Takeaways
- Estoppel certification in reexamination prevents relitigation of resolved issues.
- Estoppel’s “reasonably could have raised” standard requires exhaustive prior art searching and strategic planning.
As we discussed in our March article, with the recent changes to Patent Trial and Appeal Board (PTAB) procedures for institution of post-grant trials, it is likely that reexamination requests will factor more heavily in post-grant challenge considerations. Whether considering a parallel or a subsequent reexamination of a patent in concluded PTAB challenges, the estoppel provision of 35 U.S.C. § 315(e)(1) must be considered.
Statutory Estoppel Provisions
The estoppel provision prevents a petitioner, real party in interest, or privy of the petitioner from requesting or maintaining a proceeding before the USPTO (including ex parte reexamination) with respect to any claim that was subject to a final written decision in a PTAB proceeding on any ground that was raised or reasonably could have been raised during that PTAB proceeding. The intent of the estoppel provision is to balance the efficiency of administrative proceedings before the Office and to prevent patent owner harassment. What is estopped is evolving law, with several Courts weighing in over the last half decade. See, e.g., Article 1; Article 2; Article 3.
Reexamination Certification
Reexamination requesters must certify, under 37 C.F.R. 1.510(b)(6), that the statutory estoppel provisions of 35 U.S.C. § 315(e)(1) or 35 U.S.C. § 325(e)(1) do not prohibit the requester from filing the ex parte reexamination request. Notably, statutory estoppel attaches only to the patent claims that receive a final written decision in a PTAB proceeding. Unpatentability grounds denied institution in a PTAB proceeding do not trigger statutory estoppel. The certification applies to all claims challenged in the reexamination request. A defective or omitted certification may lead to a dismissal or denial of the request. Moreover, the estoppel certification requirement can create a significant barrier for parties who have previously challenged a patent in an IPR from subsequently requesting reexamination, even on different grounds or different prior art. Certification requires requesters to affirm that they are not attempting to relitigate issues resolved in prior USPTO proceedings.
Anonymous Reexamination Request Certification
Reexamination rules do not require ex parte reexamination requesters to identify themselves upon the filing of the request under 35 U.S.C. §302. The certification requirement of 37 C.F.R. §1.510(b)(6), coupled with a party’s 37 C.F.R. §11.18 certification obligations when transacting business before the Office, are considered by the Office to be sufficient to ensure compliance with the statutory estoppel requirements. A real party in interest that wishes to remain anonymous when filing a request for reexamination under 37 C.F.R. § 1.510 can do so by utilizing the services of a registered practitioner. In such an instance, the registered practitioner submitting a request for reexamination on behalf of the real party in interest would be certifying that the real party in interest was not estopped from filing the request. Conversely, an individual filing a request for reexamination under 37 C.F.R. §1.510 on behalf of the individual cannot remain anonymous, as the individual is required to sign the reexamination request document that includes the 37 C.F.R. §1.510(b)(6) certification.
Strategic Considerations
The estoppel provision under 35 U.S.C. § 315(e)(1) or 35 U.S.C. § 325(e)(1) and the related certification requirements 37 C.F.R. §1.510(b)(6) create critical guardrails for efficient administrative proceedings at the USPTO. The interplay between statutory estoppel and reexamination certification demands careful navigation by experienced practitioners. Petitioners and requesters must conduct exhaustive prior art searches prior to initiating administrative challenges, and must analyze prior challenge outcomes before requesting reexamination. While estoppel limits redundant challenges, its claim-specific application and exceptions for non-instituted grounds provide flexibility and options for requesters. And although the authors have not seen a challenge that new prior art overcomes the estoppel, as has played out in the district courts and the Federal Circuit, it remains to be seen what the USPTO will do when that challenge is brought. For example, will proving evidence that a thorough first search was performed pre-PTAB trial followed by a thorough second search post-PTAB trial with newly discovered art be enough to overcome the estoppel?
In these shifting sands of PTAB jurisprudence, stakeholders must stay attuned to developments in estoppel’s “reasonably could have raised” standard and its implications for post-grant administrative proceeding challenges.
