Judge Presses Google, DOJ on Ad Tech Breakup

In Alexandria, Virginia, a federal judge on Friday pressed lawyers from the U.S. Department of Justice and Google on the feasibility and timing of breaking up the tech giant's advertising technology business, marking the close of arguments in a high-stakes antitrust remedies trial.

U.S. District Judge Leonie Brinkema, who earlier this year found that Google maintained illegal monopolies in key digital advertising markets, heard final presentations from both sides during the three-hour session. The Department of Justice, joined by a coalition of states, urged Brinkema to order the sale of Google's AdX ad exchange, a platform where publishers auction ad space to buyers in real-time transactions. This tool, along with Google's publisher ad server, forms a core part of the company's ad tech stack, which processes an estimated 55 million requests per second and generates substantial revenue for Alphabet, Google's parent company.

The government's case centers on Google's decade-long practices that allegedly stifled competition by controlling multiple layers of the online ad marketplace, from ad sales tools for website publishers to demand from advertisers. DOJ attorney Matthew Huppert...