Processing All Things Federal Circuit
April 18, 2023 - Last Week in the Federal Circuit

Last Week In The Federal Circuit (April 10 – April 14): IPR Statutory Estoppel, In Two Acts

play station controllers

If the scope of the IPR estoppel statute has been keeping you up at night, our latest case of the (recent) week might help you sleep a little better because it provides clarity on two aspects of the statute’s reach.

Case of the (recent) week: Ironburg Inventions Ltd. v. Valve Corporation, No. 21-2296

Panel: Lourie, Clevenger, and Stark, with Judge Stark writing the majority opinion

You should read this case if: you have a case involving the scope of IPR estoppel

Ironburg and Valve have had a long-running patent dispute about video game controllers. After Ironburg sued Valve, Valve challenged Ironburg’s patent claims in an IPR. The Board instituted review on some, but not all, of the grounds in Valve’s petition and cancelled some of the challenged claims. Although the Supreme Court later rejected the Board’s partial institution practice in SAS Institute Inc. v. Iancu while Valve’s IPR case was still pending, Valve did not request a remand for the Board to reconsider the partial institution.

Meanwhile, the parties proceeded with litigation in district court. Before trial, Ironburg successfully moved for an order applying IPR estoppel under 35 U.S.C. § 315(e)(2) to: (1) the non-instituted grounds from the IPR; and (2) additional invalidity grounds Valve discovered after it filed its IPR petition. After a jury returned a willful infringement verdict for Ironburg, Valve appealed the application of IPR estoppel (along with several other issues).

The Federal Circuit agreed with the district court that estoppel applies to the non-instituted grounds. The Court explained that statutory estoppel applies to “any ground that the petitioner raised or reasonably could have raised during th[e] inter partes review.” The focus of that inquiry is on “the petition, not the institution decision.” Because the non-instituted grounds were in the petition, “[t]hey were ‘raised during the inter partes review’” sufficiently to trigger preclusion.

But Valve had more success on its challenge to the application of estoppel to the later-discovered grounds that were not included in Valve’s IPR petition. The Court held that “the district court improperly placed the burden of proof on Valve, to show that it could not ‘reasonably have raised’” those grounds in the petition. But “the burden of proving, by a preponderance of the evidence, that a skilled searcher exercising reasonable diligence would have identified an invalidity ground rests on the patent holder.” The Court explained that this burden allocation was consistent with “the general practice that a party asserting an affirmative defense bears the burden to prove it.” The Court vacated and remanded for the district court to determine whether Ironburg can meet that burden.


Precedential opinions: 8

Non-precedential opinions: 13

Rule 36: 6

Longest pending case from argument: Sanderling Management Ltd. v. Snap Inc., No. 21-2173 (251 days) 

Shortest (non-Rule 36) pending case from argument: BlueCatBio MA Inc. v. Yantai AusBio Laboratories Co., Ltd., No. 22-1450 (9 days)