Duke University v. Sandoz Inc.

Duke University · United States Court of Appeals for the Federal Circuit · November 18, 2025 · No. 24-1078

Summary

The United States Court of Appeals for the Federal Circuit reversed a district court judgment upholding the validity of claim 30 of U.S. Patent No. 9,579,270. The court held that no reasonable jury could have found, by clear and convincing evidence, that Sandoz failed to prove inadequate written description. The specification did not provide a representative number of claimed species or sufficient structural guidance, or “blaze marks,” directing a skilled artisan to the claimed subgenus of prostaglandin F analogs.

Court
United States Court of Appeals for the Federal Circuit
Writing for the Court
Stark, Circuit Judge; Dyk, Circuit Judge; Stoll, Circuit Judge
Jurisdiction
United States Court of Appeals for the Federal Circuit
Decision date
November 18, 2025
Docket number
24-1078
Procedural posture
Sandoz appealed from a judgment of the United States District Court for the District of Colorado holding that Sandoz failed to prove claim 30 of U.S. Patent No. 9,579,270 invalid for lack of adequate written description. The district court denied Sandoz's motions for judgment as a matter of law and for a new trial.
Standard of review
The Federal Circuit reviewed the denial of judgment as a matter of law under Tenth Circuit law and applied de novo review. Reversal was warranted only if, without weighing witness credibility, the evidence permitted only the moving party's conclusion. The adequacy of written description is a question of fact, and invalidity must be proved by clear and convincing evidence.
Precedential value
Published and precedential
Parties
Sandoz Inc. v. Duke University, Allergan Sales, LLC
Disposition
reversed

Topics

patent lawpatent infringementstandard of reviewappellate procedurecommercial litigation

Practice areas

patent lawpatent infringementappellate procedurecommercial litigation

Questions Presented

  1. Whether the district court should have granted judgment as a matter of law that claim 30 of the '270 patent is invalid for lack of adequate written description under 35 U.S.C. § 112(a).
  2. Whether the patent specification adequately described the claimed subgenus of prostaglandin F analogs, including compounds with an amide at the C1 position and phenyl at the Z position, by disclosing a representative number of species or sufficient common structural features and blaze marks.

Holdings

  1. Claim 30 is invalid for lack of adequate written description because the specification did not allow a person of ordinary skill in the art to visualize or recognize the claimed subgenus of prostaglandin F analogs.
  2. Judgment as a matter of law was required because no reasonable juror could have found, by clear and convincing evidence, that Sandoz failed to prove the written-description invalidity defense.

Key quotations

Written description of an invention claimed as a genus of chemical compounds, as here . . . requires description not only of the outer limits of the genus but also of either a representative number of members of the genus or structural features common to the members of the genus, in either case with enough precision that a relevant artisan can visualize or recognize the members of the genus. (8)
Following [such a] maze-like path, each step providing multiple alternative paths, is not a written description of what might have been described if each of the optional steps had been set forth as the only option. (13)
The specification fails to provide the relevant artisan with sufficient blaze marks or structural commonalities among the claimed compounds to lead her to conclude that the inventor actually possessed the claimed invention. (17)

Factual background

Duke University and Allergan Sales, LLC owned all rights in the '270 patent, which claims methods of growing hair using compositions containing specified prostaglandin F analogs. Allergan marketed Latisse, a bimatoprost product, and Sandoz sold a generic version; Sandoz stipulated that its product infringed claim 30. At trial, Sandoz's expert testified that the claim covered thousands of compounds but that the specification disclosed no specific claimed embodiment and insufficient common structural features, while Allergan's expert offered contrary testimony. The jury found no invalidity and awarded $39 million in damages.

Procedural history

Duke University and Allergan Sales, LLC sued Sandoz in 2018 for infringement of claim 30 of the '270 patent. Sandoz stipulated to infringement but challenged validity. After a five-day jury trial, the jury rejected Sandoz's written-description, enablement, and obviousness defenses and awarded Allergan $39 million. The district court denied Sandoz's post-trial motions, and Sandoz timely appealed. The Federal Circuit reversed on written-description grounds and did not reach Sandoz's other principal arguments.

Remand instructions

None stated. The district court's judgment was reversed.

Court Document

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