychotropic compound known to possess antidepressive properties. Additional prior art, suggested that these compounds would have been expected to have similar activity because the structural difference between them involved a known bioisosteric replacement, and because a research paper comparing the pharmacological properties of these two compounds suggested clinical testing of amitriptyline as an antidepressant. The court affirmed the Board’s determination, finding that the teachings of the prior art provided a sufficient basis for a reasonable expectation of success.) In Ex parte Blanc, 13 USPQ2d 1383 (Bd. Pat. App. & Inter. 1989) (the claims were directed to a process of sterilizing a polyolefinic composition with high-energy radiation in the presence of a phenolic polyester antioxidant to inhibit discoloration or degradation of the polyolefin. Appellant argued that it is unpredictable whether a particular antioxidant will solve the problem of discoloration or degradation. However, the Board found that because the prior art taught that appellant’s preferred antioxidant is very efficient and provides better results compared with other prior art antioxidants, there would have been a reasonable expectation of success.).

Where there is a reason to modify or combine the prior art to achieve the claimed invention, the claims may be rejected as prima facie obvious provided there is also a reasonable expectation of success. The reasonable expectation of success requirement refers to “the likelihood of success” in combining or modifying prior art disclosures to meet the limitations of the claimed invention. See Elekta Ltd. v. ZAP Surgical Sys., Inc., 81 F.4th 1368, 1375, 2023 USPQ2d 1100 (Fed. Cir. 2023) and Intelligent Bio-Sys., Inc. v. Illumina Cambridge Ltd., 821 F.3d 1359, 1367, 119 USPQ2d 1171, 1176 (Fed. Cir. 2016). See MPEP § 2143 for guidance on rationales for modifying or combining the prior art. In In re Merck & Co., Inc., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986), the Board affirmed a rejection of claims directed to a method of treating depression with amitriptyline (or nontoxic salts thereof) as prima facie obvious. The prior art disclosed that amitriptyline is a compound known to possess psychotropic properties and that imipramine is a structurally similar psychotropic compound known to possess antidepressive properties. Additional prior art, suggested that these compounds would have been expected to have similar activity because the structural difference between them involved a known bioisosteric replacement, and because a research paper comparing the pharmacological properties of these two compounds suggested clinical testing of amitriptyline as an antidepressant. The court affirmed the Board’s determination, finding that the teachings of the prior art provided a sufficient basis for a reasonable expectation of success.) In Ex parte Blanc, 13 USPQ2d 1383 (Bd. Pat. App. & Inter. 1989) (the claims were directed to a process of sterilizing a polyolefinic composition with high-energy radiation in the presence of a phenolic polyester antioxidant to inhibit discoloration or degradation of the polyolefin. Appellant argued that it is unpredictable whether a particular antioxidant will solve the problem of discoloration or degradation. However, the Board found that because the prior art taught that appellant’s preferred antioxidant is very efficient and provides better results compared with other prior art antioxidants, there would have been a reasonable expectation of success.).

Where there is a reason to modify or combine the prior art to achieve the claimed invention, the claims may be rejected as prima facie obvious provided there is also a reasonable expectation of success. The reasonable expectation of success requirement refers to “the likelihood of success” in combining or modifying prior art disclosures to meet the limitations of the claimed invention. See Elekta Ltd. v. ZAP Surgical Sys., Inc., 81 F.4th 1368, 1375, 2023 USPQ2d 1100 (Fed. Cir. 2023) and Intelligent Bio-Sys., Inc. v. Illumina Cambridge Ltd., 821 F.3d 1359, 1367, 119 USPQ2d 1171, 1176 (Fed. Cir. 2016). See MPEP § 2143 for guidance on rationales for modifying or combining the prior art. In In re Merck & Co., Inc., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986), the Board affirmed a rejection of claims directed to a method of treating depression with amitriptyline (or nontoxic salts thereof) as prima facie obvious. The prior art disclosed that amitriptyline is a compound known to possess psychotropic properties and that imipramine is a structurally similar psychotropic compound known to possess antidepressive properties. Additional prior art, suggested that these compounds would have been expected to have similar activity because the structural difference between them involved a known bioisosteric replacement, and because a research paper comparing the pharmacological properties of these two compounds suggested clinical testing of amitriptyline as an antidepressant. The court affirmed the Board’s determination, finding that the teachings of the prior art provided a sufficient basis for a reasonable expectation of success.) In Ex parte Blanc, 13 USPQ2d 1383 (Bd. Pat. App. & Inter. 1989) (the claims were directed to a process of sterilizing a polyolefinic composition with high-energy radiation in the presence of a phenolic polyester antioxidant to inhibit discoloration or degradation of the polyolefin. Appellant argued that it is unpredictable whether a particular antioxidant will solve the problem of discoloration or degradation. However, the Board found that because the prior art taught that appellant’s preferred antioxidant is very efficient and provides better results compared with other prior art antioxidants, there would have been a reasonable expectation of success.).

