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U.S. Supreme Court Affirmed Patent Enablement Requirement in Amgen

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On May 18, 2023, the U.S. Supreme Court issued its opinion in Amgen et al. v. Sanofi.1  The Court unanimously affirmed the Federal Court’s holding that Amgen’s relevant patent claims were invalid as the patent failed “to enable any person skilled in the art . . . to make and use the [invention]” as required by 35 U.S.C. §112(a).  Specifically, the Court reasoned that Amgen’s patent failed to enable the full scope of the claimed antibodies, a scope determined to be “much broader than those 26 antibodies [identified in the specifications],” even allowing for a reasonable degree of experimentation.

Amgen’s patents at issue claim a class of monoclonal antibodies that can lower low-density lipoprotein (“LDL”) cholesterol levels.2 The claimed genus of antibodies bind to a particular region or “sweet spot” on a particular protein, PCSK9, involved in regulating the levels of LDL receptors.3  Because PCSK9 can degrade LDL receptors responsible for extracting LDL cholesterol from blood-stream, it can contribute to high cholesterol levels.  By binding to PCSK9 and blocking it from contributing to high cholesterol levels, members of Amgen’s claimed genus of antibodies were shown to be therapeutically effective at maintaining healthy cholesterol levels.  While the Amgen’s patents describe 26 exemplary antibodies, the claimed genus would encompass millions of antibodies—including those unknown at the time.  

After obtaining the ’165 Patent and the ’741 Patent, Amgen sued Sanofi for patent infringement.  The case was tried to a jury twice at the U.S. District Court for the District of Delaware.4 During the first jury trial, the jury found that Amgen’s relevant patent claims satisfied both the written description and enablement requirements under 35 U.S.C. §112(a).  On appeal, the Federal Circuit reversed the jury verdict and remanded for a new trial finding that the District Court erred by excluding post-priority date evidence of the written description and enablement.5 The second jury also sided with Amgen finding that the enablement requirement was met.6 Sanofi, however, moved for JMOL and, in alternative, for a new trial.  The District Court granted Sanofi’s motion for JMOL for lack of enablement and denied the motion for lack of written description.7 On appeal, the Federal Circuit affirmed the District Court’s finding a lack of enablement finding that the claimed genera—even with functional limitations—were broader than what is supported by the disclosed examples. In reaching its decision, the Federal Circuit found that “substantial time and effort” would be required “to reach the full scope of these claims [in Amgen’s patents].”8

In 2021, Amgen appealed to the Supreme Court. Despite a contrary recommendation from the Solicitor General, the Supreme Court granted certiorari to address the following enablement issue:

Whether enablement is governed by the statutory requirement that the specification teach those skilled in the art to “make and use” the claimed invention, 35 U.S.C. §112, or whether it must instead enable those skilled in the art “to reach the full scope of claimed embodiments” without undue experimentation—i.e., to cumulatively identify and make all or nearly all embodiments of the invention without substantial “time and effort.”

The Supreme Court ultimately affirmed the Federal Circuit’s holding.  The Court first outlined the statutory language of the Patent Act of 1790, which “made clear that [the invention’s] disclosure would ensure ‘the public may have the full benefit [of the invention or discovery], after expiration of the patent term.’”9  The Court also noted that the enablement requirement remain largely intact even as Congress has revised the patent laws over time.  Therefore, the Court argued that “the law secures for the public its benefit of the patent bargain by ensuring that, ‘upon the expiration of [the patent], the knowledge of the invention [i]nsures to the people, who are thus enabled without restriction to practice it.”10

The Court also revisited its prior decisions addressing the enablement requirement, including O’Reilly v. Morse, 15 How. 62 (1854), The Incandescent Lamp Patent, 159 U. S. 465 (1895), and Holland Furniture Co. v. Perkins Glue Co., 277 U. S. 245 (1928).  In Morse, the Court found a claim “too broad, and not warranted by law,” because “it covered all means of achieving telegraphic communication, yet Morse has not described how to make and use them all.”11  Similarly, in Incandescent Lamp, the Court sided with Edison finding that Sawyer and Man’s patent claimed much but enabled little, because Sawyer and Man “[i]nstead of confining themselves to carbonized paper, . . . they made a broad claim for every fibrous and textile material.”12 The Court turned to Holland Furniture, which similarly found a broad claim going beyond the specific starch glue it manufactured invalid for lack of enablement.13 From these cases, the Court concluded that

[i]f 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. In other words, the specification must enable the full scope of the invention as defined by its claims. The more one claims, the more one must enable.14  

