Whether a court can refuse to entertain a constitutional, separation-of-powers challenge based on an intervening change of law on the grounds of forfeiture

QUESTIONS PRESENTED While Sanofi’s appeal was pending before the Federal Circuit, the court decided Arthrex, Inc. v. Smith & Nephew, Inc., 941 F.3d 1320 (Fed. Cir. 2019), holding that Administrative Patent Judges (APJs) on the Patent Trial and Appeals Board (PTAB) were appointed in violation of the Appointments Clause, and vacated and remanded the APJs’ final written decision for redetermination by properly appointed APJs. But the Federal Circuit subsequently held that this change in law applies only to parties who raised an Appointments Clause challenge in their opening appellate brief, and refused to apply its new law to all other parties whose appeals were pending when Arthrex was decided. Thus, in the decision below, the Federal Circuit refused to vacate and remand the PTAB’s decisions—issued by judges—because Sanofi had not raised such a challenge in its opening brief, and affirmed the PTAB’s finding that the challenged patents were invalid as obvious. The questions presented are: 1. Whether, in a pending case, a court can refuse to entertain a constitutional, challenge based on an intervening change of law on the grounds of forfeiture. 2. Whether the Federal Circuit’s obviousness holding is an unwarranted expansion of this Court’s decision in KSR International Co. v. Teleflex, Inc., 550 U.S. 398 (2007), and is inconsistent with the Patent Act.