Where there is a reason to modify or combine the prior art to achieve the claimed invention, the claims may be rejected as prima facie obvious provided there is also a reasonable expectation of success. The reasonable expectation of success requirement refers to “the likelihood of success” in combining or modifying prior art disclosures to meet the limitations of the claimed invention. See Elekta Ltd. v. ZAP Surgical Sys., Inc., 81 F.4th 1368, 1375, 2023 USPQ2d 1100 (Fed. Cir. 2023) and Intelligent Bio-Sys., Inc. v. Illumina Cambridge Ltd., 821 F.3d 1359, 1367, 119 USPQ2d 1171, 1176 (Fed. Cir. 2016). See MPEP § 2143 for guidance on rationales for modifying or combining the prior art. In In re Merck & Co., Inc., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986), the Board affirmed a rejection of claims directed to a method of treating depression with amitriptyline (or nontoxic salts thereof) as prima facie obvious. The prior art disclosed that amitriptyline is a compound known to possess psychotropic properties and that imipramine is a structurally similar psychotropic compound known to possess antidepressive properties. Additional prior art, suggested that these compounds would have been expected to have similar activity because the structural difference between them involved a known bioisosteric replacement, and because a research paper comparing the pharmacological properties of these two compounds suggested clinical testing of amitriptyline as an antidepressant. The court affirmed the Board’s determination, finding that the teachings of the prior art provided a sufficient basis for a reasonable expectation of success.) In Ex parte Blanc, 13 USPQ2d 1383 (Bd. Pat. App. & Inter. 1989) (the claims were directed to a process of sterilizing a polyolefinic composition with high-energy radiation in the presence of a phenolic polyester antioxidant to inhibit discoloration or degradation of the polyolefin. Appellant argued that it is unpredictable whether a particular antioxidant will solve the problem of discoloration or degradation. However, the Board found that because the prior art taught that appellant’s preferred antioxidant is very efficient and provides better results compared with other prior art antioxidants, there would have been a reasonable expectation of success.).

Where there is a reason to modify or combine the prior art to achieve the claimed invention, the claims may be rejected as prima facie obvious provided there is also a reasonable expectation of success. The reasonable expectation of success requirement refers to “the likelihood of success” in combining or modifying prior art disclosures to meet the limitations of the claimed invention. See Elekta Ltd. v. ZAP Surgical Sys., Inc., 81 F.4th 1368, 1375, 2023 USPQ2d 1100 (Fed. Cir. 2023) and Intelligent Bio-Sys., Inc. v. Illumina Cambridge Ltd., 821 F.3d 1359, 1367, 119 USPQ2d 1171, 1176 (Fed. Cir. 2016). See MPEP § 2143 for guidance on rationales for modifying or combining the prior art. In In re Merck & Co., Inc., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986), the Board affirmed a rejection of claims directed to a method of treating depression with amitriptyline (or nontoxic salts thereof) as prima facie obvious. The prior art disclosed that amitriptyline is a compound known to possess psychotropic properties and that imipramine is a structurally similar psychotropic compound known to possess antidepressive properties. Additional prior art, suggested that these compounds would have been expected to have similar activity because the structural difference between them involved a known bioisosteric replacement, and because a research paper comparing the pharmacological properties of these two compounds suggested clinical testing of amitriptyline as an antidepressant. The court affirmed the Board’s determination, finding that the teachings of the prior art provided a sufficient basis for a reasonable expectation of success.) In Ex parte Blanc, 13 USPQ2d 1383 (Bd. Pat. App. & Inter. 1989) (the claims were directed to a process of sterilizing a polyolefinic composition with high-energy radiation in the presence of a phenolic polyester antioxidant to inhibit discoloration or degradation of the polyolefin. Appellant argued that it is unpredictable whether a particular antioxidant will solve the problem of discoloration or degradation. However, the Board found that because the prior art taught that appellant’s preferred antioxidant is very efficient and provides better results compared with other prior art antioxidants, there would have been a reasonable expectation of success.).

As discussed above, reasonable expectation of success can be implicitly shown via the prior art teachings or as part of the obviousness analysis. See Elekta Ltd. v. ZAP Surgical Sys., Inc., 81 F.4th 1368, 1376-77, 2023 USPQ2d 1100 (Fed. Cir. 2023) (“[W]e can reasonably discern that the Board considered and implicitly addressed reasonable expectation of success based on the arguments and evidence presented to the Board on motivation to combine.”). In this decision, the court found the Board’s explanation on why the patent owner's arguments and evidence presented on motivation to combine were not persuasive implicitly addressed reasonable expectation of success and was supported by substantial evidence. On the other hand, depending on the situation (e.g., the technology, the prior art teachings and the obviousness analysis), reliance on an implicit showing of reasonable expectation of success may not be sufficient to establish a prima facie showing of obviousness. Eli Lilly & Co. v. Teva Pharms. Int’l GmbH, 8 F.4th 1331, 1344, 2021 USPQ2d 862 (Fed. Cir. 2021) (A finding that a patent challenger in an inter partes review had demonstrated a motivation to combine references does not necessarily imply that the challenger had also met its burden of showing a reasonable expectation of success in achieving a claimed method of treatment.). In this case, the court found that the challenged method of treating claims “contain limitations related to their intended purpose for treating vasomotor symptoms [as stated in the preamble], and thus those limitations are undoubtedly relevant to the reasonable expectation of success.” Id. at 1345. In other words, the court found that the preamble was limiting and applicable to reasonable expectation of success. However, the limitations in the preamble were not addressed in the motivation to combine analysis. Any obviousness rejection should include, either explicitly or implicitly, an indication of a reasonable expectation of success.

