Federal Circuit clarifies scope of IPR Estoppel, resolves split among district courts
Federal Circuit Clarifies Scope Of IPR Estoppel, Resolves Split Among District Courts
By restricting a ‘ground’ to only patents and printed publications, an IPR petitioner may not raise ‘system prior art’ in an IPR petition.
Patent Trial and Appeal Board (PTAB) post-grant validity challenges — for example, inter partes review — are frequent components of a patent litigation strategy for defendants. Challenging the validity of a patent in an IPR does not come without risk, however. If the PTAB institutes trial for the petitioner’s challenge and then finally upholds the validity of the challenged claims in a final written decision, a petitioner is subject to Estoppel. This results in the unsuccessful petitioner being Estopped from challenging the validity of a claim it previously challenged in district court or the International Trade Commission on any ‘ground’ that the petitioner “raised or reasonably could have raised during” the IPR. 35 U.S.C. § 315(e)(2). This statutory Estoppel is meant to prevent a petitioner from re-litigating validity issues that it raised or reasonably could have raised in its IPR petition.
There is uncertainty over the scope of IPR Estoppel based on the meaning of the term ‘ground’ in the IPR statute. In an IPR, a petitioner may challenge claims of a patent "only on a ground that could be raised under section 102 or 103 and only on the basis of prior art consisting of patents or printed publications.” By restricting a ‘ground’ to only patents and printed publications, an IPR petitioner may not raise ‘system prior art’ in an IPR petition. In general, ‘system prior art’ includes a publicly available system (example, a commercial product) that was in public use, on sale, or otherwise accessible before the critical date of the challenged patent. Recently the US Court of Appeals for the Federal Circuit clarified what prior art may be part of a ‘ground’ in an IPR and hence subject to IPR Estoppel. In so doing, the Federal Circuit resolved a split among district courts-even in the same district-over whether IPR Estoppel includes “system prior art”. In Ingenico, the Federal Circuit explained that the issue of whether IPR Estoppel may include system prior art “depends on the proper interpretation of the term ‘ground’ used in 35 U.S.C. § 315(e)(2).” The clarification of the Federal Circuit in Ingenico that IPR Estoppel does not include system prior art preserves important invalidity defenses in district court based on system prior art. The scope of IPR Estoppel has been narrowed by Ingenico to exclude system prior art even if it is substantively identical to prior art that was raised in an unsuccessful IPR. Practitioners should continue to monitor this topic to see how far courts will allow unsuccessful IPR petitioners to reuse IPR prior art presented as system prior art.
