Amgen v. Sanofi: Seven Months In, Has Anything About Patent Enablement Changed?

Last term, the U.S. Supreme Court did something strange: the Court unanimously affirmed a circuit decision, which had unanimously affirmed a trial court decision. Little about the law seemed ripe for dispute or change, nevertheless, in Amgen v. Sanofi the Supreme Court spoke. Seven months later, innovators and patent practitioners are still scratching their heads. What impact, if any, does Amgen have? Is there a sign lower courts are interpreting Amgen as signaling a change in American patent law or did it merely ratify what already existed?

The question of law—the outcome on which all levels of the federal judiciary seemed in this case to agree—related to the patent enablement requirement under 35 U.S.C. § 112(a). The enablement standard means the applicant must explain in their application the necessary principles of how to make and use the claimed invention. The Amgen Court held that Section 112 requires that the specification of a patent application enable a person skilled in the art to practice the full scope of the claimed invention, not only a few specific embodiments of the invention. “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,” Justice Gorsuch wrote for the unanimous Court. “The more one claims, the more one must enable.” Further, the Court emphasized that “enablement is not measured against the cumulative time and effort it takes to make every embodiment within a claim” but rather the amount of guidance the specification supplies to the public. 

Amgen appears to strike especially at the practice of claiming therapeutic biomolecules according to their function, as opposed to their structure. At least one recent news article published in the journal Nature Biotechnology describes the Amgen decision as rendering “functional claims dead in the water.”  On the other hand, Amgen’s platitude that “the more one claims, the more one must enable” has already been hornbook patent law for decades, and functional claiming of biomolecules has by now been less favored for years.

Certainly, Amgen’s reach is not sweeping. Can it be that the Supreme Court’s decision is effectively a nullity, maintaining the status quo ante? The Supreme Court decided to speak—whatever the Court intended, surely the decision must mean something of consequence? Adding another wrinkle to the confusion, Justice Gorsuch did not once discuss or even cite in Amgen the predominant precedent usually applied to evaluate this legal issue, In re Wands, leading one observer to wonder whether the Court had implicitly repudiated Wands, or at least undercut its significance. The Federal Circuit and one trial court since the Amgen decision have asserted that Amgen changed nothing, and had merely “reaffirmed” existing law. Perhaps the Court signaled its mood that the United States Patent and Trademark Office (USPTO) and lower courts ought to approach enablement even more strictly.

Seven months since Amgen, the USPTO and federal courts have now had an opportunity to consider what, if any, significance it has. As of January 8, 2024, the Patent Trial and Appeal Board (PTAB) has cited Amgen in eight majority opinions, and federal courts have cited Amgen in 10 opinions:

• At the Patent Trial and Appeal Board:
  • Ex parte Pen, 2023 Pat. App. LEXIS 1857, Proceeding # 2022001764 (Pat. Trial & App. Bd. June 7, 2023);
  • Pelican Biothermal v. Va-Q-Tec AG, 2023 Pat. App. LEXIS 1936, Proceeding # PGR2021-00085 (Pat. Trial & App. Bd. June 16, 2023);
  • Ex parte O’Donoghue, 2023 Pat. App. LEXIS 3025, Proceeding # 2022004500 (Pat. Trial & App. Bd. Sept. 11, 2023);
  • Gillette Co., LLC v. Sphere USA, LLC, 2023 Pat. App. LEXIS 3126, Proceeding # PGR2022-00030 (Pat. Trial & App. Bd. Sept. 19, 2023);
  • Ex parte Postrel, 2023 Pat. App. LEXIS 2188, Proceeding # 2023001623 (Pat. Trial & App. Bd. July 11, 2023);
  • Ex parte Anderson-Baron, 2023 Pat. App. LEXIS 3524, Proceeding # 2022004057 (Pat. Trial & App. Bd. Oct. 18, 2023);
  • Ex parte Adhami, 2023 Pat. App. LEXIS 3553, Proceeding # 2023002654 (Pat. Trial & App. Bd. Oct. 20, 2023); and
  • Ex parte Kallen, 2023 Pat. App. LEXIS 4140, Proceeding # 2022004839 (Pat. Trial & App. Bd. Dec. 8, 2023);
• At United States Federal District Courts:
  • ESCO Grp. LLC v. Deere & Co., 2023 U.S. Dist. LEXIS 110633 (D.Del. June 22, 2023);
  • Orexo AB v. Sun Pharm. Indus., 2023 U.S. Dist. LEXIS 120114 (D.N.J. June 30, 2023);
  • In re Entresto Sacubitril/Valsartan Patent Litig., 2023 U.S. Dist. LEXIS 117240 (D.Del. July 7, 2023);
  • MHL Custom, Inc. v. Waydoo USA, Inc., 2023 U.S. Dist. LEXIS 157220 (D.Del. Sept. 6, 2023);
  • Teva Pharms. Int’l GMBH v. Eli Lilly & Co., 2023 U.S. Dist. LEXIS 171953 (D.Mass. Sept. 26, 2023);
  • Allergan USA, Inc. v. MSN Labs. Priv. Ltd., 2023 U.S. Dist. LEXIS 172641 (D.Del. Sept. 27, 2023); and
  • Oyster Optics, LLC v. Ciena Corp., 2023 U.S. Dist. LEXIS 190950 (N.D.Cal. Oct. 24, 2023);
• At the United States Court of Appeals for the Federal Circuit:
  • In re Starrett, 2023 U.S. App. LEXIS 14231, 2023 U.S.P.Q.2d (BNA) 684 (Fed. Cir. June 8, 2023);
  • Medytox, Inc. v. Galderma SA, 71 F.4th 990 (Fed. Cir. June 27, 2023); and
  • Baxalta, Inc. v. Genentech, Inc., 81 F.4th 1362 (Fed. Cir. Sept. 20, 2023).