As discussed above, reasonable expectation of success can be implicitly shown via the prior art teachings or as part of the obviousness analysis. See Elekta Ltd. v. ZAP Surgical Sys., Inc., 81 F.4th 1368, 1376-77, 2023 USPQ2d 1100 (Fed. Cir. 2023) (“[W]e can reasonably discern that the Board considered and implicitly addressed reasonable expectation of success based on the arguments and evidence presented to the Board on motivation to combine.”). In this decision, the court found the Board’s explanation on why the patent owner's arguments and evidence presented on motivation to combine were not persuasive implicitly addressed reasonable expectation of success and was supported by substantial evidence. On the other hand, depending on the situation (e.g., the technology, the prior art teachings and the obviousness analysis), reliance on an implicit showing of reasonable expectation of success may not be sufficient to establish a prima facie showing of obviousness. Eli Lilly & Co. v. Teva Pharms. Int’l GmbH, 8 F.4th 1331, 1344, 2021 USPQ2d 862 (Fed. Cir. 2021) (A finding that a patent challenger in an inter partes review had demonstrated a motivation to combine references does not necessarily imply that the challenger had also met its burden of showing a reasonable expectation of success in achieving a claimed method of treatment.). In this case, the court found that the challenged method of treating claims “contain limitations related to their intended purpose for treating vasomotor symptoms [as stated in the preamble], and thus those limitations are undoubtedly relevant to the reasonable expectation of success.” Id. at 1345. In other words, the court found that the preamble was limiting and applicable to reasonable expectation of success. However, the limitations in the preamble were not addressed in the motivation to combine analysis. Any obviousness rejection should include, either explicitly or implicitly, an indication of a reasonable expectation of success.

Where there is a reason to modify or combine the prior art to achieve the claimed invention, the claims may be rejected as prima facie obvious provided there is also a reasonable expectation of success. The reasonable expectation of success requirement refers to “the likelihood of success” in combining or modifying prior art disclosures to meet the limitations of the claimed invention. See Elekta Ltd. v. ZAP Surgical Sys., Inc., 81 F.4th 1368, 1375, 2023 USPQ2d 1100 (Fed. Cir. 2023) and Intelligent Bio-Sys., Inc. v. Illumina Cambridge Ltd., 821 F.3d 1359, 1367, 119 USPQ2d 1171, 1176 (Fed. Cir. 2016). See MPEP § 2143 for guidance on rationales for modifying or combining the prior art. In In re Merck & Co., Inc., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986), the Board affirmed a rejection of claims directed to a method of treating depression with amitriptyline (or nontoxic salts thereof) as prima facie obvious. The prior art disclosed that amitriptyline is a compound known to possess psychotropic properties and that imipramine is a structurally similar psychotropic compound known to possess antidepressive properties. Additional prior art, suggested that these compounds would have been expected to have similar activity because the structural difference between them involved a known bioisosteric replacement, and because a research paper comparing the pharmacological properties of these two compounds suggested clinical testing of amitriptyline as an antidepressant. The court affirmed the Board’s determination, finding that the teachings of the prior art provided a sufficient basis for a reasonable expectation of success.) In Ex parte Blanc, 13 USPQ2d 1383 (Bd. Pat. App. & Inter. 1989) (the claims were directed to a process of sterilizing a polyolefinic composition with high-energy radiation in the presence of a phenolic polyester antioxidant to inhibit discoloration or degradation of the polyolefin. Appellant argued that it is unpredictable whether a particular antioxidant will solve the problem of discoloration or degradation. However, the Board found that because the prior art taught that appellant’s preferred antioxidant is very efficient and provides better results compared with other prior art antioxidants, there would have been a reasonable expectation of success.).

As discussed above, reasonable expectation of success can be implicitly shown via the prior art teachings or as part of the obviousness analysis. See Elekta Ltd. v. ZAP Surgical Sys., Inc., 81 F.4th 1368, 1376-77, 2023 USPQ2d 1100 (Fed. Cir. 2023) (“[W]e can reasonably discern that the Board considered and implicitly addressed reasonable expectation of success based on the arguments and evidence presented to the Board on motivation to combine.”). In this decision, the court found the Board’s explanation on why the patent owner's arguments and evidence presented on motivation to combine were not persuasive implicitly addressed reasonable expectation of success and was supported by substantial evidence. On the other hand, depending on the situation (e.g., the technology, the prior art teachings and the obviousness analysis), reliance on an implicit showing of reasonable expectation of success may not be sufficient to establish a prima facie showing of obviousness. Eli Lilly & Co. v. Teva Pharms. Int’l GmbH, 8 F.4th 1331, 1344, 2021 USPQ2d 862 (Fed. Cir. 2021) (A finding that a patent challenger in an inter partes review had demonstrated a motivation to combine references does not necessarily imply that the challenger had also met its burden of showing a reasonable expectation of success in achieving a claimed method of treatment.). In this case, the court found that the challenged method of treating claims “contain limitations related to their intended purpose for treating vasomotor symptoms [as stated in the preamble], and thus those limitations are undoubtedly relevant to the reasonable expectation of success.” Id. at 1345. In other words, the court found that the preamble was limiting and applicable to reasonable expectation of success. However, the limitations in the preamble were not addressed in the motivation to combine analysis. Any obviousness rejection should include, either explicitly or implicitly, an indication of a reasonable expectation of success.

