SCOTUS Changes The Rules For Patent Claim Construction On Appeal

For almost 100 years, Canadian Courts have consistently held that the interpretation of a patent claim is a question of law. In almost every context, questions of law are reviewed on a de novo basis, without deference. As the Canadian courts of appeal routinely describe claim construction purely as a "question of law,"¹ in practice it is unclear whether the factual findings of the trial judge are afforded deference in claim construction (for example, in the assessment of the common general knowledge that informs the meaning of claim terms). In light of the United States Supreme Court opinion in Teva Pharmaceuticals USA, Inc. v. Sandoz, Inc.² and recent developments in Canadian law, this principle is ripe for reconsideration in Canada.