IPR Estoppel in Action

IPR Estoppel in Action, PTAB Litigation Blog

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Recently, District Court Judge Thomas S. Zilly in the Western District of Washington granted Ironburg Inventions Ltd.’s (“Ironburg”) motion for inter partes review (“IPR”) estoppelpursuant to 35 U.S.C. § 315(e)(2), which precludes Valve Corporation (“Valve”) from arguing non-petitioned grounds of invalidity of asserted patent claims in U.S. Patent No. 8,641,525 B2 in Ironburg Inventions Ltd. v. Valve Corporation, No. 2:17-CV-01182.  See D.I. 544; 545.

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