The Court was clear to point out that their analysis “is not to say a specification always must describe with particularity how to make and use every single embodiment within a claimed class;” “[n]or is a specification necessarily inadequate just because it leaves the skilled artist to engage in some measure of adaptation or testing.”15 In support of these points, the Court pointed specifically to Wood and Minerals Separation,16 where claims were upheld because “a specification may call for a reasonable amount of experimentation to make and use a patented invention.”17

Regarding Amgen’s patents at issue, the Court did “not doubt that Amgen’s specification enables the 26 exemplary antibodies it identifies by their amino acid sequences.”18 Yet, the Court decided that “Amgen has failed to enable all that it has claimed, even allowing for a reasonable degree of experimentation.”19 The Court reasoned that (1) “Amgen seeks to monopolize an entire class of things defined by their function—every antibody that both binds to particular areas of the sweet spot of PCSK9 and blocks PCSK9 from binding to LDL receptors;”  (2) Amgen’s roadmap to make the claimed antibodies in the specification “merely described step-by-step  Amgen’s own trial-and-error method;” and (3) Amgen’s proposal for conservative substitution, which requires scientists to make substitution to the known amino sequences, was “an uncertain prospect given the state of art.”20

While Amgen raised three alternative arguments that (1) enablement requirement should not be analyzed by how long a person skilled in the art to make every embodiment within a broad claim; (2) the Federal Circuit raised the bar for enablement—reach the full scope of claimed embodiments without undue experimentation; and (3) finding otherwise can “destroy incentives for breakthrough inventions,21 the Court found these positions lacked merit.  While the Court agreed with Amgen that enablement is not measured against the cumulative time and effort it takes to make every embodiment within a claim, the Court found that “Amgen offers persons skilled in the art little more than advice to engage in ‘trial and error.’”22  Further, the Court disagreed with Amgen that the Federal Circuit had raised the bar for enablement.  Instead, the Court affirmed that the Federal Circuit’s decision was consistent with the enablement standard, specifically, “the more a party claims for itself the more it must enable.”23  Finally, the Court noted that the policy judgment for ensuring incentives for inventions belongs to Congress.24 Under this enablement standard, the Supreme Court ultimately found that Amgen’s 26 exemplary antibodies did not enable all antibodies across the full scope of the claims, and Amgen’s roadmap instructions were deemed insufficient as “little more than a trial-and-error process of discovery.”25

*Sophie Yan, a Baker Botts law clerk, assisted in the preparation of this article.

1 Amgen v. Sanofi, No. 21-757, 598 U.S. ____ (2023). 

2 The patent claims at issue in this case are claims 19 and 29 of U.S. Patent No. 8,829,165 (“’165 Patent”) and claim 7 of the U.S. Patent No. 8,859,741 (“’741 Patent”).

3 U.S. Patent No. 8,829,165.

4 See Amgen v. Sanofi, 227 F. Supp. 3d 333 (D. Del. 2017); see also Amgen v. Sanofi, No. 14-1317-RGA, 2019 WL 4058927 (D. Del. Aug. 28, 2019).

5 See Amgen v. Sanofi, 872 F.3d 1367 (Fed. Cir. 2017)

6 See Amgen, 2019 WL 4058927.

7 Id.

8 See Amgen v. Sanofi, 987 F.3d 1080,1093 (Fed. Cir. 2021).

9 See Amgen v. Sanofi, No. 21-757, 598 U.S. ____ (2023).  The Court referred to the Patent Act of 1790, which promised up to a 14-year monopoly to any applicant who “invented or discovered any useful art, manufacture, . . . or device, or any improvement therein not before known or used.” Act of Apr. 10, 1790, §1, 1, Stat. 110.

10 Amgen, 598 U.S. ____, at 8 (citing United States v. Dubilier Condenser Corp., 289 U. S. 178, 187 (1933); Grant v. Raymond, 6 Pet. 218, 247 (1832) (Marshall, C. J.); Whittemore v. Cutter, 29 F. Cas. 1120, 1122 (No. 17,600) (CC Mass. 1813) (Story, J.).

11 Id. at 10 (citing O’Reilly v. Morse, 15 How. 62, 113-117 (1854)

12 Id. at 11-12 (citing The Incandescent Lamp Patent, 159 U. S. 465, 472 (1895)).

13 Id. at 12 (citing Holland Furniture Co. v. Perkins Glue Co., 277 U. S. 245, 250-51 (1928)).

14 Id. at 13.

15 Id. at 13-14.

16 Wood v. Underhill, 5 How. 1 (1846); Minerals Separation, Ltd. v. Hyde, 242 U. S. 261 (1916).

17 Amgen, 598 U.S. ____, at 15 (emphasis added).

18 Id.

19 Id.

20 Id. at 15-16.

21 See id. 18-19.

22 Id. at 18.

23 Id.

24 Id. at 19.

25 Id. at 18.

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