Music publishers cast the case as a test of whether AI companies can build powerful systems on unlawfully obtained creative work; Anthropic’s position was not available before publication, leaving the allegations unanswered.

Sony Music Publishing, Warner Chappell and other publishers filed suit late Friday in federal court in Northern California, naming Anthropic and co-founders Dario Amodei and Benjamin Mann. Their complaint alleges a “brazen campaign of illegally torrenting, scraping, and downloading copyrighted works” to develop and profit from Claude.¹

The lawsuit broadens a copyright battle already confronting the AI lab. The publishers say Anthropic obtained thousands of songs, pointing to works including Eye of the Tiger, Ain’t No Mountain High Enough, All I Want for Christmas Is You and Taylor Swift’s Paper Rings. They allege Claude can return identical or near-identical copies of protected material and argue that training on it enables generated lyrics to compete with human songwriters.

Their account also reaches beyond music files. The complaint says Anthropic used pirate archives including Library Genesis and Pirate Library Mirror, acquiring millions of books—among them books containing lyrics and sheet music. That allegation follows a June 2025 ruling that distinguished between training on copyrighted books and acquiring them through piracy; Anthropic later agreed to pay more than $1.5 billion to settle authors’ claims tied to pirated works.²

The publishers want a jury trial and statutory damages of up to $150,000 per composition. “Even the most revolutionary of technologies must develop within the bounds of the law,” they say. Anthropic could not be reached for comment before the reports were published, so the lawsuit currently presents the publishers’ case without a public response from the company.¹