Alphabet’s Google entered a critical courtroom battle on Monday, seeking to avert a forced divestiture of its ad exchange business, AdX, as the U.S. Department of Justice (DOJ) and several states pursue remedies for what a federal judge has ruled to be unlawful monopolization of online advertising technology, Reuters reported.
The case, heard before U.S. District Judge Leonie Brinkema in Alexandria, Virginia, marks the government’s latest attempt to rein in Google’s dominance in digital markets, following the DOJ’s failed effort earlier this month to compel the company to sell its Chrome browser. Online publishers and rival ad tech providers, many of whom have filed private lawsuits against Google, are watching closely given the potential industry-wide consequences.
At issue is Google’s AdX platform, where online publishers auction ad space in real time when users load websites. Google collects a fee of about 20% for these transactions. The DOJ contends that Google illegally tied AdX to its publisher ad server, thereby foreclosing rivals from competing on equal terms.
Julia Tarver Wood, an attorney with the DOJ’s antitrust division, told the court in her opening statement that requiring Google to divest AdX is the only way to restore competition. “Leaving Google with the motive and the means to recreate that tie is simply too great a risk,” Wood argued, emphasizing that less structural remedies would not address the harm caused by Google’s conduct.
Google’s defense team, led by attorney Karen Dunn, countered that the DOJ’s proposed remedy is “radical and reckless,” warning it would distort competition and hand the government unprecedented control over a key technology platform. Dunn urged Judge Brinkema to adopt a more restrained approach, similar to that of a Washington, D.C. court that recently rejected most DOJ proposals in a separate case concerning Google’s dominance in online search.
The DOJ dismissed such comparisons, arguing that unlike in the search case—where Chrome was merely a distribution channel—Google’s conduct in ad tech directly entrenched its monopoly.
The trial comes amid a broader bipartisan push in Washington to curb the market power of major technology firms. In addition to Google, ongoing antitrust cases target Meta Platforms, Amazon, and Apple.
Google maintains that the DOJ’s demands are both technically unworkable and likely to create prolonged uncertainty for advertisers and publishers. The company has instead offered policy changes intended to give publishers greater freedom to work with competing platforms. Regulators, however, insist such behavioral remedies are insufficient.
Notably, Google had previously floated the possibility of selling AdX during private negotiations with European Union antitrust officials, according to reporting last year by Reuters. Internal documents from those discussions could surface as evidence in the U.S. trial.
Judge Brinkema, who has already found Google to hold unlawful monopolies in ad tech markets, must now decide what remedies are necessary to restore competition. The outcome could reshape the future of the digital advertising industry in the United States.
