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To Satisfy the Written Description Requirement for a Genus, Sufficient Species Must Be Shown

Client Alert | 2 min read | 09.17.08

The Federal Circuit, in Carnegie Mellon University v. Hoffman-La Roche Inc. (No. 2007-1266, -1267; Sept. 8, 2008), affirms the District Court for the Northern District of California's finding of invalidity, holding that the asserted claims of U.S. Patent Nos. 4,767,708 (the '708 patent) and 5,126,270 (the '270 patent) and certain asserted claims of U.S. Patent No. 6,017,745 (the '745 patent) lack a proper written description.

Plaintiffs-Appellants Carnegie Mellon University and Three Rivers Biologicals, Inc. (Carnegie Mellon) brought suit against Roche for patent infringement, asserting that Roche's recombinant plasmid pLSG5 -- which can be used to express Thermus aquaticus (Taq) DNA polymerase -- infringes their patents. In response, Roche filed separate motions for summary judgment of, inter alia, invalidity for lack of written description, which the district court granted. The district court concluded that the patents lacked an adequate written description under Regents of University of California v. Eli Lilly & Co., 119 F.3d 1559 (Fed. Cir. 1997), since the claims encompass a cloned polA gene from any bacterial source, but the specification only describes plasmids containing the polA gene from Escherichia coli. On appeal, Carnegie Mellon argued that the district court had erred in granting Roche's motions for summary judgment of invalidity of the '708, '270, and '745 patents because their invention involves the combination of well known elements to create a general biotechnological tool.

With respect to the issue of invalidity of the patents, the Federal Circuit notes that the appealed claims of the patents "are directed to recombinant plasmids that contain a DNA coding sequence that is broadly defined, and only by its function, viz., encoding DNA polymerase I," and further, that "the generic claims are not limited to a single bacterial species, but broadly encompass coding sequences originating from any bacterial species." In addition, the Federal Circuit observes that at the time of invention, out of thousands of bacterial species, only three bacterial polA genes had been cloned, and only one of these genes had been described in the patents at issue. Moreover, despite the description in the patents that "an important feature of this invention [is] that the cloned polA gene fragment contains essentially none of or at the most only a portion of the activity of its natural promoter," the patents "fail to disclose the nucleotide sequence or other descriptive features for a polA gene (including the promoter sequence) from any bacterial source other than E. coli." As a result, the Federal Circuit concludes that no genuine issues of material fact existed as to whether the written descriptions of the patents at issue adequately support the appealed claims, and therefore, the Court affirms the district court's grant of summary judgment of invalidity.

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Client Alert | 5 min read | 12.12.25

Eleventh Circuit Hears Argument on False Claims Act Qui Tam Constitutionality

On the morning of December 12, 2025, the Eleventh Circuit heard argument in United States ex rel. Zafirov v. Florida Medical Associates, LLC, et al., No. 24-13581 (11th Cir. 2025). This case concerns the constitutionality of the False Claims Act (FCA) qui tam provisions and a groundbreaking September 2024 opinion in which the United States District Court for the Middle District of Florida held that the FCA’s qui tam provisions were unconstitutional under Article II. See United States ex rel. Zafirov v. Fla. Med. Assocs., LLC, 751 F. Supp. 3d 1293 (M.D. Fla. 2024). That decision, penned by District Judge Kathryn Kimball Mizelle, was the first success story for a legal theory that has been gaining steam ever since Justices Thomas, Barrett, and Kavanaugh indicated they would be willing to consider arguments about the constitutionality of the qui tam provisions in U.S. ex rel. Polansky v. Exec. Health Res., 599 U.S. 419 (2023). In her opinion, Judge Mizelle held (1) qui tam relators are officers of the U.S. who must be appointed under the Appointments Clause; and (2) historical practice treating qui tam and similar relators as less than “officers” for constitutional purposes was not enough to save the qui tam provisions from the fundamental Article II infirmity the court identified. That ruling was appealed and, after full briefing, including by the government and a bevy of amici, the litigants stepped up to the plate this morning for oral argument....

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