By Miriam Swedlow

Despite overruling the Federal Circuit’s prior practice of reviewing all aspects of patent claim construction de novo, the Supreme Court’s ruling in Teva Pharmaceuticals USA, Inc. v. Sandoz, Inc. has not dramatically changed the standard of review for patent claims. Instead, it imparts a sub-category of analysis in cases where the district court relies upon extrinsic evidence to clarify ambiguous or complicated facts needed for proper claim construction. The court first considers whether the district court relied upon extrinsic evidence and if so, whether it needed to in order to properly construe the claim. As predicted by the Supreme Court, only a small number of cases have required clear error review of fact finding in the months following the Teva decision. Ultimately, clear error review of fact-finding from extrinsic evidence simply adds one step prior to the traditional de novo review applied to patent claim construction.  Continue reading →