As discussed above, reasonable expectation of success can be implicitly shown via the prior art teachings or as part of the obviousness analysis. See Elekta Ltd. v. ZAP Surgical Sys., Inc., 81 F.4th 1368, 1376-77, 2023 USPQ2d 1100 (Fed. Cir. 2023) (“[W]e can reasonably discern that the Board considered and implicitly addressed reasonable expectation of success based on the arguments and evidence presented to the Board on motivation to combine.”). In this decision, the court found the Board’s explanation on why the patent owner's arguments and evidence presented on motivation to combine were not persuasive implicitly addressed reasonable expectation of success and was supported by substantial evidence. On the other hand, depending on the situation (e.g., the technology, the prior art teachings and the obviousness analysis), reliance on an implicit showing of reasonable expectation of success may not be sufficient to establish a prima facie showing of obviousness. Eli Lilly & Co. v. Teva Pharms. Int’l GmbH, 8 F.4th 1331, 1344, 2021 USPQ2d 862 (Fed. Cir. 2021) (A finding that a patent challenger in an inter partes review had demonstrated a motivation to combine references does not necessarily imply that the challenger had also met its burden of showing a reasonable expectation of success in achieving a claimed method of treatment.). In this case, the court found that the challenged method of treating claims “contain limitations related to their intended purpose for treating vasomotor symptoms [as stated in the preamble], and thus those limitations are undoubtedly relevant to the reasonable expectation of success.” Id. at 1345. In other words, the court found that the preamble was limiting and applicable to reasonable expectation of success. However, the limitations in the preamble were not addressed in the motivation to combine analysis. Any obviousness rejection should include, either explicitly or implicitly, an indication of a reasonable expectation of success.

Conclusive proof of efficacy is not required to show a reasonable expectation of success. OSI Pharm., LLC v. Apotex Inc., 939 F.3d 1375, 1385, 2019 USPQ2d 379681 (Fed. Cir. 2019) (“To be clear, we do not hold today that efficacy data is always required for a reasonable expectation of success. Nor are we requiring ‘absolute predictability of success.’”); Acorda Therapeutics, Inc. v. Roxane Lab., Inc., 903 F.3d 1310, 1333, 128 USPQ2d 1001, 1018 (Fed. Cir. 2018) (“This court has long rejected a requirement of ‘[c]onclusive proof of efficacy’ for obviousness.” (citing to Hoffmann-La Roche Inc. v. Apotex Inc., 748 F.3d 1326, 1331 (Fed. Cir. 2014); PharmaStem Therapeutics, Inc. v. ViaCell, Inc., 491 F.3d 1342, 1364 (Fed. Cir. 2007); Pfizer, Inc. v. Apotex, Inc., 480 F.3d 1348, 1364, 1367–68 (Fed. Cir. 2007) (reasoning that “the expectation of success need only be reasonable, not absolute”)).

Conclusive proof of efficacy is not required to show a reasonable expectation of success. OSI Pharm., LLC v. Apotex Inc., 939 F.3d 1375, 1385, 2019 USPQ2d 379681 (Fed. Cir. 2019) (“To be clear, we do not hold today that efficacy data is always required for a reasonable expectation of success. Nor are we requiring ‘absolute predictability of success.’”); Acorda Therapeutics, Inc. v. Roxane Lab., Inc., 903 F.3d 1310, 1333, 128 USPQ2d 1001, 1018 (Fed. Cir. 2018) (“This court has long rejected a requirement of ‘[c]onclusive proof of efficacy’ for obviousness.” (citing to Hoffmann-La Roche Inc. v. Apotex Inc., 748 F.3d 1326, 1331 (Fed. Cir. 2014); PharmaStem Therapeutics, Inc. v. ViaCell, Inc., 491 F.3d 1342, 1364 (Fed. Cir. 2007); Pfizer, Inc. v. Apotex, Inc., 480 F.3d 1348, 1364, 1367–68 (Fed. Cir. 2007) (reasoning that “the expectation of success need only be reasonable, not absolute”)).

Conclusive proof of efficacy is not required to show a reasonable expectation of success. OSI Pharm., LLC v. Apotex Inc., 939 F.3d 1375, 1385, 2019 USPQ2d 379681 (Fed. Cir. 2019) (“To be clear, we do not hold today that efficacy data is always required for a reasonable expectation of success. Nor are we requiring ‘absolute predictability of success.’”); Acorda Therapeutics, Inc. v. Roxane Lab., Inc., 903 F.3d 1310, 1333, 128 USPQ2d 1001, 1018 (Fed. Cir. 2018) (“This court has long rejected a requirement of ‘[c]onclusive proof of efficacy’ for obviousness.” (citing to Hoffmann-La Roche Inc. v. Apotex Inc., 748 F.3d 1326, 1331 (Fed. Cir. 2014); PharmaStem Therapeutics, Inc. v. ViaCell, Inc., 491 F.3d 1342, 1364 (Fed. Cir. 2007); Pfizer, Inc. v. Apotex, Inc., 480 F.3d 1348, 1364, 1367–68 (Fed. Cir. 2007) (reasoning that “the expectation of success need only be reasonable, not absolute”)).

