Sony Music and Warner Chappell sue Anthropic for copyright infringement in model training

Sony Music Publishing and Warner Chappell Music filed separate lawsuits in US District Court for the Northern District of California alleging that Anthropic illegally trained its models on "tens of thousands" of copyrighted works. The suits represent ongoing copyright challenges to AI model training practices.

Update (2026-09-02): Sony Music and Warner Chappell filed lawsuits against Anthropic alleging a 'brazen campaign' to train models on copyrighted music without permission, according to Ars Technica. The lawsuit cites evidence of Anthropic staff discussing piracy in internal communications, including references to zlibrary.