Google avoids AdX breakup in ad tech antitrust case

A federal judge rejected the U.S. Justice Department’s bid to force Google to sell its AdX advertising exchange, allowing the company to keep the business despite an earlier ruling that it illegally monopolized parts of the publisher advertising technology market.

The decision leaves Google’s antitrust liability intact but rejects the DOJ’s request for a court-ordered divestiture.

Court ordered behavioral remedies. U.S. District Judge Leonie Brinkema declined to require Google to sell AdX, the marketplace where publishers sell digital advertising inventory through real-time auctions. Instead, she adopted most of the behavioral remedies proposed by both sides.

• The DOJ and a coalition of states argued Google should be forced to divest AdX after the court found the company unlawfully tied publishers using its ad server to the exchange.

Monopoly ruling stands. The decision does not change Brinkema’s April 2025 ruling that Google illegally monopolized markets for publisher ad servers and ad exchanges. The judge previously found Google’s conduct harmed publishers, the competitive process, and consumers by locking publishers into using its advertising technology.

Google argued against divestiture. Google said a forced sale would be technically difficult, create a lengthy transition, and ultimately harm customers. The company also argued the DOJ’s proposal differed from Google’s earlier offer to sell AdX during a European Union antitrust investigation.

• Ad Manager accounted for about 4.1% of Google’s revenue and 1.5% of operating profit in 2020, according to Wedbush research based on court documents. More recent financial figures were redacted.

What they’re saying. Google shared a statement on X, attributed to Lee-Anne Mulholland, Alphabet VP Regulatory Affairs:

• “We’re very pleased the Court rejected the DOJ’s proposal to break apart tools that help small businesses reach new customers and grow.”

Why we care. The court upheld its finding that Google violated antitrust law but stopped short of ordering the breakup the DOJ sought. The ruling leaves Google’s publisher ad tech business intact while relying on behavioral remedies instead of a forced sale.