Written Description Requirement Challenges: Federal Circuit Decision Sheds Light On How Expert Testimony Can Help

Earlier this month, in Novartis Pharms. Corp., Inc. v. Accord Healthcare, Inc., et al., No. 2021-1070, the Federal Circuit issued a helpful decision concerning the not-often-discussed written description requirement. The panel specifically addressed whether sufficient written description can exist for claim limitations that are not explicitly or directly disclosed in the specification (including negative claim limitations). This new ruling provides patent owners with a useful guide for successfully navigating similar written description challenges in patent infringement cases. For example, Patent Owners seeking to combat written description requirement challenges should proffer expert witnesses who can clearly articulate how they understand the patent description in relation to the claims and what portions of that description support the same.