USPTO Guidelines: Amgen is a Nothingburger

by Dennis Crouch
The USPTO has published new examination guidelines regarding the enablement requirement for utility patent applications in light of the Supreme Court’s May 2023 decision in Amgen v. Sanofi , 143 S. Ct. 1243 (2023).  As I explain below, the primary takeaway from the published examination guidelines is that the PTO will continue business as usual — i.e., Amgen did not significantly change the law.  Still, there are, some key points to consider. Notably, the guidelines: (1) provide a reminder that enablement applies to all technology areas, not just biotech; and (2) suggests that the office may increase its assertion of the enablement doctrine against functionally defined claim limitations that are potentially directed to a large number of embodiments.
Background on Amgen v. Sanofi : In its unanimous opinion, the Supreme Court affirmed that Amgen’s broad functional claim was invalid having failed the requirements that claims must be enabled to their full scope, allowing for “a reasonable amount of experimentation.” Amgen . The claim at issue included a key broad functional element — covering all antibodies capable of binding with and disabling a particular enzyme (PCSK9).  Although the Federal Circuit commented negatively on the functional aspect of the claim, the Supreme Court noted that there is no special rule for functional claims.  Still, functional claims can often be suspect on enablement grounds because of their potential breadth that goes well beyond tech disclosed. The result then is a simple rule: broader claims require more detailed disclosure.
If a patent claims an entire class of processes, machines, manufactures, or compositions of matter, the patent’s specification must enable a person skilled in the art to make and use the entire class. . . . The more one claims, the more one must enable.
Id.  To be clear the specification is not required to “describe with particularity how to make and use every single embodiment within a claimed class.” Id .  In fact, I would posit that in most situations it is effectively impossible to describe all potential embodiments covered by a modern comprising-style patent claim. Instead of fully describing every potentiality, the court concluded that the specification must provide enough disclosure to “reliably enable a person skilled in the art to make and use all of what is claimed, not merely a subset” allowing for a reasonable amount of experimentation. Id . The threshold for enablement can often be difficult to ascertain, but here the Supreme Court made clear that Amgen’s specification was more of a research assignment than an enabling disclosure. The Court also noted that whether experimentation is reasonable depends on the context, citing Minerals Separation, Ltd. v. Hyde , 242 U.S. 261 (1916).
Two potential Points of Confusion : The Supreme Court’s analysis in Amgen introduced two potential points of confusion regarding enablement doctrine. First, while citing a litany of its own old precedent on enablement related to technologies like telegraphs and incandescent light, the Court did not explicitly reference leading contemporary Federal Circuit decisions that articulate enablement standards. Most notably, Amgen does not mention In re Wands , 858 F.2d 731 (Fed. Cir. 1988) and its seminal “ Wands factors” that are regularly relied upon by patent examiners and litigants to assess if PHOSITA would need to conduct an unreasonable amount of experimentation in order to make and use the invention. These Wands factors include:

(A) the breadth of the claims;
(B) the nature of the invention;
(C) the state of the prior art;
(D) the level of one of ordinary skill;
(E) the level of predictability in the art;
(F) the amount of direction provided by the inventor;
(G) the existence of working examples; and
(H) the quantity of experimentation needed to make or use the invention based on the content of the disclosure.

Wands (noting that this is not an exhaustive list of potential factors).  Although relied upon daily in the patent system, the Supreme Court did not reference the Wands factors in its analysis. This omission created a question of whether Wands and its factors are still applicable.
The second issue is related to the first, and it has to do with a subtle shift in the language that the court used in forming the test.  In Amgen , the Supreme Court offered repeated reference to “reasonable experimentation” rather than the typical “undue experimentation” standard.  This difference introduced potential confusion on whether the Court announced a distinct, new test.
In post Amgen cases, the Federal Circuit has resolved these two subtle points of confusion, holding (1) that there is no difference between the traditional statement of “without undue experimentation” and the Supreme Court’s similar wording of a “reasonable” amount of experimentation; and (2) that the Wands Factors continue to serve as the key approach to determining whether the amount of experimentation needed to make & use the invention is too much.  The case that explains this best is probably Baxalta Incorporated v. Genentech, Inc ., 81 F.4th 1362 (Fed. Cir. 2023).
Its new guidelines , published January 10, 2024, the PTO reviews Amgen and post-Amgen case law and concludes that examiners will continue applying the long-standing “undue experimentation” standard and In re Wands factors when evaluating enablement. Guidelines for Assessing Enablement in Utility Applications and Patents in View of the Supreme Court Decision in Amgen Inc. et al. v. Sanofi et al. , 83 Fed. Reg. 1563 (Jan. 10, 2024).
From my initial review, these guidelines do not appear remarkable, but simply serves the purpose of keeping everyone on the same page.  It remains to be seen whether the examiner corps will further increase its focus on functional genus claims – especially those directed to a large number of embodiments and whether examiners outside the traditional ‘unpredictable arts’ will alter their enablement examination practice.
To be clear, these are examination guidelines – guidance for patent examiners that supplement the Manual of Patent Examination Practice (MPEP). They are not “rules” and do not have the force of law.