Vox Media has filed an antitrust lawsuit against Google, accusing the technology giant of unlawfully monopolizing key segments of the digital advertising market and harming online publishers by restricting competition.

In a complaint filed Wednesday in Manhattan federal court, Vox Media LLC alleges that Google LLC has used its dominance in publisher ad servers and ad exchanges to control how digital advertising inventory is bought and sold, effectively squeezing publishers and rival ad tech companies out of a market valued at roughly $200 billion annually.

Vox Media, whose brands include Vox, The Verge, The Cut, and Eater, claims Google operates both the largest publisher ad server and the largest ad exchange in the open web display advertising market. According to the lawsuit, Google has leveraged that position through what Vox Media describes as a long-running anticompetitive and deceptive scheme that has distorted market outcomes for more than a decade.

The publisher alleges that Google’s control has created a severe imbalance that would not exist in a competitive marketplace.

The lawsuit is the third filed this week by a major media company, following similar actions brought by Penske Media Corp. on Monday and The Atlantic on Tuesday. All three publishers are represented by Kellogg Hansen Todd Figel & Frederick PLLC.

Vox Media relies heavily on a recent U.S. Department of Justice victory in Virginia federal court, where U.S. District Judge Leonie M. Brinkema ruled after a three-week trial that Google willfully engaged in anticompetitive conduct to acquire and maintain monopoly power in the publisher ad server and ad exchange markets. Judge Brinkema found that Google unlawfully tied its publisher ad server to its ad exchange through contractual policies and technological integration.

According to Vox Media’s complaint, the company was directly harmed as a publisher customer subject to Google’s allegedly exclusionary practices. Vox Media says it is seeking both monetary damages and injunctive relief to restore competition and protect the production of journalism relied upon by millions of readers.

The suit focuses on Google’s DoubleClick for Publishers platform, which Vox Media claims controls more than 90 percent of the publisher ad server market, as well as Google’s Ad Exchange, known as AdX, which allegedly holds between 60 percent and 70 percent of the ad exchange market.

Publisher ad servers are used by digital media companies to manage ad inventory and solicit bids for available advertising space. Those bids are typically collected through ad exchanges, which conduct real-time auctions among advertisers.

Vox Media alleges Google has unlawfully tied access to its ad exchange to the use of its publisher ad server, effectively forcing publishers to adopt DoubleClick for Publishers and eliminating competing ad server providers. The company further claims Google uses its control over ad serving to suppress competition among exchanges and depress prices paid to publishers.

The complaint also accuses Google of exploiting nonpublic information from its publisher ad server to advantage its own ad exchange, thereby skewing auctions and limiting fair competition.

According to Vox Media, Google’s conduct has reduced the value of publishers’ advertising inventory and lowered overall revenue. The publisher argues that absent Google’s alleged monopolistic practices, advertisers would have access to more high-quality ad placements, users would receive more relevant advertising, and publishers could produce more premium content.

Vox Media’s lawsuit comes as U.S. District Judge P. Kevin Castel continues to oversee a related multidistrict litigation in the Southern District of New York involving Google’s ad tech practices. Earlier this week, Judge Castel consolidated several ad tech rival lawsuits and streamlined claims brought by publishers and advertisers. He also recently granted class certification to a group of publishers in a related action.

Google rejected the allegations in a statement Wednesday, calling the claims meritless.

“Advertisers and publishers have many choices, and when they choose Google’s ad tech tools, it is because they are effective, affordable, and easy to use,” a company spokesperson said.

Counsel for Vox Media did not immediately respond to a request for comment.

Vox Media is represented by attorneys from Kellogg Hansen Todd Figel & Frederick PLLC.

The case is Vox Media LLC v. Google LLC et al., case number 1:26-cv-00325, in the U.S. District Court for the Southern District of New York.