Google found guilty of ad tech monopoly: What's next?
Court's decision opens path to major industry restructuring, potentially ending Google's dominance in digital advertising markets.
Four days ago, on April 17, 2025, the Eastern District of Virginia issued a landmark ruling that Google illegally monopolized key digital advertising technology markets, finding the tech giant violated both Sections 1 and 2 of the Sherman Act. This decision represents the second major antitrust defeat for Google in less than a year, following last August's ruling that it monopolized search and search text advertising markets.
Judge Leonie Brinkema's 115-page ruling determined that Google violated antitrust laws by monopolizing the publisher ad server market and the ad exchange market for open-web display advertising. The court also found Google unlawfully tied these products together, forcing publishers to use Google's ad server (DoubleClick for Publishers) if they wanted access to the unique advertising demand from Google's AdWords platform.
As the case moves toward the remedies phase, industry stakeholders are weighing in on how to address Google's monopolistic practices. Brian O'Kelley, co-founder and CEO of Scope3 and former CEO of AppNexus, shared detailed thoughts on possible remedies just four days ago.
According to O'Kelley, who founded one of the major ad exchanges that competed with Google's AdX, there are several key remedies that should be considered:
"I would rule that Google can not preference its own demand in any way on its ad server or exchange, including implicitly (for instance, by being in the same identity space or same technical infrastructure). They need to demonstrate that to independent auditors on an annual basis and provide complete transaction logs, including all bids received, to their clients upon request at no additional cost," O'Kelley stated.
The tech executive further suggested that: "GAM should not be able to share any data about their transactions, context, audience, demand footprint, etc with Google that they are not also sharing equally with all other market participants."
A third key remedy proposed by O'Kelley specifies: "AdX should not have any preferential treatment within GAM. Any features of GAM that are leveraged by AdX must be available to all other ad exchanges. Similarly, DV360 and other Google products cannot have any preferential access to [GAM]."
Structural separation vs. behavioral remedies
The court must now determine whether to implement structural remedies, such as forcing Google to divest parts of its ad tech business, or behavioral remedies that would regulate how Google operates while keeping its business intact.
Interestingly, O'Kelley expressed skepticism about forcing Google to spin off its Google Ad Manager (GAM) and AdX assets. "I don't think it makes a huge difference if they spin out the GAM/AdX assets, because you'd have to prevent them from ending up being bought by anybody with a strong demand footprint (eg, tech giants, TTD, holdcos). I think it may actually be easier to keep them in Google with strong restrictions," he noted.
O'Kelley suggested that legislated regulation might be more effective than forced divestiture: "It feels like we do need legislation here to establish regulation: the internet is now just as vital to our everyday life, and as prone to monopolies, as financial markets, electricity, and water."
This perspective stands in contrast to some other industry experts. Adam Heimlich, CEO of Chalice AI, countered O'Kelley's position, stating: "I think Athey and Kanter said structural separation is required, and they know much more about this market than me."
Implications for the digital advertising ecosystem
The court's finding that Google maintained a 91% market share in the publisher ad server market through anticompetitive practices has profound implications for the advertising industry. Google's monopolistic behavior has directly impacted how publishers monetize their content, how advertisers reach consumers, and ultimately how information flows across the internet.
For publishers who have long complained about declining ad revenue, the court's finding that Google charged "supracompetitive fees" while restricting competition offers validation. The ruling details how Google implemented features called "First Look," "Last Look," and "Unified Pricing Rules" that disadvantaged competitors and restricted publishers' abilities to diversify their revenue sources.
Google's defense that its conduct represented legitimate business decisions was explicitly rejected by the court, which found instead that the company engaged in anticompetitive behavior that harmed publishers, advertisers, and ultimately consumers of information on the open web.
What this means for marketing professionals
Marketing professionals should prepare for significant changes in the digital advertising landscape. If the court implements the types of remedies suggested by O'Kelley and others, several major shifts could occur:
- More transparent bidding processes across ad exchanges
- Equal access to ad inventory for all demand sources
- Potentially lower fees as competition increases
- Greater data sharing and interoperability requirements
- New opportunities for competing ad tech providers to gain market share
The court's finding that Google maintained its monopoly power partly by preventing publishers from effectively diversifying their revenue sources suggests that more competitive markets could lead to lower take rates across the ecosystem, potentially increasing the share of advertising dollars that actually reach publishers.
For smaller advertisers and agencies who have long relied on Google's advertising platforms, increased competition might lead to more options beyond Google Ads platform, though the court noted that Google's unique access to small and medium-sized businesses through its search advertising business has been a key source of its power in display advertising.
What happens next
The court will establish a schedule for the parties to submit positions on appropriate remedies. The Department of Justice and state attorneys general will likely push for significant structural changes to Google's business, while Google will advocate for more limited behavioral remedies.
Whatever the final remedy, the decision represents a watershed moment in the regulation of digital advertising markets. Combined with last year's ruling on search monopolization, these cases signal a fundamental shift in how antitrust laws are being applied to dominant technology platforms.
Timeline
- 2008: Google acquires DoubleClick for $3.1 billion, obtaining the dominant publisher ad server and a nascent ad exchange
- 2011: Google acquires Admeld, a yield management tool that helped publishers decide which ad networks to transact with
- 2014-2015: Header bidding emerges as publishers seek to mitigate Google's advantages in the ad tech stack
- 2017: Google implements Project Poirot to adjust bids in ways that benefit AdX over rival exchanges
- 2018: Google develops Open Bidding as an alternative to header bidding
- 2019: Google implements Unified Pricing Rules, restricting publishers' ability to set higher price floors for AdX
- January 2023: The federal government and eight states file antitrust lawsuit against Google
- April 2023: Nine additional states join the lawsuit
- September 2024: Three-week bench trial concludes
- April 17, 2025: Court issues ruling finding Google liable for monopolization
- Next phase: Court to determine appropriate remedies for Google's antitrust violations