Sony and Warner's Publishers Sue Anthropic in Multi-Billion-Dollar Copyright Case
Sony Music Publishing and Warner Chappell Music filed a copyright lawsuit against Anthropic, the maker of the Claude AI assistant, on Friday, August 28, 2026, in the US District Court for the Northern District of California. The complaint calls the alleged infringement "one of the largest and most blatant ongoing thefts of intellectual property in history" and names Anthropic co-founder and CEO Dario Amodei and co-founder Benjamin Mann as individual defendants. Music Business Worldwide
The case is docketed as Sony Music Publishing (US) LLC et al v. Anthropic PBC et al, case number 5:26-cv-09217. PacerMonitor
At the centre of the dispute is a basic question of music-industry economics: who controls the compositions — the underlying songs, distinct from any particular recording of them — and whether an AI company can train its models on those songs without a licence. Sony Music Publishing and Warner Chappell Music are two of the largest music publishers in the world; between them they administer millions of copyrights covering songwriters across pop, country, hip-hop, rock and beyond.
The complaint identifies "tens of thousands" of allegedly infringed compositions. The publishers are seeking statutory damages of up to $150,000 per work wilfully infringed, plus up to $25,000 for each alleged removal of copyright management information — the identifying data embedded in a work, such as author and title, that the plaintiffs say was stripped during training. With tens of thousands of compositions in play, Anthropic's theoretical statutory exposure runs into the multi-billion-dollar range. Music Business Worldwide
This is not the first legal action aimed at AI companies over music rights. On August 17, 2026, Round Hill Music filed separate copyright-infringement lawsuits against both Suno, an AI music-generation platform, and Anthropic in the same Northern District of California. Music Business Worldwide / Instagram Around the same time, Sony Music Entertainment and Warner Records Inc — the recorded-music arms of the same corporate groups — filed their own suits against Anthropic and Suno alleging infringement of recorded music tied to AI training. Reuters / Facebook
The distinction matters. A composition copyright covers the song itself — the melody, lyrics and structure. A sound-recording copyright covers a specific performance of that song. The new lawsuit from Sony Music Publishing and Warner Chappell targets the composition side, meaning it concerns the rights of songwriters and publishers, not the recorded-music claims already in motion from the labels.
What gives this case its scale is the combination: tens of thousands of works, two of the three major publishers, statutory damages designed to punish wilful conduct, and named individual defendants in the company's leadership. The publishers' choice to name Amodei and Mann personally signals an intent to press the argument that the decision to train on copyrighted material was made at the top.
Anthropic has not yet publicly responded to the specific claims in the filing. The company has previously positioned itself as focused on AI safety, which makes the language of the complaint — calling the alleged conduct a "blatant" and "ongoing theft" — a direct challenge to that public framing.
For songwriters, the stakes are straightforward. A composition copyright is how a songwriter earns money when their work is used — through mechanical royalties, sync licences, performance income and more. If AI companies can train on those compositions without licensing them, the argument goes, the value of the underlying right erodes. If they cannot, the licensing market for AI training data becomes another revenue stream, and potentially a large one.
The case will now proceed through pre-trial motions and discovery in the Northern District of California. No trial date has been set.
