by Dennis Crouch
In their forthcoming article, Professors Dmitry Karshtedt, Mark A. Lemley & Sean B. Seymore argue that the Federal Circuit has improperly and unduly limited the ability of chemical and biotech innovators to obtain genus claims — i.e., claims that cover “not just one specific chemical but a group of related chemicals.” The Death of the Genus Claim, 35 Harv. J.L. & Tech. (forthcoming 2021). Now, the trio (along with others) have taken their prior work and converted it to an amicus brief supporting en banc review in the pending case of Amgen Inc. v. Sanofi, Docket No. 20-01074 (Fed. Cir. Oct 24, 2019). Amgen v. Sanofi – Lemley Brief.
The focus of the case is on “genus claims” where the genus is defined by functional limitations. Here, the patent covers antibodies that bind to a certain protein-molecule [PCSK9] in a certain way [to block LDRL binding]. However, the claim does not affirmatively spell-out the structure of the claim.
An isolated monoclonal antibody [that] binds to [one of the residues of PCSK9] and … blocks binding of PCSK9 to LDRL.
In its decision, the Federal Circuit held that it would be very difficult for a patentee to enable such a claim because there are thousands (or potentially millions) of molecules that might reasonably fit this definition. It would take undue experimentation to test each and every one of these myriad prospects. Karshtedt, Lemley, and Seymore argue that the Federal Circuit’s approach here is problematic:
That is an impossible burden, and it is not one the law imposed until recently. It represents “a categorical shift in thinking away from teaching the PHOSITA and towards a precise delineation of the boundaries of the claim.”
Brief (quoting their article). In its decision, the court makes clear that it is still technically possible to enable such a claim, but effectively admits that it is not practically possible.
While functional claim limitations are not necessarily precluded in claims that meet the enablement requirement, such limitations pose high hurdles in fulfilling the enablement requirement for claims with broad functional language.
Functional Claim Language: The decision briefing focuses on chemistry and biotech, but the truth is that functional claim limitations are most often found in claims directed to mechanical, electronic, and software fields. These functional claims – to the extent they encompass thousands (or potentially millions) of embodiments – are equally susceptible to the transformed approach. For many years, these two arenas have been treated differently for enablement purposes — with courts often classifying innovations as either within the predictable or unpredictable arts. However, Amgen also shows substantial crossover. In other words, Amgen is generally another attack on claims defined by functional limits.
On point, the Amgen court repeatedly cites and references the enablement discussion found in the lip synchronization software case of McRO, Inc. v. Bandai Namco Games Am. Inc., 959 F.3d 1091 (Fed. Cir. 2020). Amgen focused particularly on FN2 from that case:
In cases involving claims that state certain structural requirements and also require performance of some function (e.g., efficacy for a certain purpose), we have explained that undue experimentation can include undue experimentation in identifying, from among the many concretely identified compounds that meet the structural requirements, the compounds that satisfy the functional requirement.
Id. Two additional amicus briefs have been filed in the case:
- Amgen v. Sanofi – GSK Brief (“The Patent Act allows Genus Claiming and does not require ‘Full Scope’ enablement.”, etc.)
- Amgen v. Sanofi – Biogen BMS Corning Brief (The jury’s role in determining enablement should be restored, etc.).