Sony Music Entertainment and Universal Music Group have a new grievance with AI start-up Suno.

The two music companies on Friday filed a new, 45-page lawsuit in the U.S. District Court in the District of Massachusetts against the AI music-generation company, alleging Suno’s new model, backed by several other music companies, still infringe Sony Music and UMG’s copyrighted works. The two (along with some of their respective imprints, named as fellow plaintiffs) alleged Suno’s admission that its new “v6” family of models trained upon the outputs of its previous models meant that, despite the company’s claims that its new models do not infringe on copyrighted works, “training a ‘new’ model on the outputs of an infringing model does not eliminate the infringement; it launders it.”

“V6 is not a fresh start; it is the fruit of the same poisoned tree,” the labels claimed.

The lawsuit comes more than two years after the labels, together with Warner Music Group, sued Suno over allegedly training its AI models on the companies’ tracks without permission.

A Suno spokesperson called the labels’ claims “fundamentally flawed on both the facts and the law” and said its platform pulls “musical qualities” when a user inputs an artist’s name “not so that a user can imitate someone else’s work, but so that people learn the language of music and make something of their own.”

“We have doubled down on this goal, launching v6 in partnership with WMG, BMG, and Believe,” the spokesperson said. “v6 was trained on content licensed from our partners, interactions including creations and preference signals from our community, and the accumulated learnings from our team. We are excited for a future where AI and the music industry continue to strengthen one another and build entirely new product experiences for artists, fans, and the broader music community.”

Suno has admitted it scraped data from publicly available resources, including YouTube, Deezer and more, though company executives have claimed its training metadata does not include artists’ names, cannot replicate material it was trained on and that Suno was increasingly trying to improve impersonation detection. Still, the labels claimed in the new suit, the deals reflect an admission by Suno that a market exists for licensing labels’ work, even as the company claims in court its training of its initial models adhered to the “fair use” doctrine.

The complaint also puts a number to the recordings Sony Music and UMG allege Suno infringed on since its debut: 60,202, a total the labels claimed “remain only a small portion” of the overall works violated.

Since the initial suit in June 2024, WMG, BMG and Believe each have signed deals with Suno to license their content, which helped power the “v6” models unveiled last week.

In the label-backed licensing announcement, Suno claimed all past models of its product that trained on unlicensed data — those that spurred such lawsuits — would no longer be supported. But Sony Music and UMG claimed that, because the new family of models is partially built on users’ outputs derived from those former models, they remain in violation of the labels’ copyrighted works.

“It is a product of those tainted models and of the unauthorized copies of Plaintiffs’ recordings that Suno retains and continues to use,” the labels claimed. “Thus, every model Suno has ever released—from its earliest versions through v6—is the product of, and continues to exploit, Suno’s unauthorized copying of the Copyrighted Recordings.”

The new lawsuits reflect the legally mercurial nature of AI music generation and the training of AI models. Round Hill Music, an independent music publisher, sued the company for $1 billion last month, while Americana singer Jason Isbell led a lawsuit against the company last month that seeks class-action status, alleging it allowed users to produce outputs based on artists’ identities without musicians’ consent.

UMG in particular has flexed a litigious arm against companies such as Anthropic and the music distributor DistroKid, which it alleged on Wednesday was flooding the market with AI-generated tracks that contributed to an “AI-slop pipeline.” Its licensing deals have been limited to companies that have kept their outputs confined to their respective platforms, including Suno competitor Udio and AI-powered remixing products on Spotify and the app Hook.

The labels have asked the court to declare that Suno infringed upon their works, award them statutory damages and force Suno to pay their attorneys’ fees.

“The harm Suno is causing goes far beyond these immediate economic consequences,” the complaint said. “Suno’s wholesale theft of the Copyrighted Recordings threatens the entire music ecosystem and the numerous people it employs. It also degrades the rights of artists to control their works, determine whether future uses of their works align with their aesthetic and personal values, and decide the products or services with which they wish to be associated. And it propagates the destructive theory that copyrighted music is free for the taking whenever a new technology claims that seeking and obtaining permission is just too cumbersome.”