The Department of Justice will announce antitrust proceedings against Live Nation on Thursday

The Justice Department plans to announce an antitrust enforcement action against Live Nation, Ticketmaster’s parent company, as early as Thursday, according to three people familiar with the matter who spoke on the condition of anonymity to describe the matter before it becomes public.

The exact nature of the government’s announcement was not immediately clear, and sources warned the deadline could still be pushed back. But a federal lawsuit against Live Nation could radically change the entertainment industry, potentially limiting the company’s extensive reach as a concert promoter, venue owner and ticket seller.