Winning The Battle But Losing The War? - New Considerations For File Wrapper Estoppel

The newness of inter partes reviews (IPR) means that the process is potentially beset with estoppel minefields in as yet untested legal waters. A potential good-news, bad-news story would be a patent owner granted denial of a patent challenger's IPR petition at the Patent Trial and Appeal Board (PTAB), but later faced with a reduced scope of claim coverage because of statements made in the preliminary response or otherwise in the proceeding.

In an IPR petition, the petitioner sets forth grounds for challenging the validity of the patent claims over prior art. 35 U.S.C. § 312(a). The PTAB reviews the petition, as well as the owner's optional preliminary response and issues a decision whether there is a “reasonable likelihood that petitioner would prevail” on one or more of the petition grounds. 35 U.S.C. § 314(a). If so, the IPR is instituted and the trial proceeds until settlement or a final written decision on the validity of the claims is reached.

Much has been written about the IPR's estoppel provision for the petitioner (or the “real party in interest or privy of the petitioner”), but relatively little regarding the effect of statements by the patent owner where the IPR is not instituted. As set forth in 35 U.S.C. § 315(e), the IPR's estoppel provision only addresses the attachment of estoppel to the petitioner when a final written decision under 35 U.S.C. § 318(a) is rendered, so as to preclude the...