In a federal courtroom in Alexandria, Virginia, on Friday, closing arguments in the U.S. Department of Justice’s antitrust remedies trial against Alphabet Inc.’s Google concluded with Judge Leonie Brinkema expressing deep reservations about forcing a breakup of the tech giant’s advertising technology business. The hearing, which wrapped up the latest chapter in a saga that could reshape digital advertising, highlighted the tension between eradicating monopolistic practices and the practical challenges of structural remedies in a fast-evolving tech landscape.

The DOJ has pushed aggressively for divestitures, including Google’s AdX exchange, to dismantle what it calls an illegal monopoly in publisher ad servers and ad exchanges. Google, meanwhile, countered with behavioral remedies, arguing that a forced sale would harm innovation and efficiency without restoring competition. Judge Brinkema’s questions during the arguments suggested skepticism toward the government’s more draconian proposals, particularly amid Google’s likely appeal.

Judge’s Wary Stance Emerges

“I’m very concerned about how a breakup would work while Google likely appeals,” Judge Brinkema remarked, according to live updates from observers in court. Her comments, reported by The Verge, underscore the procedural hurdles: any remedy would face years of appeals, potentially leaving the market in limbo. The judge also probed the feasibility of spinning off AdX, questioning whether it could operate independently given its deep integration with Google’s ecosystem.

The DOJ opened by framing the case as a battle for the open internet’s future. “Google systematically dismantled the competitive process in two ad tech markets,” prosecutors argued, demanding not just regulation but eradication “root and branch,” as noted in real-time posts on X by antitrust watchers like Vidushi Dyall. They proposed divesting AdX, ending Google’s last-look advantage, and requiring data sharing to level the playing field for rivals like PubMatic and Magnite.

Google’s defense, led by lawyers emphasizing innovation risks, proposed lighter touches: ending auctions for publisher tools and improving transparency. “A breakup would stifle the very competition the DOJ seeks,” they contended, per The New York Times coverage of the proceedings.

Roots of the Ad Tech Monopoly

This remedies phase follows Judge Amit Mehta’s April ruling that Google maintained illegal monopolies in open-web display ad tech—a victory for the DOJ after a trial that exposed internal emails and strategies. Mehta found Google controlled over 90% of publisher ad servers via DoubleClick for Publishers (now Google Ad Manager) and dominated ad exchanges with AdX, squeezing publishers and advertisers alike.

Evidence from the trial, unsealed documents, and expert testimony painted Google as a gatekeeper that acquired rivals like DoubleClick in 2008 for $3.1 billion, then integrated tools to favor itself. Publishers testified to dependency: switching costs were prohibitive, and Google’s tools offered unmatched scale. As Reuters reported earlier, closing arguments were delayed to November 21 to allow fuller briefing.

The stakes are immense: Google’s ad tech generates tens of billions annually, part of its $350 billion-plus ad revenue empire. DOJ economists estimated harms exceeding $20 billion yearly, justifying remedies up to divestiture.

DOJ’s Aggressive Remedy Blueprint

The government’s proposed final judgment, a 60-page document detailed by X user Jason Kint, calls for structural changes: divest AdX within six months, ban Google from re-entering the exchange market for 10 years, and unwind exclusive deals. Behavioral fixes include real-time data access for competitors and ending revenue-sharing contracts that lock in publishers.

“This is about the lifeblood of the internet,” DOJ lawyers urged, echoing Kint’s analysis. They cited Texas’s parallel case, where experts pegged penalties at $29 billion, and prior exhibits showing Google deleting chats under litigation hold—a spoliation issue Judge Brinkema may revisit.

In court, DOJ reminded that antitrust law demands effective relief, not half-measures. Rivals like The Trade Desk and Criteo stand to gain from forced openness, potentially injecting billions into competition.

Google’s Counteroffensive and Market Realities

Google’s 50-page response favors conduct rules: no bundling of tools, third-party access to AdX auctions, and ending publisher revenue shares over 15%. “These fixes address liability without disrupting the ecosystem,” per their filing, as covered by PPC Land. They warn divestiture would create a “stranded” AdX, unable to compete without Google’s demand-side integration.

Industry insiders on X, including Ari Paparo, noted the judge’s skepticism post-arguments: “Enough to sway me it’s not going to happen.” PubMatic and Magnite stocks dipped slightly, reflecting tempered expectations for immediate divestiture.

Google points to declining market share—from 91% to 82% in ad serving per their data—and growth in alternatives like Amazon’s DSP as evidence markets are contestable.

Broader Antitrust Echoes

This trial parallels the search monopoly case, where Judge Mehta ordered no breakup but behavioral curbs; appeals loom there too. In ad tech, Texas AGs join DOJ, amplifying pressure. European probes and private suits add global scrutiny.

X posts from Paul Glenchur predict “no divest” but fixes benefiting sell-side platforms. Megan Gray quipped the judge had “no questions (and no bladder),” signaling DOJ’s pitch fell flat.

The ruling, due in months, could set precedents for Big Tech breakups amid political shifts—Trump’s FTC chair may influence enforcement.

Path Forward Amid Uncertainty

Whatever Judge Brinkema orders faces Supreme Court review, given the novel remedies. Ad tech execs brace for change: more data portability, open auctions, or worst-case divestiture by 2027 post-appeals.

Arielle Garcia of the DOJ team recapped on X: “This case is about the future of the open internet.” Publishers like News Corp, who sued separately, watch closely, hoping for relief from 30-40% ad revenue funneled to Google.

For industry insiders, the real intrigue lies in execution: Can behavioral remedies restore choice, or does monopoly inertia demand surgery? The ad tech stack—SSPs, DSPs, exchanges—hangs in balance.