The other two major labels made peace with Udio months ago. Sony did the opposite. On Monday it filed a fresh lawsuit in New York, Billboard reported, covering 30,117 recordings and leaving Udio facing a far bigger bill.

Turning peace into a weapon

The heart of the case is fair use, the defence Udio leans on to justify training on unlicensed songs. Courts weigh whether that use harms a market for the original work, and Sony has found a sharp answer.

Udio has since signed training licences with Universal, Warner, Kobalt, Merlin, Believe, and a US publishers’ group. That, Sony argues, proves a licensing market plainly exists. “A company that pays to license the very inputs at issue cannot credibly maintain that no market exists for those inputs,” the complaint reads.

In other words, the truce that looked like AI’s peace with the music business has become the labels’ weapon against the one holdout.