How the Supreme Court’s Decision in Amgen v. Sanofi Impacts Pharmaceutical Patents

By: Nafsika Karavida

On May 18, 2023, the Supreme Court of the United States (the “Court” or “SCOTUS”) handed down its decision in Amgen Inc. v. Sanofi (“Amgen/Sanofi” or the “Amgen case”) [1] , a fairly notorious case among pharmaceutical companies and patent nerds.  Amgen/Sanofi is about the so-called enablement requirement in the Patent Act[2], which requires the inventor/patent applicant to disclose their invention to such a degree that a reasonably skilled person in the art to which the invention pertains can make and use the invention.  The “art” means the technology or science field of the invention.  For example, if the invention is a pharmaceutical product, a reasonably skilled biomedical scientist should be able to read the enablement/description of the invention and understand how to make and use it.

The Amgen/Sanofi holding concerns the disclosure requirement in the area of antibody engineering.  The controversy surrounding the case centers on whether the Court’s ruling affects the level of detail that an inventor must disclose about the invention or if it just confirms the Court’s prior decisions on the enablement requirement.  In this article, we break down the Amgen case and review whether the enablement requirement has indeed changed, now that almost seven months have passed since the Court handed down its ruling.

Background and Facts

Years ago, Amgen Inc. (“Amgen”) and Sanofi-Aventis US LLC (“Sanofi”) independently developed a so-called PCSK9-inhibiting drug.  In 2011, Amgen and Sanofi respectively obtained a patent each for the antibody employed in their drug.  Each of the patents describes the relevant antibody by its unique amino acid sequence.  The dispute in Amgen/Sanofi concerns two additional patents that Amgen obtained in 2014 and that relate back to the company’s 2011 patent.  These later-issued patents claim for Amgen “the entire genus” of antibodies which, by Amgen’s own admission, could potentially include millions of antibodies that (1) “bind to specific amino acid residues on PCSK9,” and (2) “block PCSK9 from binding to [LDL receptors]”[3].

For the readers without a background in biology, a genus can be described as a class or a type which hosts several different species (in layman’s terms “versions”) within it.  However, as part of its submission to the United States Patent and Trademark Office (“USPTO”), Amgen identified only the unique amino acid sequences of 26 antibodies that perform these two functions, which means that Amgen disclosed a drastically lower number of amino acid sequences than the potential number of antibodies and unique amino acid sequences covered by the patent.  Amgen also described two methods – the “roadmap” and the “conservative substitution”— that scientists could use to make other antibodies within the genus that perform the binding-and-blocking functions described in the patent.

After Amgen obtained the 2014 patents, it sued Sanofi for infringement.  Sanofi answered that it was not liable to Amgen for infringement because Amgen had not disclosed how to make all the antibodies within the genus it claimed and therefore not fulfilled the Patent Act’s “enablement” requirement.  The enablement provision requires a patent applicant to describe the invention “in such full, clear, concise, and exact terms as to enable any person skilled in the art … to make and use the [invention]”[4].  Sanofi alleged that Amgen’s disclosure – the “roadmap” and the “conservative substitution” – outlined for generating additional antibodies was “little more than a trial-and-error process of discovery”[5], and that Amgen’s patents failed to meet the enablement requirement because they claimed for Amgen potentially millions more antibodies than the company had enabled a person skilled in the art to make.

Amgen had effectively received two patents for all potential antibodies that bind to a specific receptor and block a certain reaction from happening.  This is possible, sometimes and under certain conditions, under the Patent Act and refers to a “functional” claim, which simplified means that such a patent covers all structures within that “genus” or “class” of structures that produce the function in question.  Consequently, a patent based on its function can be very wide in scope and monopolize a rather large scope of potential inventions.

The United States District Court for the District of Delaware granted Sanofi judgment as a matter of law, concluding that the claims at issue “are not enabled”[6].  The Federal Circuit affirmed[7] and the Supreme Court ultimately agreed as well.