Additionally, the Patent Trial and Appeal Board discussed Amgen in one concurring opinion:

• Ex parte Maxell, Ltd., 2023 Pat. App. LEXIS 2628 at *37–40, Proceeding # 2023001712 (Pat. Trial & App. Bd. Aug. 15, 2023) (Jeffery, J., concurring).

What early observations can be drawn from these decisions? What follows below are a few comments on the early impact Amgen has had in enablement arguments.

Amgen Is Not Displacing Wands

In re Wands “has become the ‘go to’ precedent for guidance on enablement” —the sort of decision found in the “legal standard” section of nearly every relevant judicial opinion. Wands defines enablement according to whether a person skilled in the art would need to resort to “undue experimentation” in order to practice the claimed invention. Wands sets forth eight factors for evaluating whether any necessary experimentation would be “undue.”  The Manual of Patent Examining Procedure explicitly says “[t]he examiner’s analysis must consider all the evidence related to each of [the Wands] factors.” However, Amgen never mentions Wands. So far, of the 18 controlling decisions to discuss Amgen, 13 of them also discuss Wands. The PTAB is the only tribunal so far to issue any decisions discussing Amgen but not Wands. Furthermore, an additional 21 cases issued since Amgen was decided cite Wands but do not mention Amgen at all.

In Baxalta, Inc. v. Genentech, the Federal Circuit, in a short paragraph, directly addressed the status of Wands in view of Amgen, writing “[w]e do not interpret Amgen to have disturbed our prior enablement case law, including Wands and its factors.”  However, in Baxalta itself, the panel applied Amgen but not Wands in its discussion of the patent owner Baxalta’s claims to antibodies that treat hemophilia A, explaining that “[t]he facts of this case are more analogous to—and are, in fact, indistinguishable from—those in Amgen.”  This suggests the court looked to the Supreme Court opinion in Amgen rather than Wands simply because Amgen, like the case before it, related in particular to functional claiming of biomolecules, namely antibodies.

This is not to say every tribunal is applying Wands as though Amgen had never happened. At the time of this writing, a handful of post-Amgen enablement decisions at the PTAB discuss Amgen but do not mention Wands:  Ex parte Postrel, Ex parte O’Donoghue, Ex parte Anderson-Baron, Ex parte Adhami; and Ex parte Kallen. None of these decisions clearly explain why the panel applied Amgen but not Wands, but a common feature in these cases is broad functional claiming of biological features. For example, in Postrel, the PTAB affirmed an examiner’s rejection of an application claiming a composition comprising at least two viruses, one engineered to be responsive to pH and the other engineered to be responsive to temperature. While not saying anything to rebuke the applicability of Wands, the PTAB panel only compared the claimed invention to the claims at-issue in Amgen, concluding that the claims were not enabled because, by way of comparison, the specification is even weaker than that of Amgen. In O’Donoghue, the PTAB applied Amgen to affirm a rejection of a claimed chimeric T cell antigen receptor (TCR) for lack of adequate written description and lack of enablement. In Anderson-Baron, the PTAB applied Amgen to partially affirm and partially reverse a rejection of claims to a method of genetically modifying a population of fruit flies to produce a target compound. In Adhami, the PTAB denied a petition for rehearing concerning a previous finding of a lack of enablement for a general method of “treating systemic infectious and neoplastic diseases” using “small-sized molecules,” citing Amgen for the argument that the inventor “leave[s] a scientist . . . forced to engage in ‘painstaking experimentation.’” Finally, in Kallen, the PTAB denied an appeal from final rejection of a claimed “method of stimulating an antigen specific immune response” using “mRNA encoding a coronavirus spike protein,” wherein the PTAB rejected the applicant’s claim of priority to a PCT application filed in 2011 for lack of enablement, concluding the written description of the priority document “lists literally hundreds of potential antigens” and “is little more than an invitation to experiment to see if . . . its teachings can be applied[.]”

