Sony Music Publishing and Warner Chappell Music have accused Anthropic of building its AI business on mass intellectual property theft, alleging in a new lawsuit that the company harvested more than 20,000 copyrighted songs to train its Claude models. The publishers allege the trove spans everything from Christmas tunes to Taylor Swift hits, and they are seeking billions of dollars in statutory damages.

According to court documents, Anthropic allegedly conducted a "brazen campaign of illegally torrenting, scraping, and downloading copyrighted works on a massive scale in order to develop, operate, and reap enormous profits from Anthropic’s ‘Claude’ series of artificial intelligence (‘AI’) models." At the heart of the lawsuit is a stark allegation: that copyright infringement was not incidental to Anthropic’s rise, but central to its business model.

Filed late Friday in the U.S. District Court for the Northern District of California, the complaint names Anthropic co-founder and CEO Dario Amodei and co-founder Benjamin Mann as individual defendants. The publishers are seeking $150,000 per infringed work, plus $25,000 for each instance in which identifiable copyright management information was allegedly stripped.

Anthropic responded with a pithy statement: "We disagree with the publishers’ claims and we intend to defend ourselves robustly in court."

This is hardly Anthropic’s first brush with intellectual property law. Some of the lawyers behind this suit also represented authors in Bartz v. Anthropic, a class action alleging that the company illegally trained large language models (LLMs) on copyrighted books. In September, they secured a $1.5 billion settlement with Anthropic — the largest intellectual property settlement at the time—and are now pressing similar claims on behalf of Universal Music Group and Concord Music Group.

Additionally, there are ongoing suits of similar claims from BMG, ABKCO, and Round Hill Music.