• by Laurie Sullivan , September 19, 2025

The trial in the U.S. District Court for the Eastern District of Virginia, scheduled for Monday, will determine penalties to restore competition across online advertising.

The U.S. Department of Justice (DOJ) proposes to break up Google's ad-technology business. This follows a judge's finding that Google illegally maintained a monopoly in online advertising.

The government wants to see structural remedies like forcing Google to sell its ad server, DoubleClick for Publishers (rebranded Google Ad Manager), and ad exchange tool, AdX, to break up its monopoly. The remedies trial begins September 22, 2025.

“We disagree with the Court's initial decision and will appeal it, but the process requires that we first work out remedies,” Lee-Anne Mulholland, Google vice president of regulatory affairs, wrote in a blog post Friday. “DOJ';s proposed changes go far beyond the Court's liability decision and the law, and risk harming businesses across the country.”

Mulholland believes Google's proposal addresses the court's findings and what the DOJ’s own witnesses asked for during the liability phase, without harming its customers.

Google proposes building on Ad Manager's interoperability, allowing publishers to use third-party tools to access its advertisers' bids in real-time.

The list addresses what the DOJ's own witnesses asked for during the liabilities phase, which should make it easier for publishers to use Ad Manager with other ad-tech providers.

“DOJ's case misunderstands how digital advertising works and ignores how the landscape has dramatically evolved, with increasing competition and new entrants,” Mulholland wrote. “Getting the remedies right in this new environment will be key to addressing concerns without breaking what’s working, and we look forward to making our case in court.”

That new environment includes integrating technology such as artificial intelligence to support the entire ad creation and ad-serving process. The technology opens opportunities to startups that can improve on their ad serving capabilities.

“It seems inevitable that advancements in AI will be a significant consideration in any decision on remedies, although the direction of the impact is far from clear,” Andrew Frank, vice president distinguished analyst with Gartner, wrote in an email to MediaPost. “Both sides have made arguments for and against AI’s evolving effect on competition, so these arguments may just cancel each other out.”

Frank believes that the most consequential question the judge will need to consider is how much credence to puts on Google’s claim that spinning off AdX is technically infeasible and would cause users significant harm.

“These arguments rely on judgements about the credibility of witness testimony and technical evidence which are beyond the scope of most legal considerations.” Frank wrote.

Note:  The article was updated with comments from Andrew Frank, VP distinguished analyst with Gartner.