Sony and Warner Music Publishing Arms Sue Anthropic Over AI Model Training Data

Publishing units affiliated with Sony Music and Warner Music have filed a federal copyright infringement lawsuit against artificial intelligence startup Anthropic, accusing the company of illegally using proprietary musical works to train its AI models. The legal action, submitted in the U.S. District Court for the Northern District of California and first reported by Yahoo Finance, names Anthropic alongside Chief Executive Officer Dario Amodei and co-founder Benjamin Mann as defendants.

The 48-page legal filing alleges that Anthropic engaged in systematic downloading, torrenting, and web scraping of protected compositions without authorization. According to the suit, the founders and the company used the materials to construct and refine the Claude series of generative AI systems, seeking to build a profitable enterprise off protected creative works. The plaintiffs characterize the activity as one of the largest ongoing intellectual property thefts in history.

The lawsuit significantly expands the legal claims facing Anthropic compared to earlier litigation in the music sector. For instance, a separate ongoing lawsuit brought by publisher BMG focuses on 493 specific compositions. In contrast, the joint suit by the Sony and Warner publishing arms alleges the unauthorized ingestion of tens of thousands of musical compositions across Anthropic's training infrastructure.

Music industry copyright architecture is structurally fragmented, as rights to lyrics, musical arrangements, and sound recordings are frequently divided among distinct entities including songwriters, music labels, and publishing houses. This structure exposes artificial intelligence developers to legal claims from multiple parties over the same underlying track. Moreover, plaintiffs pursuing statutory copyright infringement are not required to demonstrate explicit monetary harm in court to secure financial remedies.

The music publishers are seeking hundreds of thousands of dollars in statutory damages for each infringed work identified in the complaint. Given the broad volume of works referenced in the suit, potential statutory damages could translate into substantial financial exposure for the San Francisco startup.

The lawsuit represents another major legal challenge regarding Anthropic's data acquisition strategy. In September 2025, the organization resolved a prior legal dispute by agreeing to pay $1.5 billion to settle claims brought by literary publishers and book authors, which marked the largest copyright settlement in U.S. legal history.

The confrontation highlights the music industry's history of aggressively invoking copyright law against emerging technology platforms that distribute or process media, similar to the industry's legal strategies during the early era of peer-to-peer file sharing platforms like Napster and LimeWire. Anthropic was not immediately available to provide comment on the legal filing.