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IPT News Q1 2023
27 February 20236 minute read

Reshaping the boundaries of patent law: The top cases before the Supreme Court this term

In the past few years, the Supreme Court has taken up a number of important patent law cases, including Minerva Surgical, Inc. v. Hologic, Inc. (clarifying the scope of assignor estoppel), US v. Arthrex (deciding that final written decisions of the PTAB’s administrative patent judges must be subject to review by the Director of the USPTO) and Helsinn Healthcare v. Teva (determining the impact of the 2011 America Invents Act on the on-sale bar of 35 U.S.C. § 102.

This term is no different. This month, IPT News takes a quick look at a few significant patent cases the Court will be considering, each with the potential to reshape the boundaries of US patent law.


Next month, the Court is set to weigh in on the thorny issue of enablement in Amgen v. Sanofi.

In a rare departure from the Solicitor General’s recommendation, the Court granted certiorari on the following question:

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 – ie, to cumulatively identify and make all or nearly all embodiments of the invention without substantial “time and effort”?

In other words, the petition asks: “What, specifically, must a patent applicant show to meet the §112 requirement that it must provide a description of its invention that would enable a “skilled artisan” to make and use the invention?”

Anti-PCSK9 antibodies

The patents at issue, owned by petitioners Amgen, Inc., Amgen Manufacturing Limited, and Amgen USA, Inc. (collectively, Amgen), disclose an antibody designed to lower cholesterol in the human body.

High levels of LDL cholesterol can lead to cardiovascular disease, heart attacks, and strokes. The human body regulates LDL cholesterol levels by removing LDL cholesterol from the bloodstream via LDL receptors in the liver. However, naturally occurring protein PCSK9 can bind to these LDL receptors and destroy them.

Tackling this natural phenomenon, Amgen engineered a monoclonal antibody to bind a specific region of PCSK9, thus preventing the protein from destroying LDL receptors. Amgen obtained an initial patent on its antibody in October 2011. After receiving FDA approval in August 2015, Amgen began selling the antibody under the trade name Repatha®. Amgen received multiple subsequent patents on its antibody technology.

Respondents Sanofi, Aventisub LLC, Regeneron Pharmaceuticals, Inc., and Sanofi-Aventis U.S., LLC (collectively Sanofi) also obtained a patent on an anti-PCSK9 antibody in November 2011 and, after receiving FDA approval in July 2015, began selling that antibody under the trade name Praluent®.

The key difference between the Amgen and Sanofi antibodies lies in their unique amino acid sequences.

Procedural history

In October 2014, Amgen filed a lawsuit against Sanofi, alleging that Praluent® infringes two of its subsequently obtained patents, US Patent Nos. 8,829,165 (the ’165 patent) and 8,859,741 (the ’741 patent). In response to Amgen’s allegations, Sanofi argued that the ’165 and ’741 patents, unlike the first Amgen patent, include broad claims that cover an “entire genus of antibodies” binding specific amino acid residues on PCSK9, without properly enabling those claims in the specification.

Sanofi pointed to the shared specification of the ’165 and ’741 patents, which discloses 3,000 antibodies that bind PCSK9. Amgen narrowed this list to 85 antibodies that block the interaction between LDL receptors and PCSK9 by at least 90 percent. Sanofi argued, however, that because Amgen only disclosed the amino acid sequences of approximately two dozen antibodies, and only disclosed the three-dimensional structures of two of those antibodies, the claims are not enabled. Sanofi asserted that Amgen only (and improperly) obtained the ’165 and ’741 patents in an attempt to broadly claim the entire genus of PCSK9-blocking antibodies after facing competition in the marketplace.

On appeal from the US District Court for the District of Delaware, the US Court of Appeals for the Federal Circuit agreed with Sanofi that Amgen’s claims were not enabled and subsequently denied Amgen’s petition for a rehearing en banc:

“Although the specification provides some guidance, including data regarding certain embodiments, we agree with the district court that ‘[a]fter considering the disclosed roadmap in light of the unpredictability of the art, any reasonable factfinder would conclude that the patent does not provide significant guidance or direction to a person of ordinary skill in the art for the full scope of the claims.’”

The Federal Circuit reasoned that even though the level of effort needed to “exhaust a genus” is not “dispositive,” the level of effort needed to practice the full scope of the claims is still relevant to the enablement analysis.

Enablement requirement to be clarified

In its petition to the Supreme Court, Amgen asserts that, in its decision, the Federal Circuit improperly created a second test for enablement under § 112 by “raising the bar” for genus claims. While Amgen agrees that patents must enable skilled artisans to make and use individual embodiments across “the full scope” of the claims, it contends that the Federal Circuit never explained what language in § 112 suggests that “enablement turns on the cumulative time and effort required to make all variations of the invention one-by-one.”

The Supreme Court will therefore clarify what, specifically, a patent applicant must show to meet the enablement requirement under § 112. Arguments from Amgen and Sanofi will be heard on March 27, 2023.


In addition to Amgen v. Sanofi, there are numerous pending Supreme Court petitions that, if granted, will further shape the boundaries of patent law.

The scope of IPR estoppel under 35 U.S.C. § 315(e)(2) could be clarified if the Court grants certiorari in Apple, Inc. v. California Institute of Technology (22-203). The question presented is “whether the U.S. Court of Appeals for the Federal Circuit erroneously extended inter partes review estoppel under 35 U.S.C. § 315(e)(2) to all grounds that reasonably could have been raised in the petition filed before an inter partes review is instituted, even though the text of the statute applies estoppel only to grounds that ‘reasonably could have [been] raised during that inter partes review.’” In January 2023, the Supreme Court requested the Solicitor General to file a brief, which has not been submitted as of this writing.

Also pending is Teva v. GlaxoSmithKline, previously covered here – a case that has the potential to reshape Hatch-Waxman litigation and how generic pharmaceutical companies can be held liable for induced infringement.

The specific question presented is “whether a generic drug manufacturer's FDA-approved label that carves out all of the language the brand manufacturer has identified as covering its patented uses can be held liable on a theory that its label still intentionally encourages infringement of those carved-out uses.” In 2020, a divided Federal Circuit panel held that Teva could be liable for induced infringement even where it had sought to carve out the infringing use from its drug label.

The Federal Circuit denied a petition for rehearing en banc, leaving Teva on the hook for a $235 million damages award. Teva filed a petition for a writ of certiorari last summer, and a number of parties have filed amicus briefs. As with Apple, the Supreme Court has asked the Solicitor General to weigh in.