US DOJ finds Google guilty of advertising monopoly

Google, undisputed king of search, problematic ruler of browsers, and somewhat even-keeled competitor for mobile operating systems, can’t catch a break from the United States Department of Justice. In addition to the fallout from being declared a monopoly for search and browsers, an entirely separate case has just found Google guilty of monopoly practices in web advertising. It’s a huge blow.

US District Judge Leonie Brinkema found Google guilty of violating the Sherman Antitrust Act by “willfully acquiring and maintaining monopoly power in the open-web display publisher ad server market and the open-web display ad exchange market.” Here’s a PDF of the ruling, via The Verge. It’s the conclusion of a case brought by the federal government and eight states over two years ago.

Though Google competes in dozens of categories—from manufacturing its own phones to providing “big iron” data to some of the world’s biggest companies—advertising is arguably its most important business. Ads keep much of the web profitable and allow Google to provide its primary search engine for free, in addition to other services like Gmail, Google Docs, YouTube, etc. According to Statista, Google reaped over 250 billion US dollars from advertising in 2024, and Google owns 80 percent of the search market worldwide.

The determination that Google is operating an illegal monopoly—the second such determination from the US DOJ in two years—could be devastating to its business. The punishment or remedy currently isn’t known, but previous corporations found guilty of intentional monopoly behavior have been broken up or forced to divest themselves of portions of their business. That’s one possible end to the ongoing case: Google might be forced to sell or otherwise dispose of the Chrome browser.

And the United States isn’t the only country with a bone to pick. In an earlier news story today, Google is facing a possible $6.6 billion USD fine in the United Kingdom, again, for violating its market-leading position in search. It’s only the lastest problem the company has had in the region, as the European Union has been cracking down on Google for advertising and other monopoly violations for over a decade.

It’s possible, though far from certain, that the US federal government might force Google to abandon both the advertising and browser markets in 2025. That would be absolutely devastating for the big G, though it has plenty of other assets that would allow it to survive in a diminished capacity. But full divestment is only one of many ways both cases could shake out, and Google will undoubtedly exhaust every option in its legal arsenal to mitigate the damage. It’ll be months, at least, before we see a full conclusion to either story.