The US Department of Justice (DOJ) is back in court in Alexandria, Virginia, seeking structural fixes to Google’s ad-tech stack.

The remedies trial is expected to run for about two weeks.

The case arrives shortly after a separate Google search ruling delivered relatively modest remedies.

As Channel News reported, there was no forced Chrome divestiture, and Google can still pay for distribution under non-exclusive deals.

That puts fresh attention on whether its ad-tech arrangements will face a tougher verdict.

The court has already found Google to be a monopolist in two ad-tech markets and to have illegally tied its AdX exchange to its DFP publisher ad server.

In plain English, that means DFP – DoubleClick for Publishers, now part of Google Ad Manager – favoured AdX, Google’s Ad Exchange.

Publishers got the best bids, speed, and data only by routing impressions to AdX, with worse results on rival exchanges.

Google’s guilty – the only question now is what remedy is applied

The remedies phase will decide how to unwind the competitive harm.

The DOJ is pushing to force Google to sell AdX.

It also wants Google to open-source DFP’s final-auction logic to boost transparency.

If those steps don’t restore competition, the government wants the option to push for a DFP divestiture as well.

Google is arguing that these drastic steps aren’t necessary.

Instead, it’s offering to provide real-time access to AdX bid amounts for rival publisher ad servers, the deprecation of Unified Pricing Rules, and commitments not to use ‘First Look’ or ‘Last Look’ advantages.

It also backs broader data-export portability for publishers.

Testimony will be provided by publishers, ad-tech executives and economists.

Whatever Judge Leonie M. Brinkema decides, Google can’t appeal the liability ruling until she issues the remedies. If she orders a breakup, that would then go through a lengthy appeals process.

The stakes are high for all involved.

AdX is the central plumbing for open-web display advertising.

Forcing a sale—or prying open DFP’s auction code—would reshape how impressions are routed, how bids are ranked, and how revenue is split between intermediaries and publishers.

Supporters of significant change argue that more competition and transparency could lift publisher yields and reduce conflicts of interest inside vertically integrated stacks.

However, sceptics warn that ripping apart Google’s tightly coupled systems could add latency, complexity and new costs, with uncertain benefits for smaller sites.

After a narrower win in search, this case gives the DOJ another swing at changing Google’s incentives in a core market.

The court has already determined that Google broke the law.

The question now is what remedies will restore competition without breaking the web in the process.