The U.S. Department of Justice and 17 states sued Google in the Eastern District of Virginia, alleging it monopolized website advertising technology. The court found Google liable in April 2025 and, on September 2, 2026, rejected divestiture of its AdX exchange in favor of behavioral remedies. On October 2, 2026, the parties filed proposed final judgment terms with disputed points bracketed, and Google has said it will appeal the liability ruling.
Latest development Oct 2, 2026
On October 2, 2026, the U.S. Department of Justice (DOJ), 17 states, and Google filed proposed final judgment terms with bracketed alternative language on unresolved issues. These include the AdX-Prebid interoperability deadline (the DOJ proposes six months, Google 12), the geographic scope of remedies, data rights, and the compliance monitor’s authority. No final judgment has been entered.
Why it matters
The court declined to order a break-up, as the court in the separate Google search case also did. The final decree will set how Google’s ad server and exchange must work with rival tools, affecting publishers, advertisers, and competing ad tech firms.
Background
The U.S. Department of Justice (DOJ) and 17 states sued Google LLC in the U.S. District Court for the Eastern District of Virginia in January 2023, seeking structural relief. The suit targeted Google’s dominance of the “ad tech stack”: the publisher ad server (DFP), the ad exchange (AdX), and advertiser buying tools that sit between websites and advertisers. Judge Leonie M. Brinkema held a three-week bench trial on the court’s “rocket docket” in September 2024. On April 17, 2025, she ruled that Google willfully monopolized the open-web publisher ad server and ad exchange markets and unlawfully tied DFP to AdX. She rejected the government’s separate advertiser ad network market.
The remedies trial ran from September 22, 2025, to closing arguments on November 21, 2025. The government sought divestiture of AdX, backed by open-sourcing of auction logic and, if needed, a phase-out of DFP. Google offered behavioral commitments such as Prebid interoperability and separate contracting for DFP and AdX. At closings, Judge Brinkema pressed the DOJ on the “commercial reality” of a forced sale when no buyer had been identified. Any large acquirer would face its own antitrust review, and the judge called for a concrete, workable order.
On September 2, 2026, Judge Brinkema rejected all three structural remedies: AdX divestiture, open-sourcing of DFP’s final auction logic, and contingent divestiture of the DFP Remainder. She instead adopted most of the parties’ proposed behavioral remedies as modified by the court. She filed the memorandum opinion under seal and ordered the parties to file a joint proposed final judgment within 30 days, by about October 2, 2026.
On September 16, 2026, the court unsealed the 106-page opinion. It requires Google to build API integrations connecting AdX and DFP to Prebid and to submit AdX bids to rival publisher ad servers on the same terms as DFP. Google must also provide data portability to publishers and operate under a compliance monitor and technical committee for six years, with about 12 to 15 months to implement the interoperability measures. On October 2, 2026, the parties filed proposed final judgment terms with bracketed alternatives on implementation deadlines, geographic scope, data rights, and monitor authority. Google has said it will appeal the liability ruling.
Timeline 9 events
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FilingParties file proposed final judgment terms with bracketed alternatives
The DOJ, 17 states, and Google disagreed on implementation deadlines, geographic scope, data rights, and monitor authority. The DOJ seeks six months for AdX-Prebid interoperability, while Google seeks 12.
DOJ seeks 6 months, Google 12, to open its ad exchange to rivalsDOJ wants AdX open to Prebid in six months, Google asks for twelve
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JudgmentCourt unseals full remedies opinion detailing behavioral remedies
The opinion requires Google to connect AdX and DFP to Prebid and submit AdX bids to rival ad servers on DFP’s terms. Google must also give publishers data portability and accept a six-year compliance monitor and technical committee.
The Court Just Unsealed Judge Brinkema's Remedies Decision In The Google Ad Tech Antitrust CaseGoogle's ad-tech remedies are finally public: Here's exactly what publishers getDepartment of Justice Again Wins Substantial Relief Against Google
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OrderCourt orders joint proposed final judgment within 30 days
Judge Brinkema ordered the DOJ and Google to jointly file a proposed final judgment specifying implementation of the behavioral remedies within 30 days, by approximately October 2, 2026.
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JudgmentBrinkema rejects structural remedies and orders behavioral remedies
The court rejected the DOJ’s three structural remedies: AdX divestiture, open-sourcing of DFP’s final auction logic, and contingent divestiture of the DFP Remainder. It adopted most of the parties’ proposed behavioral remedies as modified and filed the opinion under seal.
