A U.S. judge rejected a forced sale of Google’s AdX exchange and ordered changes to its ad systems aimed at giving publishers more choices and rival services greater access.
In an April 17, 2025, liability ruling, U.S. District Judge Leonie M. Brinkema found that Google unlawfully monopolized the worldwide markets for open-web display publisher ad servers and ad exchanges. The court also found that Google unlawfully tied its DFP publisher ad server to AdX. It rejected a separate claim concerning advertiser ad networks.
DFP manages publishers’ ad inventory, while AdX is an exchange where advertisers bid for it. The court found that linking the products limited publishers’ options and hindered competitors. Its liability opinion said AdX maintained a 20% take rate for more than a decade. It also cited a calculation estimating that Google served 91% of publisher ad server impressions worldwide in 2022.
In the Sept. 2 remedies opinion, Brinkema declined the Justice Department’s request to sell AdX. Instead, she ordered Google to make DFP and AdX work with Prebid, a tool for soliciting competing offers, and required AdX to submit real-time bids to rival publisher ad servers.
The requirements also cover publisher access to data, bidding restrictions and independent oversight, the Justice Department said. They aim to make it easier for publishers to change providers and for competing services to bid for their ad inventory.
Brinkema rejected a proposal to open-source DFP’s final auction logic and a provision for a possible later sale of the remaining DFP business. Associate Attorney General Stanley E. Woodward Jr. called the outcome a significant win for the department’s competition efforts. Before the remedies trial, Google Vice President of Regulatory Affairs Lee-Anne Mulholland said the company believed separating its tools would reduce publishers’ ad revenue and raise advertisers’ costs.
Brinkema directed the parties to submit a joint proposed final judgment within 30 days of Sept. 2, identifying any disputed terms. The judgment is set to apply worldwide for six years, with a possible extension if its requirements remain unmet. Most provisions take effect 60 days after the court enters it.
