Sony Music, Universal Music Group Sue Suno Over Label-Backed Model: ‘Fruit of the Same Poisoned Tree’

Sony Music Entertainment and Universal Music Group, joined by a coalition of subsidiary labels, have escalated their legal battle against AI music startup Suno by filing a fresh 45-page complaint with the U.S. District Court for the District of Massachusetts on Friday. The major music companies allege that Suno's newly launched "v6" suite of AI models continues to violate their protected sound recordings, directly challenging the startup's public claims to the contrary. At the heart of the dispute is Suno's own acknowledgment that its v6 models were partially trained using outputs from its earlier, allegedly infringing systems—a fact the labels argue creates an unbroken chain of liability. The complaint contends that "training a 'new' model on the outputs of an infringing model does not eliminate the infringement; it launders it," adding that "V6 is not a fresh start; it is the fruit of the same poisoned tree." Suno has not yet issued a response. The District of Massachusetts, which has presided over numerous high-profile intellectual property cases, could see this dispute establish a benchmark for how derivative AI training is evaluated under copyright law.

For the first time, the litigation quantifies the alleged infringement, identifying 60,202 individual recordings owned by Sony Music and UMG that Suno is accused of using without authorization. The labels stress that this figure represents "only a small portion" of the total works impacted. Suno has previously conceded that it scraped publicly available data from services like YouTube and Deezer, though its executives have maintained that their training metadata excludes artist names, that the system cannot reproduce training content, and that impersonation detection is being improved. In rebuttal, the labels argue that Suno's recent licensing agreements with Warner Music Group, BMG, and Believe actually undermine its fair use defense by demonstrating a viable market for authorized use of their catalogs. Warner Music Group, an original plaintiff in the 2023 lawsuit alongside Sony and UMG, later pivoted to a licensing deal that enabled the v6 models released last week. As one expert in music copyright law observes, "The existence of licensing markets is often a decisive factor in fair use analyses, and these agreements could significantly weaken Suno's position."

This legal development arrives more than two years after the three major labels first sued Suno for unauthorized training on their tracks. When introducing v6, Suno pledged to retire all earlier models trained on unlicensed data. However, Sony and UMG counter that because the new models are partly derived from user outputs generated by those older systems, they remain tainted. "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 assert. "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 complaint seeks a court declaration of infringement, statutory damages, and attorneys' fees. This case unfolds amid a broader landscape of unresolved AI music copyright issues, including a $1 billion lawsuit filed against Suno by independent publisher Round Hill Music last month and a proposed class action by Americana artist Jason Isbell, who claims the company allowed users to imitate artists' identities without consent.

The wider legal terrain for AI music generation remains unsettled. UMG has also pursued legal action against Anthropic and distributor DistroKid, the latter accused on Wednesday of flooding the market with AI-generated tracks that feed an "AI-slop pipeline." To date, UMG's licensing arrangements have been confined to platforms that keep AI outputs within their own ecosystems, such as Suno competitor Udio and AI remixing tools on Spotify and the Hook app. In their complaint, the labels frame the stakes as existential for the music industry. "Suno's wholesale theft of the Copyrighted Recordings threatens the entire music ecosystem and the numerous people it employs," the filing states. "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." The labels further warn that Suno's conduct "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."