Amgen Inc. v. Sanofi, 987 F.3d 1080

The patents (U.S. Pat. Nos. 8,829,165 and 8,859,741) claim monoclonal antibodies that bind specific PCSK9 residues and block PCSK9 binding to LDLR to lower LDL cholesterol; claims are defined functionally (binding particular residues and blocking activity).
The specification discloses 26 antibody sequences (including 21B12/evolocumab/Repatha) and 3D structures for two antibodies, but examples bind a narrow subset of the claimed residues.
Amgen sued Sanofi for infringement; after a prior remand on enablement/written description issues, a jury found claims enabled, but the district court granted JMOL that claims 19 and 29 of the ’165 patent and claim 7 of the ’741 patent lack enablement.
The district court applied the Wands factors and concluded the claims’ broad functional scope, the unpredictability of antibody structure–function relationships, and the limited guidance in the specification meant practicing the full claim scope would require undue experimentation.
On appeal, the Federal Circuit affirmed: the asserted functional genus claims were not enabled because obtaining embodiments across the full claim scope would require substantial, nonroutine trial-and-error.

Issue	Amgen's Argument	Sanofi's Argument	Held
Whether the asserted claims (’165 claims 19, 29; ’741 claim 7) are enabled under 35 U.S.C. § 112	The specification provides a "roadmap": anchor antibodies, examples, conservative substitutions, and routine screening permit one skilled in the art to make any claimed antibody without undue experimentation	Claims cover millions of candidate antibodies; antibody discovery is unpredictable; specification lacks sufficient guidance so identifying functional embodiments requires excessive trial-and-error	Affirmed JMOL: claims invalid for lack of enablement — undue experimentation required to practice full functional claim scope
Whether the decision conflicts with In re Wands precedent	Argued the ruling improperly departs from Wands, which found antibody claims enabled where hybridoma methods sufficed	Argued Wands is fact-specific; here the combination of broad functional claims, narrow examples, and unpredictability distinguishes this case	Court held no conflict: Wands remains valid; facts here align with later cases (Wyeth, Enzo, Idenix) finding lack of enablement

In re Wands, 858 F.2d 731 (Fed. Cir.) (establishes multi-factor test for undue experimentation)
Wyeth & Cordis Corp. v. Abbott Laboratories, 720 F.3d 1380 (Fed. Cir.) (broad functional claims held not enabled where many candidates require screening)
Enzo Life Scis., Inc. v. Roche Molecular Sys., Inc., 928 F.3d 1340 (Fed. Cir.) (specification failed to teach which embodiments would meet functional requirements)
Idenix Pharms. LLC v. Gilead Scis. Inc., 941 F.3d 1149 (Fed. Cir.) (broad functional genus required undue experimentation to find efficacious members)
McRO, Inc. v. Bandai Namco Games Am. Inc., 959 F.3d 1091 (Fed. Cir.) (enablement requires concrete identification of unenabled embodiments when claiming broad scope)
Alcon Research Ltd. v. Barr Labs., Inc., 745 F.3d 1180 (Fed. Cir.) (enablement is a question of law based on underlying factual findings)
Crown Operations Int’l v. Solutia Inc., 289 F.3d 1367 (Fed. Cir.) (specification must enable commensurate with claim scope)
AK Steel Corp. v. Sollac, 344 F.3d 1234 (Fed. Cir.) (range claims require reasonable enablement across claimed breadth)