Sony and Universal Music Group have initiated a fresh legal action against Suno, the AI music startup. The complaint alleges that Suno’s newly released v6 vocal synthesis model continues to breach the labels’ copyrights. Both companies have previously refused to enter a licensing arrangement with Suno, and the lawsuit seeks to halt distribution of the contested technology.
According to the filing, the v6 system was trained on outputs generated by Suno’s earlier models, which themselves were built using music scraped from YouTube and other platforms without permission. Plaintiffs argue that this chain of training propagates the original infringement, allowing the new model to reproduce protected melodies despite the absence of direct exposure to the copyrighted recordings.
When the v6 version launched, Suno’s co-founder Jack Brody told The Verge the model was “trained from the ground up, with a new set of data,” and mentioned inclusion of “user data,” though he declined to elaborate. Later, Suno spokesperson Rachel Racusen confirmed to The Verge that the training set comprised “creations” from users, licensed partner content, community interaction signals, and internal learnings, without clarifying whether uploaded audio files were part of the dataset.
Sony’s complaint further accuses Suno of employing a technique known as distillation to build v6. Under this approach, the new model allegedly mimics the behavior of earlier “teacher” models, which were themselves trained on the unlicensed recordings cited by the plaintiffs. The allegation suggests that indirect copying through distillation still constitutes infringement.
The filing states that even a system not directly exposed to the plaintiffs’ recordings “is informed by, and benefits from, Suno’s retained unauthorized copies.” By highlighting this indirect reliance, the labels argue that Suno’s current methodology continues to profit from material that was never cleared for use.
Both Sony and Universal conclude that without a genuine clean-sheet development process, Suno’s AI models will perpetually rely on data derived from infringing sources. The lawsuit therefore seeks not only damages but also an injunction compelling Suno to abandon any further training that incorporates unlicensed music, aiming to protect the labels’ copyrighted works.