Universal and Sony sue Suno again, claiming its new v6 AI model launders old copyright infringement

Universal Music Group and Sony Music Entertainment sued AI music generator Suno for a second time on September 18, arguing that the company's newly launched "v6" model family is built on the same copyright infringement the labels first sued over in 2024 — even though Suno says v6 was trained from scratch on licensed music.

The joint complaint, filed in the U.S. District Court for the District of Massachusetts as case 1:26-cv-14275, identifies 60,202 specific sound recordings the labels say Suno copied without a license to build the models powering its music generation service. Under U.S. copyright law's cap of $150,000 per work for willful infringement, that count carries a theoretical maximum of just over $9 billion in statutory damages — before an additional claim for circumventing YouTube's anti-downloading technology, which could add roughly $150 million more.

The "Poisoned Tree" Argument

Suno launched v6 on September 9, telling reporters the new model suite was built in partnership with Warner Music Group, BMG, and Believe — all three of which have since signed licensing deals with Suno rather than continuing to fight it in court. Suno's chief product officer, Jack Brody, said at launch that v6 "was trained entirely from scratch, from the ground up," on data that "doesn't include data from Universal or Sony."

The labels' complaint doesn't dispute that v6's training data excluded their catalogs directly. Instead, it argues that v6 was built using the outputs of Suno's earlier models — the same models the original 2024 lawsuit alleges were trained on UMG and Sony recordings without permission. "Training a 'new' model on the outputs of an infringing model does not eliminate the infringement; it launders it," the complaint states, framing v6 as "the fruit of the same poisoned tree" — borrowing a legal doctrine more commonly seen in criminal evidence law, where evidence derived from an illegal search is itself inadmissible even if the derivative evidence was gathered legally.

A Fracturing Industry Response

The lawsuit highlights a split that has opened up among major labels over the past two years. All four major-label plaintiffs — UMG, Sony, Warner, and independent-focused BMG and Believe — joined or supported the original 2024 suit against Suno. Since then, Warner settled and licensed its catalog to Suno in November 2025, BMG followed in August 2026, and Believe signed on September 8, one day before v6 launched. UMG and Sony are now the only major holdouts, and their complaint explicitly cites the other labels' licensing deals as evidence that "a functioning market exists" for licensing recordings into AI training — undercutting any argument that Suno had no viable alternative to using unlicensed material.

What the Labels Are Seeking

Beyond statutory damages, UMG and Sony are asking the court for an injunction barring Suno from any further use of their recordings and have demanded a jury trial. Suno has not yet filed a public response to the new complaint.

The case adds to a growing body of litigation testing whether AI companies can insulate a new model from infringement claims tied to an earlier one simply by changing what data went into the newest training run, when the newest model's own outputs or intermediate representations were shaped by data now alleged to be unlawfully obtained. How a federal court rules on that question will matter well beyond the music industry, as the same "laundering" argument could apply to any AI company that iterates on prior model generations rather than training every version from an entirely clean dataset.

As reported by Music Business Worldwide and Variety.