Judge Refuses to Break Up Google’s Ad-Tech Business Despite Illegal Monopoly Ruling

A federal judge on Wednesday rejected the Justice Department’s effort to force Google to sell a key part of its online advertising business, allowing the technology giant to keep its AdX advertising exchange despite an earlier ruling that Google illegally monopolized parts of the digital advertising market.

U.S. District Judge Leonie Brinkema of the Eastern District of Virginia rejected the Justice Department’s request to force Google to sell AdX, its advertising exchange for buying and selling online ad space. Instead, she imposed restrictions on how Google can operate the business to limit anticompetitive conduct and give rivals more room to compete. The full ruling will remain under seal for 14 days while the court removes confidential business information.

The decision leaves intact Brinkema’s April 2025 finding that Google violated federal antitrust law. She concluded that the company unlawfully acquired and maintained monopoly power in two markets involving technology used by online publishers: publisher ad servers and advertising exchanges.

The Justice Department had sought a far more aggressive remedy. It argued that Google should be required to sell AdX because the company could not be trusted to operate the exchange after years of anticompetitive conduct.

Brinkema stopped short of taking that step.

Google welcomed the decision, saying a forced sale would have disrupted tools used by businesses and publishers. The Justice Department said it was pleased that the court had ordered substantial relief and was evaluating its next steps.

The ruling represents an important distinction in antitrust law. Finding that a company illegally maintained a monopoly does not automatically require a court to break up the business. Once a violation has been established, a judge must separately determine what remedy is needed to restore competition and prevent similar conduct in the future.

A forced sale is among the most aggressive options available. Courts can instead impose restrictions on how a company operates, require it to give competitors greater access to its systems, or prohibit business practices that helped maintain the monopoly.

Google proposed changes that included giving competitors access to real-time bidding information. Brinkema accepted behavioral remedies, although the full scope of those requirements will not become public until the court releases its redacted opinion.

The case concerns the largely invisible technology behind advertising on millions of websites.

Publisher ad servers allow websites to manage the advertising space available on their pages. Ad exchanges operate as electronic marketplaces where that advertising inventory can be sold through automated auctions that occur almost instantly as a webpage loads.

Google operates products on multiple sides of that process.

AdX is its advertising exchange. Publishers using the service generally pay Google a 20% fee when advertising is sold through the exchange. Google also operates technology that publishers use to manage their advertising inventory.

The Justice Department and a coalition of states sued Google in 2023, alleging that the company used its control over those interconnected products to suppress competition in the market for online advertising technology.

After a three-week trial, Brinkema ruled in April 2025 that Google had unlawfully tied publishers using its ad server to its AdX exchange. She found that the practice deprived rivals of opportunities to compete and harmed publishers as well as consumers who rely on information available through the open internet.

The government did not prevail on every allegation. Brinkema rejected a separate claim that Google illegally monopolized the market for advertising networks used by advertisers.

The case then moved to a second phase to determine how Google’s antitrust violations should be addressed.

During the remedies trial, Justice Department lawyers argued that restrictions on Google’s future behavior would not be enough. They sought divestiture of AdX, contending that removing the exchange from Google’s control was necessary to restore competition.

Google argued that separating AdX from the rest of its advertising technology would be technically difficult and could create a lengthy transition that would harm customers.

Brinkema ultimately sided with Google on the breakup question while still imposing restrictions on the company’s conduct.

The result adds to a developing pattern in the federal government’s campaign against the largest U.S. technology companies.

Another federal judge previously found that Google illegally monopolized the online search market but rejected a Justice Department request that would have required the company to sell its Chrome browser. A federal court also rejected the Federal Trade Commission’s effort to force Meta to divest Instagram and WhatsApp, although the Meta case differed because the government failed to establish that Meta currently held the monopoly it alleged.

Wednesday’s ruling is particularly significant because Google did not escape liability. A federal court has already determined that the company violated antitrust law in the advertising technology market. The dispute was over whether that misconduct justified dismantling part of its business.

For federal regulators, the outcome shows the difficulty of moving from proving illegal monopoly conduct to obtaining a court-ordered breakup.

For Google, the ruling removes one of the most severe potential consequences of the case while leaving the company subject to court-imposed restrictions and an existing finding that it violated federal antitrust law.

The dispute also is not necessarily finished.

Google has indicated that it intends to challenge the underlying monopoly ruling, while the Justice Department said Wednesday that it is considering what steps to take following the remedies decision. The full effect of Brinkema’s order will become clearer once the detailed opinion is released after the confidential portions are redacted.