Sony Music and Warner Chappell sue Anthropic, alleging Claude was trained on pirated song lyrics

Sony Music Publishing and Warner Chappell, the music publishing arms of Sony Music and Warner Music, have sued Anthropic in California federal court, alleging the AI company used pirated song lyrics and sheet music to train its Claude models.

According to the complaint, Anthropic pirated hundreds of lyrics and sheet music works from artists including The Beatles, Taylor Swift and Michael Jackson, obtaining material through piracy sources such as Library Genesis and the Pirate Library Mirror, while also scraping licensed lyric sites including Musixmatch and LyricFind.

"In blatant violation of copyright law, Defendants have unlawfully acquired troves of Music Publishers' musical compositions, and then systematically copied those works multiple times," the filing states, "including as the inputs to train Anthropic's Claude AI models and in the outputs those models generate."

The publishers are seeking statutory damages of up to $150,000 for each song the court finds was willfully infringed, plus up to $25,000 for each instance in which copyright management information was allegedly removed. With the complaint covering at least "thousands if not tens of thousands" of works, potential damages could reach billions of dollars.

Named songs include Marvin Gaye and Tammi Terrell's "Ain't No Mountain High Enough," Mariah Carey's "All I Want for Christmas Is You," Survivor's "Eye of the Tiger," Leonard Cohen's "Hallelujah," Mark Ronson and Bruno Mars' "Uptown Funk," The Beatles' "I Am the Walrus," and Taylor Swift's "Paper Rings" and "Cruel Summer."

Anthropic rejected the allegations, saying it will "defend ourselves robustly" in court. "This is the third lawsuit from the same lawyers, recycling allegations from cases already before the courts," a spokesperson told Fortune.

The suit is the latest escalation in a long-running legal battle: the same firm, Oppenheim and Zebrak, first sued Anthropic in October 2023 alongside Universal Music Publishing Group, Concord and ABKCO over roughly 500 songs, then filed a second suit in January covering more than 20,000 works and seeking more than $3 billion. Earlier this year, a US federal court approved a record $1.5 billion settlement in a copyright dispute brought by authors and publishers against Anthropic over its use of books.

The case lands as AI companies face intensifying scrutiny over training data practices, and its outcome could help define how music copyright applies to generative AI. Watch for how the court treats the piracy-source allegations and whether Anthropic moves to consolidate the overlapping cases.