Udio is seeking to keep the size of its AI training dataset out of the public record in the copyright case brought against it by Sony Music Entertainment.
The company filed the motion on Monday (June 1) in the US District Court for the Southern District of New York, where US District Judge Alvin K. Hellerstein is overseeing the case.
Udio argues that competitors could use the figure to build rival products faster and more cheaply, according to the motion, which you can read here.
The move comes days after rival AI music platform Suno made the same request in the copyright case against it, before a federal court in Massachusetts.
Udio, which is owned by Uncharted Labs, wants to redact a single category of information from the plaintiffs’ recent court filings, which its lawyers call the “Training Data Number.”
The memorandum describes it as the total volume of audio files that the plaintiffs claim Udio used to train its generative AI models.
In a footnote, Udio said it does not concede that the figure alleged by the plaintiffs accurately reflects the volume of audio files it used.
Udio said it is not trying to seal the identity of any specific recording that the plaintiffs allege was in its training data.
“Udio does not seek to seal any particular recording Plaintiffs allege was included in the training data,” its lawyers wrote.
“Udio does not seek to seal any particular recording Plaintiffs allege was included in the training data… Rather, the sole information Udio seeks to impound is the total number of audio files allegedly used to train its model.”
Udio’s Motion
Nor, the filing said, is the company seeking to seal the additional works that the plaintiffs identified by inspecting Udio‘s training data.
“Rather, the sole information Udio seeks to impound is the total number of audio files allegedly used to train its model,” the filing stated.
Udio argued that the volume of its training data is a core component of the tool it built, in a field where many rival companies are seeking to develop competing products.
The memorandum said that if competitors learned the volume of Udio‘s training data, they could use it to “develop and refine competing products more rapidly and at a lower cost.”
It added that rivals could “extrapolate commercially sensitive insights about Udio‘s training methodology and strategy, thereby obtaining an unfair competitive advantage.”
The filing, which you can read here, said the plaintiffs gained access to the figure only through discovery, under a protocol that designated Udio‘s training data as “HIGHLY CONFIDENTIAL – ATTORNEYS’ EYES ONLY.”
That protocol required the plaintiffs to inspect the data in a secure room, on designated computers without internet access, the Udio filing said.
The memorandum was accompanied by a Declaration from Andrew Sanchez, Udio‘s Co-Founder and CEO.
In the declaration, Sanchez said the size of a training dataset “is closely guarded because it reveals strategic business choices regarding model architecture and product development.”
Sony Music Entertainment, along with Arista Music and Arista Records, is the only major-label plaintiff left in the case against Udio.
Universal Music Group settled its claims against Udio in October 2025, and Warner Music Group settled in November 2025.
All three major record companies originally sued Udio and Suno in June 2024, accusing both of “mass infringement” of copyright.
The sealing motion arrived days after Sony Music asked the same court for permission to add more than 30,000 recordings to its complaint.
Sony‘s proposed amended complaint asserts 30,442 copyrighted works that it says Udio “copied and ingested” into its AI models.
The label said it identified those works after gaining access to Udio‘s training data in discovery.
In Monday’s filing, Udio said it intends to oppose the plaintiffs’ motion to amend.
Udio and Suno both acknowledged in 2024 that they had used copyrighted recordings to train their models, but argue the practice is protected by “fair use.”
Udio is separately working with UMG and Warner on a licensed AI music platform set to launch in 2026.Music Business Worldwide
