Sony Music Publishing, Warner Chappell and numerous other music publishers have sued Anthropic and co-founders Dario Amodei and Benjamin Mann, alleging the AI lab conducted a “brazen campaign of illegally torrenting, scraping, and downloading copyrighted works.” The lawsuit, which was filed late Friday in the U.S. District Court for the Northern District of California, was first reported by Music Business Worldwide . The publishers accuse Anthropic of “blatant theft” by using thousands of copyrighted works to train its AI model Claude.

The lawsuit, which was filed late Friday in the U.S. District Court for the Northern District of California, was first reported by Music Business Worldwide . The publishers accuse Anthropic of “blatant theft” by using thousands of copyrighted works to train its AI model Claude.

Anthropic could not be reached for comment prior to publication. TechCrunch will update this article if the company responds.

This isn’t the first intellectual property lawsuit Anthropic has faced. Some of the same lawyers behind this lawsuit also represent Concord Music Group and Universal Music Group in a case filed in January and led the Bartz v. Anthropic case, in which a group of authors accused Anthropic of using copyrighted works to train products like Claude. Anthropic was ordered to pay $1.5 billion in the landmark Bartz case after a judge ruled that while it was legal for the AI lab to use copyrighted works, it was not legal to acquire that content through piracy.

While the cases make similar arguments, there are key differences. This latest lawsuit is particularly broad and builds off the other cases, including by accusing Anthropic of “flagrant piracy” through illegal torrenting to obtain millions of copies of books, including those that contain lyrics and sheet music.