Conclusive proof of efficacy is not required to show a reasonable expectation of success. OSI Pharm., LLC v. Apotex Inc., 939 F.3d 1375, 1385, 2019 USPQ2d 379681 (Fed. Cir. 2019) (“To be clear, we do not hold today that efficacy data is always required for a reasonable expectation of success. Nor are we requiring ‘absolute predictability of success.’”); Acorda Therapeutics, Inc. v. Roxane Lab., Inc., 903 F.3d 1310, 1333, 128 USPQ2d 1001, 1018 (Fed. Cir. 2018) (“This court has long rejected a requirement of ‘[c]onclusive proof of efficacy’ for obviousness.” (citing to Hoffmann-La Roche Inc. v. Apotex Inc., 748 F.3d 1326, 1331 (Fed. Cir. 2014); PharmaStem Therapeutics, Inc. v. ViaCell, Inc., 491 F.3d 1342, 1364 (Fed. Cir. 2007); Pfizer, Inc. v. Apotex, Inc., 480 F.3d 1348, 1364, 1367–68 (Fed. Cir. 2007) (reasoning that “the expectation of success need only be reasonable, not absolute”)).

Obviousness does not require absolute predictability, but at least some degree of predictability is required. Evidence showing there was no reasonable expectation of success may support a conclusion of nonobviousness. In re Rinehart, 531 F.2d 1048, 189 USPQ 143 (CCPA 1976) (Claims directed to a method for the commercial scale production of polyesters in the presence of a solvent at superatmospheric pressure were rejected as obvious over a reference which taught the claimed method at atmospheric pressure in view of a reference which taught the claimed process except for the presence of a solvent. The court reversed, finding there was no reasonable expectation that a process combining the prior art steps could be successfully scaled up in view of unchallenged evidence showing that the prior art processes individually could not be commercially scaled up successfully.). See also OSI Pharm., LLC v. Apotex Inc., 939 F.3d 1375, 1385, 2019 USPQ2d 379681 (Fed. Cir. 2019) (“These references provide no more than hope—and hope that a potentially promising drug will treat a particular cancer is not enough to create a reasonable expectation of success in a highly unpredictable art such as this. Indeed, given a 99.5% failure rate and no efficacy data or any other reliable indicator of success, the only reasonable expectation at the time of the invention was failure, not success.”); Amgen, Inc. v. Chugai Pharm. Co., 927 F.2d 1200, 1207-08, 18 USPQ2d 1016, 1022-23 (Fed. Cir. 1991), cert. denied, 502 U.S. 856 (1991) (In the context of a biotechnology case, testimony supported the conclusion that the references did not show that there was a reasonable expectation of success.); In re O’Farrell, 853 F.2d 894, 903, 7 USPQ2d 1673, 1681 (Fed. Cir. 1988) (The court held the claimed method would have been obvious over the prior art relied upon because one reference contained a detailed enabling methodology, a suggestion to modify the prior art to produce the claimed invention, and evidence suggesting the modification would be successful.).

Obviousness does not require absolute predictability, but at least some degree of predictability is required. Evidence showing there was no reasonable expectation of success may support a conclusion of nonobviousness. In re Rinehart, 531 F.2d 1048, 189 USPQ 143 (CCPA 1976) (Claims directed to a method for the commercial scale production of polyesters in the presence of a solvent at superatmospheric pressure were rejected as obvious over a reference which taught the claimed method at atmospheric pressure in view of a reference which taught the claimed process except for the presence of a solvent. The court reversed, finding there was no reasonable expectation that a process combining the prior art steps could be successfully scaled up in view of unchallenged evidence showing that the prior art processes individually could not be commercially scaled up successfully.). See also OSI Pharm., LLC v. Apotex Inc., 939 F.3d 1375, 1385, 2019 USPQ2d 379681 (Fed. Cir. 2019) (“These references provide no more than hope—and hope that a potentially promising drug will treat a particular cancer is not enough to create a reasonable expectation of success in a highly unpredictable art such as this. Indeed, given a 99.5% failure rate and no efficacy data or any other reliable indicator of success, the only reasonable expectation at the time of the invention was failure, not success.”); Amgen, Inc. v. Chugai Pharm. Co., 927 F.2d 1200, 1207-08, 18 USPQ2d 1016, 1022-23 (Fed. Cir. 1991), cert. denied, 502 U.S. 856 (1991) (In the context of a biotechnology case, testimony supported the conclusion that the references did not show that there was a reasonable expectation of success.); In re O’Farrell, 853 F.2d 894, 903, 7 USPQ2d 1673, 1681 (Fed. Cir. 1988) (The court held the claimed method would have been obvious over the prior art relied upon because one reference contained a detailed enabling methodology, a suggestion to modify the prior art to produce the claimed invention, and evidence suggesting the modification would be successful.).

Obviousness does not require absolute predictability, but at least some degree of predictability is required. Evidence showing there was no reasonable expectation of success may support a conclusion of nonobviousness. In re Rinehart, 531 F.2d 1048, 189 USPQ 143 (CCPA 1976) (Claims directed to a method for the commercial scale production of polyesters in the presence of a solvent at superatmospheric pressure were rejected as obvious over a reference which taught the claimed method at atmospheric pressure in view of a reference which taught the claimed process except for the presence of a solvent. The court reversed, finding there was no reasonable expectation that a process combining the prior art steps could be successfully scaled up in view of unchallenged evidence showing that the prior art processes individually could not be commercially scaled up successfully.). See also OSI Pharm., LLC v. Apotex Inc., 939 F.3d 1375, 1385, 2019 USPQ2d 379681 (Fed. Cir. 2019) (“These references provide no more than hope—and hope that a potentially promising drug will treat a particular cancer is not enough to create a reasonable expectation of success in a highly unpredictable art such as this. Indeed, given a 99.5% failure rate and no efficacy data or any other reliable indicator of success, the only reasonable expectation at the time of the invention was failure, not success.”); Amgen, Inc. v. Chugai Pharm. Co., 927 F.2d 1200, 1207-08, 18 USPQ2d 1016, 1022-23 (Fed. Cir. 1991), cert. denied, 502 U.S. 856 (1991) (In the context of a biotechnology case, testimony supported the conclusion that the references did not show that there was a reasonable expectation of success.); In re O’Farrell, 853 F.2d 894, 903, 7 USPQ2d 1673, 1681 (Fed. Cir. 1988) (The court held the claimed method would have been obvious over the prior art relied upon because one reference contained a detailed enabling methodology, a suggestion to modify the prior art to produce the claimed invention, and evidence suggesting the modification would be successful.).

