Imagine That IP Law Blog

In an Inter Partes Review (IPR), the burden of proof and persuasion lies with the petitioner to demonstrate "unpatentability by a preponderance of the evidence" under 35 U.S.C. § 316(e). “[T]hat burden never shifts to the patentee.” Dynamic Drinkware, LLC v. Nat'l Graphics, Inc., 800 F.3d 1375, 1378-79 (Fed. Cir. 2015). Accordingly, to invalidate a claim in an IPR, the petitioner must establish by a preponderance of the evidence, that a claim in a patent is unpatentable.

To prove that a claim is unpatentable for violating “obviousness” requirements under 35 U.S.C §103, a petitioner is required to show that a person skilled in the art would have been motivated to combine or modify prior art teachings and would have a reasonable expectation of success in doing so.  Specifically, “[a]n obviousness determination requires finding that a POSITA [Person Of Ordinary Skill In The Art] would have been motivated to combine or modify the teachings in the prior art and would have had a reasonable expectation of success in doing so.” Endo Pharm., Inc. v. Actavis LLC, 922 F.3d 1365, 1373 (Fed. Cir. 2019) (emphasis added). Further, “[w]hether there was a motivation to combine references, and a reasonable expectation of success in doing so to meet the limitations of the claimed invention are questions of fact.” Samsung Elecs. Co. v. Elm 3DS Innovations, LLC, 925 F.3d 1373, 1380 (Fed. Cir. 2019) (emphasis added).

As factual questions, they require substantiation. Specifically, "a conclusory assertion with no explanation is inadequate to support a finding that there would have been a motivation to combine" (TQ Delta, LLC v. Cisco Sys., 942 F.3d 1352, 1359 (Fed. Cir. 2019).  Accordingly, the petitioner must identify the evidence supporting the challenge to each claim with particularity to meet their burden. 

For an IPR to be instituted by the Patent Trials and Appeals Board (PTAB), the Petitioner must meet the threshold requirement of demonstrating that there is a “reasonable likelihood” that the petitioner would prevail as to at least one of the claims challenged. Accordingly, under 35 U.S.C. § 312(a)(3), the Petition must identify “with particularity … the evidence that supports the grounds for the challenge to each claim.” As stressed by the Federal Circuit:

"It is of the utmost importance that petitioners in the IPR proceedings adhere to the requirement that the initial Petition identify with particularity the evidence that supports the grounds for the challenge to each claim. . . . [T]he expedited nature of IPRs bring with it an obligation for petitioners to make their case in their Petition to institute.”

Wasica Finance GmbH v. Continental Automotive Systems, Inc., 853 F.3d 1272, 1286−87 (Fed. Cir. 2017).

Therefore, it is the burden of the Petitioner to identify in the Petition that the skilled artisan would have had a reasonable expectation of success in achieving the claimed invention by combining references as proposed in the Petition. “Failure to prove the matter as required ... means that the party with the burden of persuasion loses on that point—thus, if the fact trier of the issue is left uncertain, the party with the burden [the petitioner] loses.” Dynamic Drinkware, LLC v. Nat'l Graphics, Inc., 800 F.3d 1375, 1378-79 (Fed. Cir. 2015)

For Patent Owners

Importantly, the burden of proving a reasonable expectation of success is on the Petitioner and never shifts to the Patent Owner. As a result, it is not the burden of the Patent Owner to demonstrate that the proposed combination would not work.

As a result, a Patent Owner can reasonably expect to win an IPR if the Petition fails to address the reasonable expectation of success requirement. For example, in Juniper Networks, Inc. v Correct Transmission, LLC, IPR2021-00682, the Board observed that the “Petitioner [Juniper] leaps silently over the requirement to evidence a reasonable expectation of success to establish obviousness” and, as a result, “[found] Petitioner’s alleged evidence of the requisite reasonable expectation of success fails to meet its evidentiary burden.” Accordingly, the reasonable expectation of success must be specifically addressed by Petitioner’s expert and not simply assumed.

In addition, it can be helpful for the Patent Owner’s expert to explain why there is not a reasonable expectation of success. As the Federal Circuit states, “[w]hether the prior art discloses a claim limitation, whether a skilled artisan would have been motivated to modify or combine teachings in the prior art, and whether she would have had a reasonable expectation of success in doing so are questions of fact.” (Univ. of Strathclyde v. Clear-Vu Lighting LLC, 17 F.4th 155, 160 (Fed. Cir. 2021)) (emphasis added). Further, the Federal Circuit has repeatedly held that “[i]t is within the discretion of the trier of fact to give each item of evidence such weight as it feels appropriate.” (Yorkey v. Diab, 601 F.3d 1279, 1284 (Fed. Cir. 2010)). Specifically, in the case of an IPR, where the Board is the trier of fact, the Federal Circuit held that “[t]he Board was within its discretion to weigh the credibility of expert testimony .”(Shoes by Firebug LLC v. Stride Rite Children's Grp., LLC, 962 F.3d 1362, 1372 (Fed. Cir. 2020)). Therefore, if the Patent Owner adduces expert testimony about the likelihood of success that contradicts that of the Petitioners expert, the Board as the trier of fact, has to weigh the credibility of the expert testimony to determine if the Petitioner has met their burden. In doing so, the Patent Owner increases the likelihood that the trier of fact may find that a reasonable likelihood of success has not been shown.

For Petitioners

As the Federal Circuit explains, “it [is], at all times, [petitioner’s] burden to show that the claims would have been obvious, including that a skilled artisan would have had a reasonable expectation of success in achieving the claimed invention (Eli Lilly & Co. v. Teva Pharm. Int'l GmbH, 8 F.4th 1331, 1348 (Fed. Cir. 2021)). Therefore, it is critical that the expert declaration that is submitted in support of the Petition expressly address the reasonable expectation of success in achieving the claimed invention when combining references under 35 U.S.C. §103. Omitting these elements from the evidentiary record cannot be subsequently corrected by attorney argument because “[w]hether a person of ordinary skill in the art would have been motivated to modify or combine teachings in the prior art, and whether he would have had a reasonable expectation of success, are questions of fact.” (In re Stepan Co., 868 F.3d 1342, 1346 (Fed. Cir. 2017). As a result, it is crucial that the expert declaration submitted in support of the Petition explicitly addresses the reasonable expectation of success in achieving the claimed invention by combining the references when alleging that the challenged patent is invalid under 35 U.S.C. §103.

Neglecting to include these elements in the evidence cannot be rectified solely through attorney argument because “Attorney argument is no substitute for evidence.” (Enzo Biochem v. Gen-Probe, Inc., 424 F.3d 1276, 1284, (Fed. Circ. 2005). In fact, the Federal Circuit holds that “a party’s "unsworn attorney argument . . . is not evidence" and thus cannot rebut record evidence.” (Wasica Fin. GmbH v. Cont'l Auto. Sys., 853 F.3d 1272, 1284-85 (Fed. Cir. 2017).  

Therefore, in order for a Petitioner to meet its burden under 35 U.S.C. §103, the Expert declaration submitted with the Petition must provide explanations why an ordinarily skilled artisan would have (i) been motivated to combine or modify the teachings in the prior art, and (ii) that had a reasonable expectation of success in doing so. Failing to address the reasonable expectation requirement in the expert declaration will likely result in the PTAB finding that the Petitioner has failed to meet its burden in establishing that the patent claims are invalid under 35 U.S.C. §103.