Sony Music Publishing and Warner Chappell Music have launched a major legal battle against artificial intelligence company Anthropic, accusing it of unlawfully using copyrighted music to train its Claude AI models.
The lawsuit, filed in the US District Court for the Northern District of California, alleges that Anthropic copied and used tens of thousands of copyrighted musical compositions without permission. The publishers claim the material included lyrics and sheet music from some of the world’s best-known artists, including The Beatles, Taylor Swift and Michael Jackson.
The case places the music industry at the centre of the rapidly escalating fight over whether AI companies can use copyrighted creative work to build powerful generative AI systems.
What Sony and Warner are alleging
At the heart of the lawsuit is the allegation that Anthropic obtained copyrighted material through a combination of torrenting, scraping and downloading, and subsequently incorporated that material into the datasets used to train Claude.
The publishers say the alleged conduct was not limited to a handful of songs. They accuse Anthropic of using tens of thousands of compositions and argue that Claude can reproduce copyrighted lyrics when prompted by users.
Among the works identified in the lawsuit are “Eye of the Tiger”, “September”, “Uptown Funk”, “Livin’ on a Prayer”, “Hallelujah”, “All I Want for Christmas Is You”, “Ain’t No Mountain High Enough” and Taylor Swift’s “Paper Rings”.
Sony and Warner also allege that the material was used to help Claude generate large quantities of supposedly new lyrics, which they argue could become substitutes for legitimate copyrighted music.
In their complaint, the publishers described the alleged conduct as “one of the largest and most blatant ongoing thefts of intellectual property in history”.
Anthropic rejects the claims
Anthropic has pushed back against the allegations and says it intends to fight the case.
“This is the third lawsuit from the same lawyers, recycling allegations from cases already before the courts,” an Anthropic spokesperson said, according to Reuters. The company maintains that its AI training practices constitute fair use of copyrighted material.
The company has previously argued in copyright litigation that using copyrighted material to train AI can qualify as fair use under US law, although courts have drawn an important distinction between the act of training an AI system and the way copyrighted material was obtained.
That distinction could become particularly important in this case.
Why this case is different
The lawsuit comes amid a much broader confrontation between AI companies and copyright owners.
AI systems require enormous quantities of data to learn patterns in language, music, images and other forms of creative expression. Copyright owners, however, argue that their work cannot simply be harvested and used commercially without permission or payment.
Authors, publishers, news organisations, record companies and music publishers have therefore launched lawsuits against AI companies in an attempt to establish where the legal boundaries lie.
Anthropic is already familiar with the issue. In 2025, the company agreed to pay $1.5 billion to settle a class-action copyright case brought by authors. That case involved allegations surrounding copyrighted books used in AI training.
Sony and Warner now argue that the previous settlement has failed to deter Anthropic from allegedly continuing to use copyrighted material.
The publishers said in their complaint that Anthropic appears to regard previous copyright settlements as simply “the cost of doing business”, arguing that the $1.5 billion settlement was not enough to discourage further alleged infringement.
The music industry’s wider legal offensive
Sony and Warner are not the first major music publishers to take Anthropic to court.
Universal Music Group, Concord Music Group and ABKCO previously sued Anthropic over allegations involving copyrighted song lyrics. Those cases helped establish the music industry’s growing concern that generative AI could reproduce protected lyrics and other creative material without licensing agreements.
The latest lawsuit is significant because it brings Sony and Warner into the same fight, meaning the publishing arms of all three major music companies are now pursuing legal action against Anthropic.
For the music industry, the issue is bigger than whether a chatbot can produce a few lines of lyrics.
The concern is that AI companies could use decades of human creativity to build commercially valuable systems, while the songwriters, composers and publishers whose work helped provide the underlying material receive little or no compensation.
Billions of dollars could be at stake
Sony and Warner are seeking statutory damages of up to $150,000 for each copyrighted work allegedly infringed, as well as an order preventing Anthropic from continuing to use the disputed material.
Given the number of compositions involved, the potential financial exposure could run into billions of dollars.
The publishers are also seeking restrictions on Anthropic’s use of their copyrighted works, potentially making the case about more than compensation. A ruling could influence how AI companies source training material and whether licences will increasingly be required before copyrighted creative works can be incorporated into AI training datasets.
A defining battle for AI and copyright
The case ultimately raises a fundamental question: when an AI system learns from human creativity, where does learning end and copyright infringement begin?
For artists and music publishers, the answer could determine whether AI becomes another licensed technology that pays creators for their work or a system that can commercially benefit from vast libraries of existing creativity without traditional licensing.
For Anthropic and the wider AI industry, the case could help define how future AI models are trained and what companies are legally allowed to do with copyrighted material.
The courts will now have to decide whether Anthropic’s alleged use of music falls within the protections of fair use – or whether, as Sony and Warner contend, the company crossed the line into copyright infringement.