Supreme Court’s Reasoning

Justice Gorsuch, who penned the unanimous decision for the Court, started by explaining the reasoning behind the enablement/disclosure requirement – namely, that it concerns a bargain.  The inventor bargains to receive a patent for their invention by disclosing, or enabling a person skilled in the art, how to make and use the invention, and in return is granted a monopoly to the invention for a limited amount of time.  In Justice Gorsuch’s own words, “The patent ‘bargain’ describes the exchange that takes place when an inventor receives a limited term of protection from competitive exploitation in exchange for bringing new designs and technologies into the public domain through disclosure for the benefit of all”[8].

The Court went on to cite its prior case law on enablement, and characterized the statutory command on enablement as “simple”:  “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[9].  Thus, the Amgen case boiled down to whether Amgen had revealed how to make the entire class of antibodies that its patent covered.  To complicate matters, though, and as confirmed by the Court, a specification must not always describe with particularity how to make and use every single embodiment within a claimed class – “It may suffice to give an example (or a few examples) if the specification also discloses some general quality … running through the class that gives it a peculiar fitness for the particular purpose”[10].  But, if undue experimenting is required to make the invention, the enablement criterion is not fulfilled.

The Court then took a closer look at the “roadmap” and the “conservative substitution” methods to determine if they actually enabled a person skilled in the art, without undue experimenting, to make all the antibodies claimed by Amgen.

The Roadmap and The Conservative Substitution

Citing Amgen’s brief, the “roadmap” directs scientists to: (1) generate a range of antibodies in the lab; (2) test those antibodies to determine whether any bind to PCSK9; (3) test those antibodies that bind to PCSK9 to determine whether any bind to the sweet spot as described in the claims; and (4) test those antibodies that bind to the sweet spot as described in the claims to determine whether any block PCSK9 from binding to LDL receptors.  The “conservative substitution” instructs a scientist to (1) start with an antibody known to perform the described functions; (2) replace select amino acids in the antibody with other amino acids known to have similar properties; and (3) test the resulting antibody to see if it also performs the described functions[11].

Prior SCOTUS Cases on Enablement

To further determine whether the disclosed method enabled the engineering of the class of antibodies covered by Amgen’s patent as required under the Patent Act, the Court compared Amgen’s disclosure with several of its prior enablement decisions.  Citing O’Reilly v. Morse[12], the Court noted that defendant Morse had claimed “all means of achieving telegraphic communication”[13], but had only described how to make and use some telegraphic communication.  In Consolidated Electric Light Co. v. McKeesport Light Co.[14], the inventors had claimed for their electric lamp with an “incandescing conductor” made of “carbonized paper…every fibrous and textile material”[15].  In Holland Furniture[16], a claim in the company’s patent covered all “starch glue which, [when] combined with about three parts or less … of water, will have substantially the same properties as animal glue”[17].

What these cases have in common and what the Court demonstrated by citing them is the very broad nature of the claims and the not-so broad disclosures.  In contrasting Amgen’s claims and disclosure to its prior case law on enablement and the statutory requirement, the Court stated that it did not amount to more than a “research assignment” and a “hunting license”[18].

As discussed further below, the Court also based its decision on the “bargain” requirement in patent law and its constitutionally based objective to encourage competition.  In the end, the glaring contrast of disclosing the structure of 26 antibodies but claiming potentially millions, as Amgen did, was too much for the Court.

Conclusion and Discussion

The Court’s reasoning should be considered in the context of the subject matter concerning which it decided, namely, that there is still much that is not known about antibodies and that the science remains “unpredictable”[19], as the Court stated.  The Amgen/Sanofi holding should also be considered in light of patent law’s key objective – to encourage competition in science and innovation and to make sure the invention will serve the public.  Indeed, the Court stressed the importance of the “bargain” in patent law and how the inventor receives a monopoly for a limited amount of time in exchange for revealing to the public how the invention is made and used – for the general benefit of all.  The Court plainly characterized this requirement as the quid pro quo premise of patent law.  By holding that Amgen’s claim was overly broad in relation to its disclosure, the Court effectively safeguarded the competitive space and research for potentially millions of antibodies yet to be discovered just within the specific class in question.  And yes, potentially millions of inventions with the corresponding dollar amount to match those millions of inventions as well.  Against this background, it is difficult to disagree with the Supreme Court.  The other side of that coin, though, is that granting and upholding broad patents could also incentivize science and competition by helping to protect a company’s scientific investment in a much larger area of research.

