Last week, a federal judge denied Sony Music’s motion to expand its lawsuit against AI company Udio to include another 30,000 allegedly infringed works. Now, Udio rival Suno has seized on that opportunity, asking the court to deny a similar motion in the lawsuit Sony filed against Suno, which would add some 60,000 copyrighted works to the case.

Previously, Sony Music hoped to increase its infringement action against Udio significantly after a “marathon discovery process” allowed it to identify some 30,000 works allegedly infringed upon within Udio’s training data. But Judge Alvin K. Hellerstein rejected Sony’s motion to amend its case two years into litigation and a mere few weeks ahead of an anticipated wrap of discovery.

“Adding more than 30,000 works near the close of document discovery would require substantial additional production and review, generate further disputes, and materially alter the scope of the case before me,” the judge wrote. “I recognize that Plaintiffs have the right to seek to stop infringement of, and recover damages for, all copyrighted works, but there is no requirement that it be done in this lawsuit.”

That means Sony Music’s legal battle against Udio will proceed with around 300 works at issue, rather than the full scope of alleged infringement.

“The court specifically observed that the addition of 30,000 works ‘would require substantial additional production and review’ of documents and ‘materially alter the scope of the case,’ creating a litigation that no ‘single judge could deal with,’” wrote attorney Britt Lovejoy, counsel for Suno.

“Suno respectfully requests that this Court consider the Udio court’s denial of the plaintiffs’ motion to amend in deciding the present plaintiffs’ nearly identical motion,” the filing reads. “For the same reasons that the Udio court denied the motion in that case, as well as the additional bases identified in Suno’s briefing, this Court should deny Plaintiffs’ motion here as well.”

The original complaint, filed two years ago in June, listed only 560 works. The company noted that adding “tens of thousands” of works would indeed require new discovery and even further delay a ruling.

“After two years of extensive fact discovery, Suno is entitled to a timely consideration of its fair use defense.”