Judge rejects AdX divestiture in DOJ ad tech caseCCIA's Response to Court Ruling on Google Ad Tech Remedies in DOJ Antitrust Case
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HearingParties deliver closing arguments in remedies trial
Judge Brinkema questioned the absence of an identified buyer and the workability of structural relief, and said a decision might come “maybe next year.”
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HearingDOJ and Google open remedies trial
The DOJ pressed for AdX divestiture and open-sourced auction logic. Google offered behavioral remedies including Prebid interoperability.
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JudgmentCourt holds Google liable for ad tech monopolization
The court found willful monopolization of the publisher ad server and ad exchange markets and unlawful tying of DFP and AdX. The advertiser ad network claim failed.
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HearingCourt holds liability bench trial in Alexandria
The three-week trial before Judge Brinkema ran from September 9 to 27, 2024. Closing arguments followed on November 25, 2024.
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FilingDOJ and states sue over Google’s ad tech stack
The complaint targeted Google’s control of the publisher ad server, ad exchange, and buy-side tools and sought structural relief.
Experimental AI forecast
How it is madeHow will the Fourth Circuit rule on Google’s appeal of the ad tech liability judgment by September 30, 2028?
- Fourth Circuit affirms Google liability40%
- Still pending on September 30, 202835%
- Liability or remedy partly vacated14%
- Appeal ends without a merits ruling6%
- Fourth Circuit vacates liability5%
- Resolves by
- Sep 30, 2028in 23 months
- Record confidence
- Medium
The Fourth Circuit most likely affirms Google’s ad tech liability (40%), though a ruling may not arrive before September 30, 2028 (35%). Liability rests on detailed bench-trial findings on market definition and tying that appellate courts review deferentially.
How it resolves. Resolves on the first Fourth Circuit panel decision on the merits of Google’s appeal from the final judgment in 1:23-cv-00108 (E.D. Va.), as shown on the public docket or in the published opinion. “Affirms” means the panel upholds liability on both the monopolization and tying claims and leaves the remedy order materially intact. “Partly vacated” means the panel upholds at least one liability holding but reverses or vacates another liability holding or a material part of the remedy, including any remand. “Vacates liability” means the panel reverses or vacates all liability holdings. “Ends without merits ruling” means no appeal is filed, or the appeal is dismissed, withdrawn, or resolved by settlement before a panel merits decision. “Still pending” means none of these has occurred by September 30, 2028. Rehearing or Supreme Court review after the panel decision does not change the outcome.
Reasoning
Starting point. Federal appeals of government civil antitrust judgments after bench trials, reviewed largely for clear error on facts: Federal courts of appeals reverse civil judgments in roughly 10% to 15% of appeals decided on the merits. Bench-trial fact findings, including market definition, get deferential review. Complex antitrust appeals in the Fourth Circuit often take 12 to 20 months from notice of appeal to decision.
Federal appellate courts reverse roughly 10% to 15% of civil judgments on the merits, and bench-trial fact findings receive clear-error deference. That favors affirmance, but the tying holding and market definition give Google its strongest grounds, so a partial vacatur stays plausible at 14%. Timing is the main constraint because no final judgment has been entered and the October 2, 2026, proposed judgment still brackets disputes on deadlines, scope, data rights, and monitor authority. Entry likely comes late 2026 or early 2027, followed by briefing, argument, and a decision that could slip past September 30, 2028. The behavioral remedy lowers Google’s incentive to settle, though a negotiated end or dropped appeal remains a small possibility. Nothing in the October 2 filing moved any outcome by five points or more since the September 24, 2026, forecast, because it only confirmed expected disputes over decree terms.
No final judgment entered yet, which delays the appeal clock · Clear-error deference to bench-trial market and tying findings · Tying holding is Google’s most contestable appellate issue · Behavioral remedy reduces Google’s pressure to settle · Possible DOJ cross-appeal on rejected structural remedies
Generated automatically by Claude Opus 5.5 on Oct 8, 2026 from this case’s record on this site, and published without editorial review. The probabilities are the model’s judgment, not measured frequencies, and they are scored publicly as cases resolve. Not legal or investment advice. How the forecasts are made
Disclosure: Anthropic, which makes the model that wrote this forecast, competes with or has commercial ties to a party to this case.