Music publishers Sony Music Publishing and Warner Chappell Music filed a copyright lawsuit against Anthropic on August 28, and unlike the string of similar suits before it, this one does not stop at the company. It names co-founder and chief executive Dario Amodei and co-founder Benjamin Mann personally as defendants, filed in the U.S. District Court for the Northern District of California.
Why the individuals matter
Most corporate copyright suits target the company alone, since a business entity is generally the one that profits and the one with money to pay a judgment. Naming Amodei and Mann as individuals is a more aggressive legal move, and the complaint explains why with a specific allegation: it says Mann personally downloaded about five million pirated books from Library Genesis in June 2021, before Anthropic had built out the piracy operation the complaint says followed. It adds that Anthropic employees went on to torrent roughly two million more titles from a second shadow library, Pirate Library Mirror, in July 2022.
That distinction shapes the complaint's four legal counts. One count of direct infringement through torrenting is brought against all defendants together. A separate count of contributory infringement through torrenting is aimed specifically at Amodei and Mann as individuals. Anthropic alone faces a further direct infringement count and a count under the Digital Millennium Copyright Act for removing or altering copyright management information, the embedded data that identifies a work's rights holder.
What the publishers say Anthropic actually did
Beyond the torrenting claims, the publishers allege Anthropic scraped song lyrics from licensed platforms including MusixMatch and LyricFind, and that its language model Claude was trained in part on datasets such as Common Crawl, The Pile, and Books3, which the complaint says contain copyrighted lyrics and sheet music obtained without a license.
The complaint also quotes an internal Anthropic planning document from 2024 that it says reads: "We don't want it to be known that we are working on this," cited in reference to a scanning operation the publishers allege was part of the same acquisition effort.
Eight specific songs are named in the filing: "Eye of the Tiger," "Ain't No Mountain High Enough," "All I Want for Christmas Is You," "Livin' on a Prayer," "September," "Hallelujah," "Uptown Funk," and Taylor Swift's "Paper Rings." The complaint states the publishers are asserting claims over tens of thousands of compositions in total, not just the eight listed as examples.
The suit seeks statutory damages of up to $150,000 for each work found to have been willfully infringed, plus up to $25,000 for each instance of copyright management information removal. At tens of thousands of compositions, that arithmetic puts the publishers' potential exposure figure in the multiple billions of dollars, which the filing itself frames as "one of the largest and most blatant ongoing thefts of intellectual property in history." The complaint also argues Anthropic's public positioning does not match its conduct, stating: "Despite branding itself as the 'ethical AI company,' Anthropic has repeatedly acted in ways that belie that image."
An Anthropic spokesperson responded: "We disagree with the publishers' claims and we intend to defend ourselves robustly in court."
Part of a pattern, not a one-off
This is the fifth major music-copyright suit filed against Anthropic. Universal Music Publishing Group, Concord, and ABKCO sued first in October 2023 over roughly 500 songs, a case later transferred to California. The same three publishers filed again in January 2026 over more than 20,000 works, seeking upward of $3 billion. BMG followed in March 2026 over 493 compositions, and Round Hill Music filed on August 17, 2026, seeking up to $1 billion per defendant. The Sony and Warner Chappell suit, filed eleven days later, is the largest and most pointed yet.
The torrenting allegations echo a case Anthropic has already lost once. In 2025, the company agreed to pay $1.5 billion to settle Bartz v. Anthropic, a lawsuit brought by book authors over the same Library Genesis and Pirate Library Mirror downloads described in this new complaint. That settlement evidently did not deter the music publishers, whose complaint argues it should have carried more weight: a $1.5 billion payout is a rounding error against Anthropic's valuation, which investors have pushed well past $100 billion.
What this means going forward
Anthropic's book-piracy legal exposure is now established precedent rather than a hypothetical, thanks to the Bartz settlement, and this suit is a bet by the music industry that the same conduct applies to lyrics and sheet music. Naming Amodei and Mann personally raises the stakes further: if a court accepts that individual founders can be held liable for a company's training-data decisions, it changes the calculation every AI lab makes about who signs off on how data gets collected. For now, the case is in its opening stage, and Anthropic has signaled it will contest the claims rather than settle early.