Criticism of the Court’s holding includes the yet very large amount of disclosure that Amgen did make in its submission to the USPTO, however not cited in the Court’s opinion, and if it was insufficient, then what indeed is enough disclosure; the Court did not provide much detail to clarify this point.  Patent law buff and founder of IP Watchdog, Gene Quinn, said the decision “because of the evidence, clearly ushers in a cataclysmic shift in the law of enablement” and that “the effect of the ruling” is that a specification always must describe with particularity how to make and use every single embodiment[20]. Bloomberg Law concluded that the decision allowed “more pharmaceutical companies to keep competing in the same areas of research and development”[21].

Robert Bahr, who was the Deputy Commissioner for Patent Examination Policy at the USPTO when the Supreme Court decided Amgen/Sanofi, and who is still with the USPTO, said on an IP Watchdog seminar this fall that the case did not change the law on enablement and that USPTO has instructed its examiners to “keep calm and carry on”[22].  He added that the USPTO is trying to align its examination of patents with applicable case law and the goal here is to ensure that more patents are being upheld when challenged in court[23].  He also said that one issue with Amgen’s disclosure was that it gave examples of antigens within only one small area of the genus and not across it – something that the USPTO is increasingly requiring in patent application specifications with regard to enablement.  Bahr also added that Amgen’s patents in question were examined years ago when broader claims were more likely to be accepted by the UPSTO, thus implying that the USPTO’s policy on this issue has changed since then.

It is safe to say that the Court put its foot down with regard to broad claims generally, and especially broad functional claims.  The lesson learned here is that broad-brushed claims that purport to monopolize whole classes by their function will be closely scrutinized – especially if the inventor does not even know how many species the class encompasses and has disclosed the structure of only a handful of the potential species within the genus.

[1] Amgen Inc. v Sanofi, 598 U.S. 594 (2023).

[2] U.S.C. Title 35

[3] Id. (citing Amgen v. Sanofi, 872 F.3d 1367 (Fed. Cir. 2017)).

[4] 35 U.S.C.A. § 112(a).

[5] Amgen Inc., 598 U.S. at 597.

[6] Amgen Inc. v. Sanofi, 2019 WL 4058927, at *13 (D. Del. Aug. 28, 2019).

[7] Amgen Inc. v. Sanofi, 987 F.3d 1080, 1088 (Fed. Cir. 2021).

[8] Amgen Inc., supra note 6 (Internal quotation marks omitted).

[9] Id., citing Holland Furniture Co. v. Perkins Glue Co., 277 U.S. 245 (1928).

[10] Amgen Inc., supra note 3 (internal quotation marks omitted).

[11] Id., at 613.

[12]O’Reilly v. Morse, 56 U.S. 62 (1853).

[13] Id.

[14] Consolidated Electric Light Co. v. McKeesport Light Co., 159 U.S. 465 (1895).

[15] Id.

[16] Holland Furniture Co. v. Perkins Glue Co., 277 U.S. 245 (1928).

[17] Id.

[18] Amgen Inc., supra note 3, at 614.

[19] Id. at 600.

[20] See SCOTUS Ushers in New Era of Enablement Law in Amgen Ruling,

[21] See In Amgen-Sanofi Decision, High Court Sticks to Patent Law Script,

[22] IP Watchdog seminar on October 12, 2023.

[23] Id.

This article is intended as a general discussion of these issues only and is not to be considered legal advice or relied upon. For more information, please contact RPJ Associate Nafsika Karavida who counsels clients on employment, intellectual property, corporate and transactional, and cross-border commercial law. Ms. Karavida is admitted to practice law in Connecticut, New York, Sweden, the European Union, and before the United States Patent and Trademark Office (limited recognition, passed Patent Bar Exam March 2023, admission pending).