Dario Amodei’s Anthropic is facing yet another massive legal challenge.

Sony Music and Warner, both juggernauts in the music publishing industry, filed a major lawsuit against the AI company late Friday night, accusing it of “one of the largest and most blatant ongoing thefts of intellectual property in history.”

More specifically, the publishers said that Anthropic had, without permission, trained its AI models on “tens of thousands” of copyrighted compositions, asking for remuneration up to $150,000 per work, in addition to up to $25,000 for each time Anthropic intentionally stripped copyright data. As The Verge points out, that means damages could reach several billion dollars.

While the latest lawsuit is far from the first time a frontier AI lab has been accused of copyright infringement, this particular suit could be very difficult for Amodei and Anthropic to defend against. That’s because the suit names the exact same dataset of pirated works that Anthropic cofounder Benjamin Mann — who is listed as a defendant — was found to have illegally downloaded, culminating in the blockbuster $1.5 billion settlement in September 2025.

“Among the many millions of books that Defendants torrented from these illegal pirate websites were books containing the lyrics and sheet music to hundreds or more of Music Publishers’ copyrighted musical compositions,” the latest legal filing reads.

The works include massive hits like Bon Jovi’s “Livin’ on a Prayer,” Earth, Wind & Fire’s “September,” and Leonard Cohen’s “Hallelujah,” according to the suit.

“Defendants Anthropic and its founders Dario Amodei and Benjamin Mann have conducted a brazen campaign of illegally torrenting, scraping, and downloading copyrighted works on a massive scale in order to develop, operate, and reap enormous profits from Anthropic’s ‘Claude’ series of artificial intelligence models,” the suit reads.

Anthropic is now forced to argue that Sony and Warner are rehashing old news — which could put them in an extremely awkward spot, considering the company had to settle and pay out well over a billion dollars to rightsholders previously.

“This is the third lawsuit from the same lawyers, recycling allegations from cases already before the courts,” a company spokesperson told Reuters, saying that the company will defend itself “robustly.”

Anthropic will fall back on an already familiar defense — that training AI on copyrighted material amounts to fair use, a controversial legal framework that allows for limited access to copyrighted materials without permission — according to the spokesperson.

But given legal precedent — it’s been just over a year since Anthropic’s settlement — Amodei has his work cut out to wriggle out of compensating rightsholders whose intellectual property was vacuumed up without permission.

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