Presented by John Goodhue
A unanimous Supreme Court, in an opinion by Justice Gorsuch, held that Amgen's patents were invalid for lack of enablement. Amgen claimed an entire genus of antibodies defined by their function — binding to specific residues on PCSK9 and blocking it — while disclosing only 26 antibodies by amino-acid sequence. Section 112 requires the specification to enable the full scope of what is claimed; the more a patent claims, the more it must enable. Amgen's "roadmap" and "conservative substitution" methods amounted to little more than research assignments, leaving skilled artisans to trial-and-error across a vast genus. The Court affirmed the Federal Circuit.
Amgen v. Sanofi, decided May 18th, 2023. A unanimous Supreme Court, in an opinion by Justice Gorsuch, affirmed the Federal Circuit and held that Amgen's antibody patents were invalid for lack of enablement. Under section 112(a), the specification must enable a person skilled in the art to make and use the full scope of what the claims cover — and Amgen's functional claims to an entire genus of antibodies did not. Here's the brief.
Amgen and Sanofi each developed an antibody drug that lowers LDL cholesterol by inhibiting a protein called PCSK9. PCSK9 binds to and degrades LDL receptors — the proteins that clear cholesterol from the bloodstream. Block PCSK9, and more receptors survive to do that work. In 2011, Amgen patented the specific antibody in its drug, Repatha, by its amino-acid sequence; Sanofi did the same for the antibody in Praluent. Those patents are not at issue.
At issue are two later patents Amgen obtained in 2014 — claims 19 and 29 of the '165 patent and claim 7 of the '741 patent. There, Amgen claimed no particular antibody. It claimed an entire genus, defined by what the antibodies do.
The specification identified 26 antibodies by sequence, but the claims reached potentially millions. Amgen sued Sanofi for infringement; Sanofi replied that the claims were invalid for lack of enablement. The district court and the Federal Circuit both sided with Sanofi.
The question was whether to disturb that judgment — whether Amgen's specification enabled the full scope of its functional claims.
Section 112(a) requires disclosure full, clear, concise, and exact enough to enable any person skilled in the art to make and use the invention. The Court traced the requirement to the Patent Act of 1790 and to the constitutional patent bargain: a limited monopoly in exchange for a disclosure that lets the public practice the invention once the term expires. And it read that requirement against three of its own precedents — Morse, the Incandescent Lamp case, and Holland Furniture — each involving a patentee who claimed far more than the specification taught others to make.
The Court held, unanimously, that Amgen failed to enable all that it claimed.
Its reasoning began with that history. In Morse, the Court struck down a claim to every use of electromagnetism to print characters at a distance, because Morse had not shown how to make and use them all. In the Incandescent Lamp case, Sawyer and Man claimed every fibrous or textile material for a lamp conductor, but only painstaking experimentation revealed that bamboo — Edison's discovery — actually worked. And in Holland Furniture, Perkins claimed all starch glues that performed like animal glue, described by function alone. The lesson the Court drew:
Amgen's claims, the Court said, bore more than a passing resemblance to those old ones: it sought to monopolize an entire class of antibodies defined by function while describing only 26. Amgen answered that its "roadmap" and "conservative substitution" methods let scientists make the rest. The Court disagreed.
Those methods, the Court explained, were step-by-step invitations to trial and error across the genus. That, the Court said, is not enablement; it is closer to a hunting license. Borrowing an amicus analogy, the Court likened the claims to disclosing 26 working combinations of a hundred-tumbler lock while claiming every combination that opens it. The Court added two calibrations. A specification need not describe every embodiment — disclosing a quality common to the class can suffice, and reasonable experimentation is always allowed. And there is a single enablement standard for all inventions; but the broader the claim, the more that standard demands.
Amgen is the Court's most consequential enablement decision in a century, and it resolved the question by reaffirming continuity rather than announcing anything new. The functional genus claim — common in antibody and biotechnology patenting — is measured by the same rule the Court applied to telegraphs, lamps, and glue: the disclosure must reach as far as the claim. The Court rejected the argument that this test would chill breakthrough invention, calling the balance between incentive and disclosure a judgment for Congress. The case stands for a single proposition: claim scope and enablement rise together.
Amgen v. Sanofi, 598 U.S. 594, decided May 18th, 2023. I'm John Goodhue. Thanks for watching.
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