Did Teva Alter The Standard For Invalidating A Patent For Indefiniteness?

As discussed in the concurrent article, prior to the Supreme Court's decision in Teva Pharmaceuticals v. Sandoz, Inc., 574 U.S. ___ , No. 13-854, slip op. (2015), the Court of Appeals for the Federal Circuit ("Federal Circuit") declined to give deference to district court judges' findings of subsidiary facts made during claim construction, as required by Federal Rule of Civil Procedure § 52(a)(6). Although the parties' dispute in Teva was whether the claims in Teva's patent were indefinite under 35 U.S.C. § 112, second paragraph,¹ the question before the Court was whether the Federal Circuit employed the proper standard of review of a district court's factual findings during claim construction.² The Court did not consider the underlying issue of indefiniteness, but rather it vacated the Federal Circuit's decision and remanded with explicit instructions on how to apply the appropriate standard of review.