Obviousness does not require absolute predictability, but at least some degree of predictability is required. Evidence showing there was no reasonable expectation of success may support a conclusion of nonobviousness. In re Rinehart, 531 F.2d 1048, 189 USPQ 143 (CCPA 1976) (Claims directed to a method for the commercial scale production of polyesters in the presence of a solvent at superatmospheric pressure were rejected as obvious over a reference which taught the claimed method at atmospheric pressure in view of a reference which taught the claimed process except for the presence of a solvent. The court reversed, finding there was no reasonable expectation that a process combining the prior art steps could be successfully scaled up in view of unchallenged evidence showing that the prior art processes individually could not be commercially scaled up successfully.). See also OSI Pharm., LLC v. Apotex Inc., 939 F.3d 1375, 1385, 2019 USPQ2d 379681 (Fed. Cir. 2019) (“These references provide no more than hope—and hope that a potentially promising drug will treat a particular cancer is not enough to create a reasonable expectation of success in a highly unpredictable art such as this. Indeed, given a 99.5% failure rate and no efficacy data or any other reliable indicator of success, the only reasonable expectation at the time of the invention was failure, not success.”); Amgen, Inc. v. Chugai Pharm. Co., 927 F.2d 1200, 1207-08, 18 USPQ2d 1016, 1022-23 (Fed. Cir. 1991), cert. denied, 502 U.S. 856 (1991) (In the context of a biotechnology case, testimony supported the conclusion that the references did not show that there was a reasonable expectation of success.); In re O’Farrell, 853 F.2d 894, 903, 7 USPQ2d 1673, 1681 (Fed. Cir. 1988) (The court held the claimed method would have been obvious over the prior art relied upon because one reference contained a detailed enabling methodology, a suggestion to modify the prior art to produce the claimed invention, and evidence suggesting the modification would be successful.).

Obviousness does not require absolute predictability, but at least some degree of predictability is required. Evidence showing there was no reasonable expectation of success may support a conclusion of nonobviousness. In re Rinehart, 531 F.2d 1048, 189 USPQ 143 (CCPA 1976) (Claims directed to a method for the commercial scale production of polyesters in the presence of a solvent at superatmospheric pressure were rejected as obvious over a reference which taught the claimed method at atmospheric pressure in view of a reference which taught the claimed process except for the presence of a solvent. The court reversed, finding there was no reasonable expectation that a process combining the prior art steps could be successfully scaled up in view of unchallenged evidence showing that the prior art processes individually could not be commercially scaled up successfully.). See also OSI Pharm., LLC v. Apotex Inc., 939 F.3d 1375, 1385, 2019 USPQ2d 379681 (Fed. Cir. 2019) (“These references provide no more than hope—and hope that a potentially promising drug will treat a particular cancer is not enough to create a reasonable expectation of success in a highly unpredictable art such as this. Indeed, given a 99.5% failure rate and no efficacy data or any other reliable indicator of success, the only reasonable expectation at the time of the invention was failure, not success.”); Amgen, Inc. v. Chugai Pharm. Co., 927 F.2d 1200, 1207-08, 18 USPQ2d 1016, 1022-23 (Fed. Cir. 1991), cert. denied, 502 U.S. 856 (1991) (In the context of a biotechnology case, testimony supported the conclusion that the references did not show that there was a reasonable expectation of success.); In re O’Farrell, 853 F.2d 894, 903, 7 USPQ2d 1673, 1681 (Fed. Cir. 1988) (The court held the claimed method would have been obvious over the prior art relied upon because one reference contained a detailed enabling methodology, a suggestion to modify the prior art to produce the claimed invention, and evidence suggesting the modification would be successful.).

Obviousness does not require absolute predictability, but at least some degree of predictability is required. Evidence showing there was no reasonable expectation of success may support a conclusion of nonobviousness. In re Rinehart, 531 F.2d 1048, 189 USPQ 143 (CCPA 1976) (Claims directed to a method for the commercial scale production of polyesters in the presence of a solvent at superatmospheric pressure were rejected as obvious over a reference which taught the claimed method at atmospheric pressure in view of a reference which taught the claimed process except for the presence of a solvent. The court reversed, finding there was no reasonable expectation that a process combining the prior art steps could be successfully scaled up in view of unchallenged evidence showing that the prior art processes individually could not be commercially scaled up successfully.). See also OSI Pharm., LLC v. Apotex Inc., 939 F.3d 1375, 1385, 2019 USPQ2d 379681 (Fed. Cir. 2019) (“These references provide no more than hope—and hope that a potentially promising drug will treat a particular cancer is not enough to create a reasonable expectation of success in a highly unpredictable art such as this. Indeed, given a 99.5% failure rate and no efficacy data or any other reliable indicator of success, the only reasonable expectation at the time of the invention was failure, not success.”); Amgen, Inc. v. Chugai Pharm. Co., 927 F.2d 1200, 1207-08, 18 USPQ2d 1016, 1022-23 (Fed. Cir. 1991), cert. denied, 502 U.S. 856 (1991) (In the context of a biotechnology case, testimony supported the conclusion that the references did not show that there was a reasonable expectation of success.); In re O’Farrell, 853 F.2d 894, 903, 7 USPQ2d 1673, 1681 (Fed. Cir. 1988) (The court held the claimed method would have been obvious over the prior art relied upon because one reference contained a detailed enabling methodology, a suggestion to modify the prior art to produce the claimed invention, and evidence suggesting the modification would be successful.).

