Federal Circuit Clarifies Scope of IPR Estoppel, Reversing Prior Shaw Decision

Feb 23, 2022

Reading Time : 2 min

Section 315(e)(2) sets forth the scope of IPR estoppel in civil litigation. Under that Section, the petitioner in an IPR that results in a final written decision “may not assert … any [invalidity] ground that the petitioner raised or reasonably could have raised” during that IPR. In Shaw, the Federal Circuit held that because an IPR does not begin until it is instituted, only those grounds on which the Patent Trial and Appeal Board (PTAB) institutes review meet the “raised or reasonably could have been raised” standard, and therefore, only those grounds that actually get reviewed during the IPR were subject to estoppel. 

However, because Shaw only involved a ground that was raised in the petition, but was not instituted by the PTAB, district courts split on whether that decision extended to grounds that were not included in the petition.

In California Institute of Technology v. Broadcom Ltd, a panel of the Federal Circuit was asked to clarify the scope of IPR estoppel. In that case, multiple accused infringers filed petitions for IPRs that were instituted, but ultimately unsuccessful. Failing to invalidate the claims through IPRs, the accused infringers raised new prior art invalidity grounds in the district court that were not presented to the PTAB. The district court held the accused infringers were estopped from raising those grounds because they were aware of the prior art references when the IPR petitions were filed, and could have raised them in the petitions.

The Federal Circuit agreed, holding that IPR estoppel applies to all grounds that a petitioner raised or reasonably could have raised at the time the petition was filed. In so doing, the court reversed its decision in Shaw. As the court explained, at the time Shaw was decided, the PTAB would often institute IPRs on fewer than all grounds raised in an IPR (as in Shaw). Thus, it made sense at the time that a petitioner should not be barred from later litigating grounds that were not reviewed in an IPR. After Shaw, however, the Supreme Court’s SAS Institute decision made clear that the PTAB’s institution authority did not permit partial institution. Rather, the PTAB was required to institute on all grounds or deny institution. Under SAS Institute, it is the petition that defines the IPR and any resulting estoppel.

The panel also clarified its authority to overrule a prior decision of the Federal Circuit without en banc activity. While acknowledging that the Supreme Court’s decision in SAS Institute did not explicitly overrule Shaw, the panel explained that the reasoning in Shaw rests on an assumption that the Supreme Court rejected. Thus, SAS Institute sufficiently undercut the theory or reasoning underlying Shaw, such that the rulings were irreconcilable, which permitted the panel in this case to overrule the Shaw panel’s decision. 

Practice Tip: Because the Federal Circuit has now clarified that IPR estoppel extends to all grounds that could have been raised in an IPR petition that results in a final written decision, petitioners should consider all defenses, including those that cannot be raised at the PTAB (e.g., evidence of prior use, Section 112 defenses), when evaluating whether to petition for IPR.

Share This Insight

Previous Entries

IP Newsflash

December 3, 2025

The Federal Circuit recently held that a patentee acted as its own lexicographer to define a claim term even though it did not explicitly define the term. Rather, because the patentee consistently and clearly used two terms interchangeably to describe the same structural feature and did so in all of the embodiments in which the feature appeared, the patentee impliedly gave the term its own, unique definition.

...

Read More

IP Newsflash

December 2, 2025

The Federal Circuit recently held an asserted patent was not entitled to its priority date because the priority application lacked written description support for the asserted claims. In so doing, the court explained that broad disclosures that do not provide reasonably specific support for narrower claims do not meet the written description requirement. The court also considered whether the inventor’s testimony showed they possessed the full scope of the claimed genus at the priority date or whether it was more likely the inventors first became aware of the claimed embodiments from public disclosures of the accused product.

...

Read More

IP Newsflash

December 1, 2025

In a Hatch-Waxman case, the District of Delaware denied a motion for summary judgment seeking to apply the ANDA filing date as the date of the hypothetical negotiation used to calculate reasonable royalty damages. Instead, the court determined that the appropriate date to use for the hypothetical negotiation is the launch date.

...

Read More

IP Newsflash

November 17,2025

The district of Delaware recently denied a defendant’s partial motion to dismiss pre-suit willful infringement from the litigation, finding instead that the allegations taken as a whole were sufficient to support pre-suit willfulness at the pleading stage. Specifically, the court found that the allegations as to the defendant’s involvement in a related foreign opposition proceeding and participation in the relevant industry were accompanied by detailed factual support that sufficiently pleaded willful infringement for the pre-suit period.

...

Read More

© 2025 Akin Gump Strauss Hauer & Feld LLP. All rights reserved. Attorney advertising. This document is distributed for informational use only; it does not constitute legal advice and should not be used as such. Prior results do not guarantee a similar outcome. Akin is the practicing name of Akin Gump LLP, a New York limited liability partnership authorized and regulated by the Solicitors Regulation Authority under number 267321. A list of the partners is available for inspection at Eighth Floor, Ten Bishops Square, London E1 6EG. For more information about Akin Gump LLP, Akin Gump Strauss Hauer & Feld LLP and other associated entities under which the Akin Gump network operates worldwide, please see our Legal Notices page.