Idenix v. Gilead: The enablement and written description limits of a genus claim

In Idenix Pharms. LLC v. Gilead Sci. Inc., 941 F.3d 1149 (Fed. Cir. 2019), the Federal Circuit affirmed a judgment of invalidity of a patent claiming methods for treating Hepatitis C virus for, inter alia, lack of enablement. The Supreme Court denied Idenix’s petition for a writ of certiorari, meaning that the Federal Circuit decision stands, and genus claims covering thousands of compounds that were supported by an insufficient number of examples have failed the enablement test not once, but twice. See Wyeth & Cordis Corp. v. Abbott Labs., 720 F.3d 1380 (Fed. Cir. 2013). This case report presents the context surrounding the Federal Circuit’s Idenix decision and the Supreme Court’s decision not to hear the case.