DOJ: Google must be split up to fix its ad monopoly

A US judge is weighing whether to break up Google's adtech business in the closing arguments of the antitrust trial between the tech giant and the US Department of Justice (DOJ) on November 21.

In the remedies phase of the trial, US district court judge Leonie Brinkema pressed the DOJ on how quickly a forced divestiture could take place as she considers remedies to fix Google's abuse of its dominance in adtech. She raised concerns over the impact of Google's expected appeal that would significantly delay structural remedies in what is likely to be one of the most significant government interventions in the ad market.

 “The kind of request you are making most likely would not be as easily enforceable while an appeal is pending,” Brinkema told DOJ lawyers, suggesting that any hesitation on ordering a remedy would likely delay divestiture for years. She noted that Google is "in an impossible situation," given that publishers and rival adtech players are tacking on more damage suits against the company.

The DOJ has urged the court to force Google to sell AdX, the exchange where publishers pay a 20% fee for real-time auctions that serve display ads to users when they load web pages.

DOJ lawyer Matthew Huppert argued that only the equivalent of a forced sale would deliver "a brighter, more competitive future for the open web," adding that the remedy must "eradicate Google's illegally acquired monopolies root and branch." Google countered that a divestiture would be disruptive and technically complex, warning that it would ultimately hurt consumers rather than help them. 

"Lawfully acquired monopoly power is the foundation of the American economy,” Karen Dunn, Google's lead counsel, told the court. She argued that targeted behavioural remedies, including increased data transparency, are less risky than carving up Google's ad business. 

Brinkema previously ruled in April that Google unlawfully monopolised its publisher ad server and ad exchange, which are critical layers of the open-web ad-stack. This gave the company significant control over how ads are bought and sold online. She found that Google had wilfully acquired and maintained its monopoly by adopting policies that were not in the publishers' best interests.

The other major case of similar magnitude was the 1990s lawsuit against Microsoft, which was accused of monopolising just two markets: PC operating systems and web browsers.

In an adjacent case against Google, in August 2024, Judge Amit Mehta issued a sweeping ruling in U.S. v. Google (Search)and called Google "a monopolist", and that effectively, "Google controls about 90% of the online search market and 95% on smartphones."

The ongoing trial, which is expected to conclude in early 2026, is part of a wider US antitrust campaign against big tech. Last week, Meta secured a major victory when a federal judge rejected the Federal Trade Commission’s (FTC) bid to force the company to divest Instagram and WhatsApp. The judge found the FTC had failed to prove that Meta holds a social media monopoly.