Google's September trial could force breakup of adtech empire

The remedies trial is set for September 22, following a federal judge’s April ruling that Google illegally monopolised critical segments of the digital advertising market

by e4m Staff
Published: May 3, 2025 12:36 PM | 2 min read

The U.S. Department of Justice (DOJ) has dramatically escalated its antitrust battle with Google, seeking a court order to break up the tech giant’s advertising technology business-a move that could reshape the $2 trillion digital ad industry. The remedies trial is set for September 22, following a federal judge’s April ruling that Google illegally monopolised critical segments of the digital advertising market.

At the heart of the DOJ’s case is Google’s dominance over the technologies that connect advertisers with online publishers. The government argues that Google’s control over both the ad exchange (which matches buyers and sellers of ad space) and publisher ad servers (which manage ad inventory for websites) has left “90 percent of publishers beholden to them,” a situation DOJ lead attorney Julia Tarver Wood called “frankly, too dangerous”.

The DOJ is pushing for a phased remedy: first, Google would be required to share real-time bidding data with competitors, followed by the full divestiture of its publisher ad server and ad exchange businesses.

Judge Leonie Brinkema’s April ruling found that Google had improperly tied the use of its ad exchange to its publisher ad server, harming competition and adversely affecting publishers and internet users. This follows last year’s landmark decision that Google also held an illegal monopoly in online search, marking the most significant antitrust judgment in tech since the Microsoft case two decades ago.

Google, for its part, is pushing back hard. The company argues that forced divestitures are legally unwarranted and could harm internet users, suggesting instead “behavioral” remedies such as opening access to its real-time bidding systems. Google’s legal team contends that finding buyers for its ad tech assets would be challenging and disruptive.

Both sides are expected to submit detailed proposals outlining their preferred remedies in the coming days. The September trial will determine whether Google must dismantle key parts of its ad tech stack-a decision that could send shockwaves through the digital advertising ecosystem and set a precedent for future tech antitrust actions.

As Google faces mounting legal pressure in both advertising and search, the outcome of this trial could fundamentally alter the balance of power in online advertising and beyond.