Sony Music Publishing, Warner Chappell, and various other music publishers have filed a lawsuit against Anthropic and co-founders Dario Amodei and Benjamin Mann, claiming the AI lab initiated a “brazen campaign of illegally torrenting, scraping, and downloading copyrighted works.”

The complaint, which was submitted late Friday in the U.S. District Court for the Northern District of California, was initially reported by Music Business Worldwide. The publishers accuse Anthropic of “blatant theft” by utilizing thousands of copyrighted materials to develop its AI model Claude.

“We contest the publishers’ allegations and plan to defend ourselves vigorously in court,” an Anthropic spokesperson stated in an emailed comment to TechCrunch.

This is not the first intellectual property lawsuit Anthropic has encountered. Some of the same attorneys involved in this case also represent Concord Music Group and Universal Music Group in a lawsuit filed in January and led the Bartz v. Anthropic case, where a group of authors accused Anthropic of employing copyrighted materials to train products such as Claude. Anthropic was ordered to pay $1.5 billion in the significant Bartz case after a judge determined that while it was permissible for the AI lab to use copyrighted works, it was illegal to acquire that content through piracy.

Although the cases present similar claims, there are essential distinctions. This recent lawsuit is particularly extensive and expands upon prior cases, including allegations of “flagrant piracy” through illegal torrenting to obtain millions of copies of books, which includes those containing lyrics and sheet music.

Article was revised to incorporate Anthropic’s statement.