Google holds illegal monopolies in ad tech, US judge finds, allowing US to seek breakup

Alphabet's (GOOGL.O), Google illegally dominated two markets for online advertising technology, a judge ruled on Thursday, dealing another blow to the tech giant and paving the way for U.S. antitrust prosecutors to seek a breakup of its advertising products.

U.S. District Judge Leonie Brinkema in Alexandria, Virginia, found Google liable for "willfully acquiring and maintaining monopoly power" in markets for publisher ad servers and the market for ad exchanges which sit between buyers and sellers. Publisher ad servers are platforms used by websites to store and manage their ad inventory.