The U.S. Department of Justice (DOJ) has secured a significant victory in its antitrust lawsuit against Google concerning the digital advertising market. On April 17, 2025, the U.S. District Court for the Eastern District of Virginia ruled that Google unlawfully maintained monopolies in the publisher ad server and ad exchange markets. Judge Leonie Brinkema determined that Google engaged in anticompetitive practices by tying its ad server (DoubleClick for Publishers) with its ad exchange (AdX), thereby excluding competitors and harming publishers and consumers .oag.state.va.us+6Reuters+6Business Insider+6AP News+5WIRED+5Business Insider+5

The DOJ had accused Google of monopolizing three key segments: publisher ad servers, ad exchanges, and advertiser ad networks. While the court found Google liable in the first two areas, it ruled that the DOJ did not sufficiently prove Google’s monopoly in advertiser ad networks .Reuters+1Business Insider+1

In response to the ruling, Google announced plans to appeal the decision. Lee-Anne Mulholland, Google’s Vice President of Regulatory Affairs, stated, “We won half of this case and we will appeal the other half.” She emphasized that the court found Google’s advertiser tools and acquisitions, such as DoubleClick, did not harm competition .Axios+10CBS Haber+10AP News+10Reuters+7Business Insider+7CNN+7

This ruling marks the second major antitrust setback for Google in less than a year, following a 2024 decision that found the company illegally monopolized the search engine market . The DOJ is now seeking remedies that could include the divestiture of parts of Google’s ad tech business, potentially leading to significant changes in the digital advertising landscape .WIRED+5AP News+5Vikipedi+5

The case underscores the increasing scrutiny of Big Tech companies and sets a precedent for future antitrust enforcement in the digital economy