Unsealed Google ad tech ruling: AdX stays, a six-year monitor arrives

The breakup that antitrust hawks wanted is not in the PDF. The six-year leash is. After a redaction window in which neither side asked to black anything out, Judge Leonie Brinkema’s full 106-page remedies opinion in the US ad tech case against Google is public. Google keeps its AdX exchange. It does not keep the quiet power to weld that exchange to its publisher ad server, shut rivals out of equivalent bids, or treat Prebid as someone else’s problem.

What Google must rebuild

The core order snaps the default link between DoubleClick for Publishers (DFP) and AdX. Publishers using DFP no longer have to route through AdX. AdX must bid into rival publisher ad servers on terms that are functionally equivalent to what DFP receives, not a checkbox integration that looks open and performs worse. Google must also build API interoperability connecting both AdX and DFP to Prebid, the open-source header-bidding stack publishers adopted precisely to escape Google’s pipes.

Transparency requirements cut into the auction black box. Google has to share real-time winning and losing bid data with publishers and publish documentation explaining how DFP selects winners, including pricing and bid adjustments. The court rejected a DOJ push to open-source DFP’s auction code outright. On the buy side, AdWords may no longer bid directly into DFP or favor Google’s own ad tech tools. DV360 escaped similar limits because the court found the government never tied it tightly enough to the proven misconduct.

Six years, global, and watched

Oversight runs for six years, the term Google proposed, not the fifteen years the Justice Department and joining states sought. AdExchanger reports a court-appointed technical monitor with full access to Google staff, systems, and source code. The remedies apply worldwide. Brinkema rejected Google’s bid to cabin them to the United States, writing that a global judgment means product changes consistent across regions. After the parties submit proposed final judgments (due early October per AdExchanger), the requirements take effect about 60 days from entry of the official order.

The DOJ’s January 2023 case argued Google illegally maintained a monopoly in open-web display advertising by tying DFP to AdX and using auction tactics such as first look, last look, and unified pricing rules to blunt header bidding. A liability finding followed trial. Remedies were the remaining fight. Brinkema’s September 2 public order already said AdX would not be sold. The unsealed opinion explains why behavioral surgery won over structural excision, citing appeal delay, disruption to publishers that depend on Google’s stack, and harm to smaller businesses.

Distrust without divorce

Courthouse News and TNW both highlight the judge’s own skepticism. Brinkema referred to a “lack of trust that Google will comply with an order from this court,” yet still chose monitoring and interoperability over a forced AdX sale that publishers currently pay a 20 percent fee to use. Critics such as the Open Markets Institute called the outcome an abdication. European regulators have argued only a breakup would fix the stack.

The odd result is a remedy built on distrust. Google keeps the crown jewel exchange. It loses the ability to treat that exchange as a private club, and it gains a technical chaperone with source-code keys for half a dozen years. Whether that pries open the market, or merely teaches Google how to comply on paper, is now an empirical question the monitor is paid to watch.