A federal court has declined to force Google to sell its ad exchange or open-source its auction logic in a landmark US antitrust ruling.
Judge Leonie Brinkema of the Eastern District of Virginia unsealed a 106-page remedies opinion in United States v. Google, the Justice Department’s ad tech monopolization case.
The court found structural relief “neither realistic nor needed,” instead adopting detailed behavioral remedies targeting the specific conduct it found unlawful.
This marks the second time within a year that a federal judge has rejected government calls to break up Alphabet (GOOGL), following Judge Amit Mehta’s ruling in the separate Search monopoly case.
In April 2025, Judge Brinkema held that Google violated Sections 1 and 2 of the Sherman Act by monopolizing two worldwide markets for open-web display advertising.
Google’s publisher ad server product DFP and its ad exchange AdX were both found to be central to the monopolization, with both products originally entering Google’s portfolio through acquisition.
The core violation identified by the court was a tie between DFP and AdX, which Google combined under a single platform called Google Ad Manager in 2018.
Under the court’s order, Google may not enforce any policy or contract term that ties DFP to AdX, and it may not recreate that tie through other means.
First Look, Last Look, and Unified Pricing Rules are all prohibited for indirect transactions, with publishers regaining the ability to set different price floors across different exchanges.
According to the plaintiffs’ own expert, eliminating Unified Pricing Rules alone would cut AdX’s 20 percent take rate to roughly 16.6 percent, bringing it in line with rivals.
Google must also build integrations allowing Prebid, the open-source header bidding platform, to solicit real-time AdX bids for all indirect open-web display inventory.
Publishers will be permitted to export their DFP data to competing ad servers and obtain AdX bid data, including losing bids, under the new framework.
A Monitor with access to Google’s documents, employees, and source code will oversee compliance, supported by a Technical Committee and an Internal Compliance Officer.
The final judgment will run for six years, apply worldwide, and take effect 60 days after entry, with parties given 30 days to submit a joint proposed final judgment.
The court’s rejection of divestiture relied on the DC Circuit’s decision in Microsoft, which requires a “significant causal connection” between unlawful conduct and the monopoly, a more demanding standard than liability alone.
The plaintiffs never identified a viable buyer for AdX, which is deeply integrated with Google infrastructure spanning more than 100 million lines of code.
Comparable-sized technology migrations have taken five to eight years to complete, while behavioral remedies under the order can be fully implemented within 15 months.
The proposal to open-source DFP’s auction logic failed partly because a single DFP function depends on a daily computation running ten hours across 4,000 machines.
The court was direct in addressing the government’s underlying rationale, concluding it came down to distrust of Google and “an unrealistic desire for certainty,” neither of which can justify a breakup.
Judge Brinkema described the government’s divestiture proposals as “a poor fit for this case” and adopted Judge Mehta’s assessment that a breakup would be “incredibly messy and highly risky.”
Both judges also emphasized that artificial intelligence is actively reshaping the markets under examination, adding further complexity to any long-term structural intervention.
Google remains exposed to contempt sanctions and a growing number of private lawsuits, which the court described as “swords of Damocles” ensuring continued compliance with its order.
Appeals from both sides are widely expected, meaning the final shape of Google’s obligations in the ad tech market could yet change significantly.