A Manhattan jury has found that Live Nation and its subsidiary Ticketmaster operated as an illegal monopoly over large concert venues.

The verdict, reached Wednesday, could cost Live Nation and Ticketmaster hundreds of millions of dollars. In addition to financial penalties, the verdict could open the door for potential sanctions, including court-ordered measures that could force Live Nation to divest venues that it owns.

“It’s a great day for antitrust law,” said attorney Jeffrey Kessler, according to the Associated Press.

This is a breaking news story. Refresh for updates.