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No Modification to a Challenger's Burden of Persuasion Upon Showing of Allegedly Anticipatory Prior Art

Client Alert | 1 min read | 10.20.08

In Technology Licensing Corp. v. Videotek, Inc. (Nos. 07-1441, -1463; Oct. 10, 2008), the Federal Circuit affirms a trial court's judgment of invalidity, noninfringement, and no inequitable conduct.

The Federal Circuit clarifies its recent ruling in PowerOasis, Inc. v. T-Mobile USA, Inc., 522 F.3d 1299 (Fed. Cir. 2008), on which party bears the burden of proof to prove entitlement to an earlier filing date. Despite legal commentary to the contrary, PowerOasis simply held that, when an alleged infringer has introduced sufficient evidence to show that there is anticipatory prior art dated earlier than the application date of the asserted patent, the patentee has the burden of going forward with evidence to the contrary. The Federal Circuit reiterates, however, that "[i]t is a long-standing rule of patent law" that the burden of persuasion never shifts and thus remains with the alleged infringer to show by clear and convincing evidence that a patent is invalid.

Similarly refusing to disrupt consistent case law on the issue of inequitable conduct, the court rejects an argument that an anticipatory prior art reference is material as a matter of law. A reference that is cumulative to other prior art of record cannot be material for purposes of inequitable conduct.

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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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