Facts of the Case

Provided by Oyez

Amgen owns two patents that describe cholesterol-lowering drugs that share a common written description. In 2014, Amgen filed suit against Sanofi alleging infringement of multiple patents, including the two at issue in this case. Among the jury’s conclusions in that case was that the patents were not invalid for lack of written description and enablement.


To satisfy the written description requirement, a patent specification must describe the claimed invention in sufficient detail that a “skilled artisan” can reasonably conclude that the inventor had possession of the claimed invention. To satisfy the enablement requirement, a patent specification must contain sufficient information that a “skilled artisan” would be enabled to make and use the claimed invention.


The U.S. Court for the Federal Circuit reversed and remanded, finding the jury instructions regarding enablement were erroneous.


On remand, the court ruled in favor of Sanofi on the issue of lack of enablement and for Amgen on the issue of lack of written description. Amgen appealed, and the Federal Circuit affirmed the district court’s determination that the asserted claims were invalid for lack of enablement.


  1. Do Amgen’s two patents satisfy the Patent Act’s enablement clause—that is, describing the invention with sufficient particularity that would enable a “skilled artisan” to “make and use” the claimed invention?


  1. Amgen’s two patent applications—purporting to cover all antibodies that bind and block the PCSK9 receptor involved in LDL cholesterol metabolism—fail to satisfy the Patent Act’s enablement clause. Justice Neil Gorsuch authored the unanimous opinion of the Court affirming the judgment below.

    It is well established that the enablement requirement means that if a patent claims an entire class of process, machines, manufactures, or compositions of matter, its specification must enable a person skilled in the art to make and use the entire class. While the specification may call for a reasonable amount of experimentation to make and use a claimed invention, it must not be too broad. Amgen’s specification fails to enable all that it has claimed, even allowing for a reasonable degree of experimentation. It described 26 antibodies by their amino acid sequences, but it claims to monopolize an entire class of antibodies not described. Thus, its claim is too broad.