On January 20, 2015, the Supreme Court issued its decision in Teva Pharmaceuticals USA, Inc. v. Sandoz, Inc. This case concerned whether a district court’s factual finding in support of its construction of a patent claim may be reviewed de novo--the standard applied by the Federal Circuit in this case--or must instead be reviewed only for clear error, in keeping with Federal Rule of Civil Procedure 52(a). -- In an opinion delivered by Justice Breyer, the Court held by a vote of 7-2 that when reviewing a district court’s resolution of subsidiary factual matters made in the course of its construction of a patent claim, the Federal Circuit must apply a “clear error,” not a de novo, standard of review. The judgment of the United States Court of Appeals for the Federal Circuit was vacated and the case remanded for further proceedings. -- Justice Breyer’s opinion was joined by Chief Justice Roberts and Justices Scalia, Kennedy, Ginsburg, Sotomayor, and Kagan. Justice Thomas filed a dissenting opinion, which Justice Alito joined. -- To discuss the case, we have Prof. Kristen Osenga, who is a Professor of Law at the University of Richmond School of Law.