What does the Justice Department want?

The DOJ wants to strip Google of the advantages it gained through years of consolidation. The government’s proposal involves breaking the monopoly’s dominance through a three-phase structural remedy. First, level the playing field by forcing Google to give competing ad exchanges and servers real-time access to AdX bidding data through Prebid. Next, a second phase would involve requiring Google to open-source its auction logic — the brains behind its DFP ad server. The third phase would involve full divestiture of both DFP and AdX, with both being put under supervision of a court-appointed trustee and the DOJ getting approval of the ultimate buyers.

Once divested, Google would be banned from running an ad exchange for a decade. Another part of the government’s proposal would require Google to place 50% of net revenues from AdX and DFP into escrow until the divestitures are complete. One potential use of the funds would be to support the industry’s transition efforts or help publishers cover switching costs. The proposal also calls for Google to share DFP data with an independent auction.

Why this approach?

Because a rulebook won’t cut it. The DOJ argues that behavioral remedies — with a list of what Google can and can’t do — won’t outmaneuver a company that’s made a habit of bending the rules. Google’s track record, the DOJ said, shows it knows exactly how to game any system that relies on checks and balances. That’s why the agency is pushing for structural remedies rather than not-surface level fixes. 

At the heart of Google’s dominance is its ad server and exchange — critical infrastructure that determines which ads appear, where and who gets paid. Leaving that machinery under Google’s control, the DOJ said, is simply too risky. By open-sourcing the logic behind it, others might get a fighting chance, but anything less than that won’t fix the problem, just rebrand it.

What does Google want?

Not surprisingly, Google would prefer to skip the breakup. Instead, the company is proposing giving competitors real-time access to AdX data via Prebid. It is also willing to scrap its Unified Pricing Rules (UPR) for open web and display ads — rules that since their 2019 rollout, have drawn ire from publishers for limiting flexibility and favoring Google’s stack. In a nod to fairer competition, Google said it would formally commit to never reintroducing its first-look or last-look advantages in open web auctions. 

While Google argues that’s enough remedy to level the playing field, critics argue these offers are more patchwork than solution, and fall short of truly leveling the field. The DOJ itself argued in court that behavioral remedies won’t be sufficient.

“The DOJ conceded Google’s proposed ad tech remedy fully addresses the court’s decision on liability,” Lee-Anne Mulholland, Google’s vp of Regulatory Affairs, said in a statement on Friday. “The DOJ’s additional proposals to force a divestiture of our ad tech tools go well beyond the court’s findings, have no basis in law, and would harm publishers and advertisers.”

Why is Google offering to make these concessions specifically?

This approach would allow Google to use strategic pressure valves meant to show goodwill without ceding real structural power. Opening up data access and overhauling pricing rules could earn Google courtroom points while keeping its core ad tech stack intact.

While Google has portrayed the case as focused on solving past problems, industry experts also see a need to address current and future problems. Meanwhile, others wonder where there’s meaningful competition to Google Ad Manager (GAM) will actually come from even if Google’s forced to divest. 

Is a breakup likely?

It’s too early to call but not as far-fetched as it once seemed. Not so long ago the idea that Google might be forced to divest parts of its ad tech empire felt like a long-shot. But recent developments in the DoJ’s antitrust case have changed the tone. What was once theoretical is now inching toward plausible. A structural breakup isn’t guaranteed, but it’s no longer a fringe scenario.

Structural remedies like divesting DFP and/or AdX appear to be the most likely and most effective way to address the underlying imbalance, said Index Exchange CEO Andrew Casale.

“True competition can only thrive when the market is no longer shaped by entrenched advantages,” Casale said. “… Behavioral fixes may offer short-term relief, but on their own, fall short of resetting the dynamics of the market.”

During the hearing, Judge Brinkema expressed interest in the proposal, raising the idea that Google divesting AdX would help remedy the whole thing. Google’s lawyers argue that the spin-out is too complex and too unfeasible, but it’s too early to know whether the court would deem it necessary and what it’d look like in practice.

The judge also expressed concern about whether publishers might face potentially high “switching costs” when moving to a different ad server. However, some supporters of the DOJ’s proposal think open-sourcing the final auction logic would not only make it easier for publishers to switch, but also lower barriers to entry in the ad server market, which could help prevent future dominance by any single player.

It’s too soon to tell how the ad tech case and the search case will impact each other. For now, the DOJ has been keen to make the distinction that they’re separate cases. However, one of the DOJ’s proposals for the adtech case is banning Google from using first-party data from Google products — such as YouTube and Chrome — to prevent it from advantaging its own ad tools.

Even if Google’s forced to divest of AdX, building an ad server or SSP remains time- and cost-prohibitive for most publishers, making new challengers unlikely to emerge quickly, said Matt Barash, Chief Commercial Officer at the creative AI platform Nova. One possibility is Magnite, which is advancing a unified platform with SpringServe and its exchange. Another he mentioned is Mediaocean, which may move further into the sell-side market following its acquisitions of Innovid and Flashtalking.

“We may see a surge of companies trying to develop alternative ad servers but the real market opportunity by the time remedies take effect will be in video more so than display,” Barash said. “By the time things are settled the open web opportunity will be in the rear view mirror.”

What next?

The remedies phase of the DOJ–Google adtech trial will unfold over the next several months, beginning with the filing of remedies proposals and followed by factual and expert discovery. After several rounds of responses, expert reports, and reply briefs, the trial is set to commence on September 22, 2025. This timeline lays out a detailed process for both sides to present, challenge, and refine their proposals before the court makes a final decision. Here are some key dates:

June 30, 2025: Factual discovery closes

July 7, 2025: Expert reports due

July 28, 2025: Opposition expert reports due

August 27, 2025: Expert discovery closes

Sept. 5, 2025: Proposed orders filed

Sept. 19, 2025: Final responses to opposing proposals due

Sept. 22, 2025: Remedies trial begins