As discussed above, reasonable expectation of success can be implicitly shown via the prior art teachings or as part of the obviousness analysis. See Elekta Ltd. v. ZAP Surgical Sys., Inc., 81 F.4th 1368, 1376-77, 2023 USPQ2d 1100 (Fed. Cir. 2023) (“[W]e can reasonably discern that the Board considered and implicitly addressed reasonable expectation of success based on the arguments and evidence presented to the Board on motivation to combine.”). In this decision, the court found the Board’s explanation on why the patent owner's arguments and evidence presented on motivation to combine were not persuasive implicitly addressed reasonable expectation of success and was supported by substantial evidence. On the other hand, depending on the situation (e.g., the technology, the prior art teachings and the obviousness analysis), reliance on an implicit showing of reasonable expectation of success may not be sufficient to establish a prima facie showing of obviousness. Eli Lilly & Co. v. Teva Pharms. Int’l GmbH, 8 F.4th 1331, 1344, 2021 USPQ2d 862 (Fed. Cir. 2021) (A finding that a patent challenger in an inter partes review had demonstrated a motivation to combine references does not necessarily imply that the challenger had also met its burden of showing a reasonable expectation of success in achieving a claimed method of treatment.). In this case, the court found that the challenged method of treating claims “contain limitations related to their intended purpose for treating vasomotor symptoms [as stated in the preamble], and thus those limitations are undoubtedly relevant to the reasonable expectation of success.” Id. at 1345. In other words, the court found that the preamble was limiting and applicable to reasonable expectation of success. However, the limitations in the preamble were not addressed in the motivation to combine analysis. Any obviousness rejection should include, either explicitly or implicitly, an indication of a reasonable expectation of success.

As discussed above, reasonable expectation of success can be implicitly shown via the prior art teachings or as part of the obviousness analysis. See Elekta Ltd. v. ZAP Surgical Sys., Inc., 81 F.4th 1368, 1376-77, 2023 USPQ2d 1100 (Fed. Cir. 2023) (“[W]e can reasonably discern that the Board considered and implicitly addressed reasonable expectation of success based on the arguments and evidence presented to the Board on motivation to combine.”). In this decision, the court found the Board’s explanation on why the patent owner's arguments and evidence presented on motivation to combine were not persuasive implicitly addressed reasonable expectation of success and was supported by substantial evidence. On the other hand, depending on the situation (e.g., the technology, the prior art teachings and the obviousness analysis), reliance on an implicit showing of reasonable expectation of success may not be sufficient to establish a prima facie showing of obviousness. Eli Lilly & Co. v. Teva Pharms. Int’l GmbH, 8 F.4th 1331, 1344, 2021 USPQ2d 862 (Fed. Cir. 2021) (A finding that a patent challenger in an inter partes review had demonstrated a motivation to combine references does not necessarily imply that the challenger had also met its burden of showing a reasonable expectation of success in achieving a claimed method of treatment.). In this case, the court found that the challenged method of treating claims “contain limitations related to their intended purpose for treating vasomotor symptoms [as stated in the preamble], and thus those limitations are undoubtedly relevant to the reasonable expectation of success.” Id. at 1345. In other words, the court found that the preamble was limiting and applicable to reasonable expectation of success. However, the limitations in the preamble were not addressed in the motivation to combine analysis. Any obviousness rejection should include, either explicitly or implicitly, an indication of a reasonable expectation of success.

As discussed above, reasonable expectation of success can be implicitly shown via the prior art teachings or as part of the obviousness analysis. See Elekta Ltd. v. ZAP Surgical Sys., Inc., 81 F.4th 1368, 1376-77, 2023 USPQ2d 1100 (Fed. Cir. 2023) (“[W]e can reasonably discern that the Board considered and implicitly addressed reasonable expectation of success based on the arguments and evidence presented to the Board on motivation to combine.”). In this decision, the court found the Board’s explanation on why the patent owner's arguments and evidence presented on motivation to combine were not persuasive implicitly addressed reasonable expectation of success and was supported by substantial evidence. On the other hand, depending on the situation (e.g., the technology, the prior art teachings and the obviousness analysis), reliance on an implicit showing of reasonable expectation of success may not be sufficient to establish a prima facie showing of obviousness. Eli Lilly & Co. v. Teva Pharms. Int’l GmbH, 8 F.4th 1331, 1344, 2021 USPQ2d 862 (Fed. Cir. 2021) (A finding that a patent challenger in an inter partes review had demonstrated a motivation to combine references does not necessarily imply that the challenger had also met its burden of showing a reasonable expectation of success in achieving a claimed method of treatment.). In this case, the court found that the challenged method of treating claims “contain limitations related to their intended purpose for treating vasomotor symptoms [as stated in the preamble], and thus those limitations are undoubtedly relevant to the reasonable expectation of success.” Id. at 1345. In other words, the court found that the preamble was limiting and applicable to reasonable expectation of success. However, the limitations in the preamble were not addressed in the motivation to combine analysis. Any obviousness rejection should include, either explicitly or implicitly, an indication of a reasonable expectation of success.

