Sony and Warner Sue Anthropic Over Song Lyrics

Sony Music Publishing and Warner Chappell filed a federal copyright lawsuit against Anthropic on August 28, accusing the AI company of building Claude using tens of thousands of copyrighted song lyrics pulled from pirate archives. The 48-page complaint, filed in the U.S. District Court for the Northern District of California, names CEO Dario Amodei and co-founder Benjamin Mann as individual defendants.

The suit arrives as Anthropic reportedly prepares for an IPO that could value the company at up to $2 trillion — a figure the publishers cite directly in the complaint. It is the fifth separate music copyright lawsuit against Anthropic in under three years, and the first to bring the publishing arms of both Sony and Warner into court simultaneously.

What Was Announced

Thirty-five publishing entities, including Sony Music Publishing, Warner Chappell Music, and companies affiliated with EMI and Hipgnosis, are listed as plaintiffs. The publishers allege Anthropic obtained copyrighted lyrics through pirate repositories, including Library Genesis and the Pirate Library Mirror, and also scraped licensed lyric platforms including Musixmatch and LyricFind.

The complaint alleges Anthropic used these materials to train Claude and that the model can reproduce copyrighted lyrics verbatim or near-verbatim. Named songs include “Ain’t No Mountain High Enough,” “All I Want for Christmas Is You,” “Eye of the Tiger,” “Hallelujah,” and “I Am the Walrus,” among thousands of others.

Anthropic responded with a brief statement: “We disagree with the publishers’ claims and we intend to defend ourselves robustly in court.”

How It Works

The damages math matters here. Publishers are seeking up to $150,000 per willfully infringed composition and up to $25,000 for each alleged removal of copyright management information — the metadata that identifies rights holders. The complaint identifies “tens of thousands” of compositions, which places theoretical statutory exposure in the multi-billion-dollar range. The publishers are also seeking a permanent injunction, a court-supervised accounting of Anthropic’s training data and methods, and destruction of infringing copies.

The complaint draws on evidence surfaced during the Bartz v. Anthropic authors’ case — which ended in a $1.5 billion settlement — to support its piracy allegations. A Munich court ruling from November 2025, which found that a language model “memorizing” lyrics constitutes reproduction and falls outside the text-and-data mining exception, is also cited.

What This Means for Users

For Claude users and API developers, there are no immediate product changes announced. Anthropic has existing guardrails in place — agreed to in 2025 — to prevent Claude from reproducing copyrighted lyrics in outputs. Whether those guardrails actually work is partly what this case will test.

The broader effect is on the AI industry’s legal exposure for training data. With publishing arms of all three major music groups — Universal (with Concord and ABKCO), Sony, and Warner — now in litigation against a single AI company, the lawsuits collectively represent a coordinated challenge to the fair use arguments Anthropic and others rely on. If courts rule against those arguments, AI labs could face mandatory licensing deals that raise training costs across the board.

What’s Next

The case is before the U.S. District Court for the Northern District of California, the same court handling Anthropic’s other music copyright suits. No trial date has been set. Anthropic has not provided a public timeline for its response to the complaint. The company’s reported IPO timeline — cited in press coverage as a late September or October 2026 target — could add urgency to any settlement negotiations, though neither side has confirmed talks.