Publication Date

Fall 2022

Document Type



A 2020 law review article entitled The Death of the Genus Claim (“Death”) purports to document a dramatic shift in the Federal Circuit’s interpretation of 35 U.S.C. 112(a)’s enablement and written description requirements, particularly as applied to chemical genus claims. According to the authors of Death, it has become nearly impossible to obtain a chemical genus claim that will be upheld as valid in the face of a challenge for overbreadth under Section 112(a). Death was cited extensively in Amgens’s successful petition for certiorari in Amgen v. Sanofi, a case asking the Supreme Court to overturn the Federal Circuit’s decision finding Amgen’s claims reciting genuses of monoclonal antibodies to be invalid for lack of enablement. Death raise important issues for pharmaceutical innovation, a number of which I address in this first installment (“Part I”) of a two-part article. I begin by providing some excerpts from Judge Lourie’s concurrence in the Federal Circuit’s denial of en banc rehearing of Amgen v. Sanofi, in which he refutes the key arguments raised in Death and by Amgen. I then take a deep dive, exploring what in particular we mean when we refer to a patent claim as a “chemical genus claim,” an important term that is subject to different interpretations. Those who use the term, including the authors of Death, often do so without explicitly defining it, which can result in some lack of clarity. In the remainder of this Part I, I reanalyze the judicial decisions upon which Death bases its claim, and explain why, in my view, the article does not actually substantiate its claim of a marked shift in the Federal Circuit’s interpretation and application of 112(a).

Publication Title

Biotechnology Law Report