As discussed above, reasonable expectation of success can be implicitly shown via the prior art teachings or as part of the obviousness analysis. See Elekta Ltd. v. ZAP Surgical Sys., Inc., 81 F.4th 1368, 1376-77, 2023 USPQ2d 1100 (Fed. Cir. 2023) (“[W]e can reasonably discern that the Board considered and implicitly addressed reasonable expectation of success based on the arguments and evidence presented to the Board on motivation to combine.”). In this decision, the court found the Board’s explanation on why the patent owner's arguments and evidence presented on motivation to combine were not persuasive implicitly addressed reasonable expectation of success and was supported by substantial evidence. On the other hand, depending on the situation (e.g., the technology, the prior art teachings and the obviousness analysis), reliance on an implicit showing of reasonable expectation of success may not be sufficient to establish a prima facie showing of obviousness. Eli Lilly & Co. v. Teva Pharms. Int’l GmbH, 8 F.4th 1331, 1344, 2021 USPQ2d 862 (Fed. Cir. 2021) (A finding that a patent challenger in an inter partes review had demonstrated a motivation to combine references does not necessarily imply that the challenger had also met its burden of showing a reasonable expectation of success in achieving a claimed method of treatment.). In this case, the court found that the challenged method of treating claims “contain limitations related to their intended purpose for treating vasomotor symptoms [as stated in the preamble], and thus those limitations are undoubtedly relevant to the reasonable expectation of success.” Id. at 1345. In other words, the court found that the preamble was limiting and applicable to reasonable expectation of success. However, the limitations in the preamble were not addressed in the motivation to combine analysis. Any obviousness rejection should include, either explicitly or implicitly, an indication of a reasonable expectation of success.

[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.]

[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.]

As discussed above, reasonable expectation of success can be implicitly shown via the prior art teachings or as part of the obviousness analysis. See Elekta Ltd. v. ZAP Surgical Sys., Inc., 81 F.4th 1368, 1376-77, 2023 USPQ2d 1100 (Fed. Cir. 2023) (“[W]e can reasonably discern that the Board considered and implicitly addressed reasonable expectation of success based on the arguments and evidence presented to the Board on motivation to combine.”). In this decision, the court found the Board’s explanation on why the patent owner's arguments and evidence presented on motivation to combine were not persuasive implicitly addressed reasonable expectation of success and was supported by substantial evidence. On the other hand, depending on the situation (e.g., the technology, the prior art teachings and the obviousness analysis), reliance on an implicit showing of reasonable expectation of success may not be sufficient to establish a prima facie showing of obviousness. Eli Lilly & Co. v. Teva Pharms. Int’l GmbH, 8 F.4th 1331, 1344, 2021 USPQ2d 862 (Fed. Cir. 2021) (A finding that a patent challenger in an inter partes review had demonstrated a motivation to combine references does not necessarily imply that the challenger had also met its burden of showing a reasonable expectation of success in achieving a claimed method of treatment.). In this case, the court found that the challenged method of treating claims “contain limitations related to their intended purpose for treating vasomotor symptoms [as stated in the preamble], and thus those limitations are undoubtedly relevant to the reasonable expectation of success.” Id. at 1345. In other words, the court found that the preamble was limiting and applicable to reasonable expectation of success. However, the limitations in the preamble were not addressed in the motivation to combine analysis. Any obviousness rejection should include, either explicitly or implicitly, an indication of a reasonable expectation of success.

As discussed above, reasonable expectation of success can be implicitly shown via the prior art teachings or as part of the obviousness analysis. See Elekta Ltd. v. ZAP Surgical Sys., Inc., 81 F.4th 1368, 1376-77, 2023 USPQ2d 1100 (Fed. Cir. 2023) (“[W]e can reasonably discern that the Board considered and implicitly addressed reasonable expectation of success based on the arguments and evidence presented to the Board on motivation to combine.”). In this decision, the court found the Board’s explanation on why the patent owner's arguments and evidence presented on motivation to combine were not persuasive implicitly addressed reasonable expectation of success and was supported by substantial evidence. On the other hand, depending on the situation (e.g., the technology, the prior art teachings and the obviousness analysis), reliance on an implicit showing of reasonable expectation of success may not be sufficient to establish a prima facie showing of obviousness. Eli Lilly & Co. v. Teva Pharms. Int’l GmbH, 8 F.4th 1331, 1344, 2021 USPQ2d 862 (Fed. Cir. 2021) (A finding that a patent challenger in an inter partes review had demonstrated a motivation to combine references does not necessarily imply that the challenger had also met its burden of showing a reasonable expectation of success in achieving a claimed method of treatment.). In this case, the court found that the challenged method of treating claims “contain limitations related to their intended purpose for treating vasomotor symptoms [as stated in the preamble], and thus those limitations are undoubtedly relevant to the reasonable expectation of success.” Id. at 1345. In other words, the court found that the preamble was limiting and applicable to reasonable expectation of success. However, the limitations in the preamble were not addressed in the motivation to combine analysis. Any obviousness rejection should include, either explicitly or implicitly, an indication of a reasonable expectation of success.