The other decisions to discuss both Amgen and Wands generally apply the Wands factors, while citing to Amgen merely for additional support when discussing broad genus claims. In other words, with perhaps the exception of broad functional claiming of biological features, Wands still runs the show.

The Amgen Holding is Not Necessarily Limited to Functional Claim Language and Has Invited Potentially Strict Readings of Claim Scope

Most discourse surrounding Amgen relates to “functional” claims, especially in biotechnology, in which an invention is claimed by what is does (typically, a biomolecular binding target) rather than by its structure. In Amgen, the Supreme Court chided the patent owner for “seek[ing] to monopolize an entire class of things defined by their function” while offering in their description “little more than . . . research assignments.”  The discussion on enablement in Amgen itself was limited only to circumstances of functional claim language. Amgen does not discuss structural claims, methods, or other types of claims. Accordingly, one interpretation of Amgen is that the Supreme Court had a special interest in reining in functional claiming (particularly of antibodies), and the decision’s reach should be cabined as such. This seems to be reflected in that, as explained above, the few cases applying Amgen but not Wands relate to broad functional claims of biological subject matter.

However, the reality taking shape since Amgen does not necessarily appear quite so limited. Rather, Amgen is introducing the possibility of stricter analysis in general of the eighth Wands factor: the breadth of the claim. In June, the U.S. Circuit Court of Appeals for the Federal Circuit applied Amgen to invalidate patented claims to a method, specifically an improved Botox®-like cosmetic treatment. In Medytox, Inc. v. Galderma, the Federal Circuit invalidated claims to “responder rate” (i.e., efficacy) of “50% or greater” after 16 weeks from treatment. However, the specification’s examples had demonstrated the invention could only produce 16-week responder rates no better than 62%. Although the circumstances and technologies at-issue Medytox and Amgen differ widely, Judge Reyna applied Amgen’s command that the applicant must “enable the full scope of the invention as defined by its claims” in reasoning that the specification had not enabled the full scope of “50% or greater” responder rate, i.e., the full range of 50% to 100%. Because the examples presented in the specification could only achieve no better than 62% responder rate, the court reasoned that the specification had not enabled higher responder rates up to 100%. The court wrote that the “patentee chooses broad claim language at the peril of losing any claim that cannot be enabled across its full scope”.

Other tribunals have likewise applied Amgen in circumstances other than biomolecular function, including, for example, in the context of a chemical polymer having an extremely broad R substituent group and arbitrarily large number of monomer units (In re Pen); and a computer readable medium containing data and methods apparently for carrying out telepathy (or so the applicant had claimed) (In re Starrett). In Gillette v. Sphere USA, the PTAB applied Amgen within its Wands analysis for a claimed razor having a pivotable blade head.

Conversely, a few federal district courts have handily rejected attempts to apply Amgen to structural claims. In Orexo AB v. Sun Pharmaceutical Industries, a district court rejected the accused infringer’s assertion of Amgen as “inapposite in this case” where the claims at-issue were structural and “do[] not seek to ‘monopolize an entire class of things defined by their function.’”  Likewise, in ESCO Group v. Deere & Co., another district court rejected accused infringer Deere’s invitations to apply Amgen to claimed structural features of excavation equipment. The court considered the excavation equipment to “present[] a very different factual scenario from Amgen in which there were potentially millions of embodiments that had not been enabled.”

Considering the above, litigants should not assume Amgen’s command that the applicant must “enable the full scope of the invention” is limited solely to functional claims or to biological subject matter. While some tribunals have regarded Amgen as inapposite to narrow structural claims, the Federal Circuit has already applied Amgen strictly in contexts other than functional claiming.

Early Signs and Uncertainties

The various enablement cases handed down since Amgen carry some lessons. The Federal Circuit has twice, in Starrett and Medytox, called on Amgen to invalidate claims that have nothing to do with antibody binding affinities. Medytox, especially, in applying Amgen to invalidate a “50% or greater” claimed therapeutic efficacy, signals that the Federal Circuit (or Judge Reyna, at least) is taking Amgen’s “full scope” command quite literally. Three PTAB decisions (and one PTAB concurrence) similarly do not relate to biomolecule binding function.

To sum up the state of play:

• Wands probably still governs the core of the enablement inquiry;
• of the original Wands factors, Amgen probably invites a more searching and stringent analysis of the eighth factor: the breadth of the claims; and
• Amgen’s ambit is not limited to functional claims or biological subject matter.

What yet remains are questions of degree. Patent owners and prosecutors should consider, where practicable, claiming a more extensive array of narrower claims to mitigate invalidation risk as litigators work out the extent of Amgen’s “full scope” command in the coming years. In the still uncertain post-Amgen landscape, practitioners should learn from the Medytox and Gillette cases that tribunals may apply Amgen in any technical art and may use Amgen to strictly construe enablement analysis.

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