Justice Department lawyers on Tuesday revealed embarrassing details about Google’s conduct in the online ad industry as part of a new antitrust lawsuit. Despite evidence and allegations that Google rigged advertising auctions and effectively stole money from website publishers that rely on the company’s advertising tools, the DOJ will have a hard time winning the case and breaking up the company, some antitrust lawyers said.

Google has dominated a largely unregulated ad business that determines billions of digital ad placements every day across news and other websites—unrelated to the ads it sells on its search engine. DOJ lawyers led by longtime Google foe Jonathan Kanter said the company abused its position as an intermediary between advertisers and publishers—an ad-exchange business that is on pace to generate more than $30 billion in revenue per year. But it isn’t clear whether some of Google’s alleged conduct—which the company denies—is illegal, the lawyers said.