Durie Tangri

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Firm Summary: Durie Tangri

Date: 2026-05-09

Note: Effective January 3, 2023, the premier intellectual property litigation boutique Durie Tangri LLP combined with the global law firm Morrison & Foerster. The summary below reflects the historical practice of Durie Tangri and the current roles of its key partners within Morrison & Foerster's expanded IP litigation group.

Durie Tangri LLP was a highly regarded intellectual property and litigation boutique firm headquartered in San Francisco with a second office in Los Angeles. Prior to its merger, the firm was consistently ranked by publications like Vault and Chambers and Partners as one of the top IP boutique firms in the nation. In January 2023, the firm's 36 lawyers, including 12 partners, joined Morrison & Foerster, a major international law firm (AmLaw 100), significantly bolstering that firm's West Coast trial and IP litigation capabilities.

The firm was renowned for handling high-stakes, complex technology litigation. Its core specialty was patent, copyright, and trademark litigation for major Silicon Valley and technology companies. Historically, the firm represented industry leaders such as Google, Genentech, Activision Blizzard, LinkedIn, and Twitter. Its work spanned software, internet technologies, video games, and life sciences. The provided case data, showing a single appearance on the defendant side for Niantic, is not representative of the breadth or volume of the firm's practice, which was active for both plaintiffs and defendants.

The firm secured numerous significant courtroom victories prior to the merger. Notable public results include a defense verdict for Activision Blizzard in a copyright case over its Call of Duty Black Ops 4 video game, a defense verdict for Redbubble in a copyright and trademark case brought by Atari, and a successful defense for Google in the landmark Authors Guild v. Google book-scanning copyright case. The firm's partners have also been active in proceedings before the Patent Trial and Appeal Board (PTAB), representing clients in inter partes review (IPR) petitions.

The key leaders of the practice have transitioned into senior roles at Morrison & Foerster. Co-founder Daralyn J. Durie is a nationally recognized trial lawyer, ranked by Chambers and Partners in Band 1 for patent litigation. Other prominent founding partners who joined Morrison & Foerster include Ragesh K. Tangri, Mark A. Lemley, and Joseph C. Gratz, all of whom are highly ranked for their IP litigation work.