It has been close to three years since the PTAB first exercised its discretion to decline institution of inter partes review grounds it found to be “redundant” of grounds on which it instituted trial. See CBM2012-00003, No. 7 at 2 (P.T.A.B. Oct. 25, 2012). Since then, the PTAB has routinely been exercising its discretion in this way to take into account “efficient administration of the Office, and the ability of the Office to timely complete proceedings.” See C.F.R. § 42.1(b).

But what happens if the petitioner loses on the ground that was instituted? Will the petitioner be estopped from raising the “redundant” ground that was never considered on the merits? Last week, in a (non)-Institution Decision, the PTAB addressed that issue as applied to patent office proceedings. In Apotex Inc. v. Wyeth, the PTAB determined that Petitioner Apotex was not estopped under 35 U.S.C. § 315(e)(1). Apotex Inc. v. Wyeth LLC, IPR2015-00873, No. 8 (P.T.A.B. September 16, 2015).

The estoppel provision of 35 U.S.C. § 315(e)(1), which relates to proceedings before the Office, applies only to grounds that the petitioners “raised or reasonably could have raised during [the] inter partes review.” The PTAB reasoned that the “redundant” ground was not raised “during” the first inter partes review since it was raised only during the preliminary proceeding but not made a part of the instituted trail. See IPR2015-00873, No. 8 at 8-9. Nor was the ground one that “reasonably could have been raised during” the review, because once denied, the Board’s decision on institution prevented Apotex from raising that ground during trial. Id. at 9. Thus, the PTAB found that estoppel under 35 U.S.C. § 315(e)(1) does not bar Apotex from maintaining a proceeding before the Office on the ground.

Although Apotex was successful on the estoppel issue, it ultimately failed in getting the trial instituted because it was not able to establish a reasonable likelihood that it would prevail on the merits.

The estoppel provision of 35 U.S.C. § 315(e)(2), which relates to civil actions and other (non- Office) proceedings, is worded similarly to the provision relates to Office proceedings. It remains to be seen how district courts and the Federal Circuit will apply this provision when a losing IPR petitioner attempts to raise a “redundant” non-instituted ground in a civil action. Will the losing petitioner get second bite at the invalidity apple in court?