Sony Music Publishing and Warner Chappell, together with a group of publishers totalling 35 plaintiffs, filed a copyright complaint against Anthropic PBC and two of its founders in the Northern District of California on 28 August 2026. The docket carries it as 5:26-cv-09217; the complaint runs to 48 pages and pleads four counts.
What is pleaded
The counts cover acquisition of pirated song-lyric corpora from shadow libraries, a contributory infringement claim aimed personally at Dario Amodei and Benjamin Mann, scraping and training and output, and removal of copyright management information under Section 1202. The personal count is the structural move: it seeks to attach liability to the individuals who allegedly directed the acquisition decisions rather than only to the corporate entity.
What the common framing gets wrong
Two claims are circulating that the document does not support. The first is the "multi-billion dollar lawsuit" headline: there is no damages figure anywhere in the complaint. What exists is the statutory ceiling of up to $150,000 per work for wilful infringement — a per-work maximum a court may award, multiplied by a work count that has not been fixed. Exhibit B, the schedule of compositions, describes itself as a "non-exhaustive, exemplary list" and is not available on the public docket, so the multiplicand is not public either. Any dollar total in a headline today was computed by the outlet, not pleaded by the plaintiffs.
The second is that this is the first time Anthropic's founders have been named. It is not. Both are already defendants in earlier publisher litigation against the company, and this complaint itself cites a filing made by Mann in that case. What is new is the plaintiff group and the shadow-library theory, not the presence of the founders.
Where it sits
The Northern District of California is where the major AI copyright docket has concentrated, and a complaint is an allegation — nothing here has been tested. The section on copyright management information is the one specialists will watch: Section 1202 claims survive or die on whether identifying information was knowingly removed, which is a factual question about pipeline engineering rather than about music.