Google’s antitrust loss could reshape ad tech—how industry leaders are responding

April 17th, 2025

As seen on AdAge

Google’s latest antitrust blow sparked celebration among ad tech critics, who saw the ruling as a chance to reshape open web advertising. On Thursday, the tech giant lost part of its second antitrust case, this one having to do with its control of online ad markets, and the response from sectors of the ad community was part relief, since it seemed to corroborate what they have been saying for years—that Google has operated with impunity in programmatic advertising.

Though there is more to come in the case with appeals, ad tech leaders sensed a possible shift in how Big Tech handles its power, and that it could ripple through advertising.

The ruling, in a case argued by the U.S. Department of Justice last year, found that Google operates a monopoly through Google Ad Manager, its ad server and ad exchange used by 90% of online publishers. Judge Leonie Brinkema did offer some satisfaction to Google, deciding that the DOJ didn’t prove Google wielded monopolistic power over the advertising side of the equation, just the publishing side.

“This is a potential watershed moment in our industry,” Rajeev Goel, CEO of sell-side platform PubMatic, who testified in the case, told Ad Age after the ruling. “There’s great upside here for publishers, for advertisers and also for, ultimately, the consumers of information, who will benefit from when publishers have more control over their monetization strategies and advertisers have a more open ecosystem.”

Of course, Google intends to appeal, and that process is typically lengthy. However, Goel expected the shift in perceptions around digital ad markets could lead to immediate adjustments.

“Publishers and buyers are not going to sit around and wait,” he said.

Ad Age’s key takeaways from Google’s ad tech trial

As many ad tech players and publishers have argued for years, Brinkema found that Google used its vast control of advertising dollars to keep publishers grounded in Google Ad Manager, nudging them to use the ad server if they wanted access to advertising flowing through its ad exchange. Google Ad Manager is a combined ad server and exchange, created by merging DoubleClick (acquired by Google) with its AdX platform.

“This is the beginning of Big Tech oversight,” said Andrew Casale, CEO of supply-side platform Index Exchange, who also testified in the case, called by DOJ. Casale pointed to the earlier antitrust case against Google in search and the latest one now against Meta, as other examples.

“I suspect that the conduct within Google and Big Tech in general is going to take this into consideration, and we can probably expect them to operate in slightly different ways that will be more conducive to a competitive business environment,” Casale said. “The implication of a competitive market to the publisher is frankly lower fees that drives margins down for ad tech.”

Google said it would appeal the ruling and found reasons for optimism in that the judge did not include the advertising side of its business, sticking only to how Google operates on the publishing side of ad tech. The judge also said that Google’s purchase of DoubleClick in 2008 wasn’t anti-competitive.

Validation for critics

The case could still take years and go all the way to the U.S. Supreme Court through the appeals process. In the meantime, many ad tech, advertising and publishing leaders, some of whom are longtime critics of Google, found immediate vindication in the ruling and hoped it could lead to fairer digital ad markets.

“If you think about it, Google is the programmatic advertising business, they own the DSP, they own the ad server, which owns the decisioning that the SSP is tied to,” said Michael Shaughnessy, chief operating officer at ad tech firm Kargo. “They own the browser people use every day. They own YouTube and search, they’re the largest publisher on the internet.”

Last year, Shaughnessy testified in the case given his history in publishing and understanding of how Google has affected that side of the industry. “Hopefully this ruling does send a message that we need a competitive and transparent marketplace,” Shaughnessy said.

This case attracted a legion of ad tech elite as witnesses recalling Google’s behavior, mostly during the 2010s, as it amassed power on the buy and sell side of internet ad auctions. Testimony came from representatives of Magnite, Index Exchange, OpenX, PubMatic, Microsoft and others. The ad tech landscape is full of companies that must both get along with Google and compete with it. In the ruling, Brinkema summed up the history of Google’s moves, claiming that it wielded its power on the buying side of advertising to lock publishers into its ad-serving software. The history is familiar to ad tech experts who experienced it, according to Jason Fairchild, CEO of ad performance platform tvScientific, who also co-founded ad tech platform OpenX.

“As bad as it sounds in the documents, in practice on the frontlines it was far worse,” Fairchild said, adding that Google used “inside information on an auction-by-auction basis.”

Google’s position, working with publishers and advertisers while maintaining its own trove of information from search, YouTube and other properties, gives it a privileged position in internet ad auctions, and Google sets the terms of the auctions. Google has argued that its role in the internet ad auctions is akin to a credit card institution that facilitates both the buying and the selling in transactions. Google also denies it has used coercive tactics to attract publishers.

“Publishers have many options, and they choose Google because our ad tech tools are simple, affordable and effective,” said Lee-Anne Mulholland, Google’s VP of regulatory affairs, in an email statement about the company’s plans to appeal.

Unwinding the clock

The judge found that Google controls the market for open web display advertising, the banner and video ads that run online across the web. The open web and publishers have been fueled by Google’s pipeline to ads, especially ones coming from its own sources, such as AdWords.

“[Google] compelled publishers to use [DoubleClick for Publishers] not because they viewed it as a superior product,” Brinkema wrote in the ruling, citing the DOJ’s argument, “but rather due to Google’s exploitation of its control over AdX’s preeminent position in the open-web display ad exchange market.”

The next step in the case is likely to be the remedy stage, when the DOJ makes its case for what should be done to undo any monopolistic practices, and then the appeals process. Google faces another trial next week in the remedy phase of its search monopoly ruling, which came last year. That case found Google had too much power in the consumer search market and in text-based search ads.

In the ad tech case, it’s possible that Google could be forced to disentangle its ad server and ad exchange. In 2017, Google rebranded the merged DoubleClick for Publishers and AdX into Google Ad Manager.

“Google’s rebranding DFP and AdX under a unified name, Google Ad Manager, cannot overcome these ‘market realities,’” Brinkema wrote.

Ad tech watchers and publishing advocates said they are hoping for a realignment in the markets.

“The real question now is what comes next, does Google spin out its ad exchange, do parts of Ad Manager get sold off, or shut down?” said Ben Kartzman, president and chief operating officer of data ad tech firm Attain. “The implications are massive for advertisers and publishers, especially if we see a true separation of buying and selling sides … we could finally see an open market emerge.”