The U.S. Justice Department is doubling down on its attempt to break up Google by asking it to give up the underlying technology powering the company’s digital ad network.

The Department of Justice (DOJ) is proposing Google sell two of its advertising products following a judge’s ruling that the tech giant illegally acquired and maintained a monopoly in the ad tech sector.

The DOJ contends that Google engaged in monopolistic practices by locking out competition through acquisitions, customer lock-ins, and controlling how transactions were made in the online advertising market.