A federal judge has ruled that Google illegally monopolized two digital ad markets, confirming long-held suspicions within the industry.
The landmark ruling in the United States v. Google LLC ad tech antitrust case has sent ripples through the digital advertising world, confirming what many in the industry have long suspected: Google’s dominance represents not just market leadership but an illegal monopoly.
US District Judge Leonie Brinkema found that Google “willfully acquired and maintained monopoly power” in the publisher ad server and ad exchange markets—technologies she described in her ruling as the “lifeblood” of the internet, enabling publishers to generate revenue from digital advertising.
For publishers and independent ad tech, the decision is both validating and unsettling.
Emry Downinghall, SVP of programmatic revenue and strategy at Unwind Media, captures the mood: “While the ruling wasn’t surprising to those who followed the case closely, it’s still a validating moment for publishers and independent ad tech. The big questions now are: How significant is the opportunity, and how long will it take for the remedies to play out?”
There is still some uncertainty ahead, as the industry waits to see what remedies the DOJ will impose on the Big G and how swiftly any proposed changes to Google’s ad tech business might reshape the ecosystem.
The Technical Details: How Did Google Build Its Monopoly?
But while the future remains unclear, the trial put Google’s past problematic practices in sharp focus.
Judge Brinkema’s findings detail the technical mechanisms behind Google’s dominance. Central to her ruling was Google’s practice of bundling its ad server (DFP, now part of Google Ad Manager) with its ad exchange (AdX), effectively forcing publishers to use both in tandem to access critical advertiser demand.
The ruling’s emphasis on this bundling arrangement points to some likely implications for Google’s ad tech stack, according to Downinghall: “It’s hard to imagine a scenario where Google is allowed to keep bundling AdX and AdSense exclusively with GAM. Without that preferential demand, GAM becomes a less differentiated product.”
Plus, Downinghall says, “what real ad server innovation looks like remains to be seen” thanks to Google’s dominant share of the market.
Google bundling its ad server with its SSP made it nearly impossible for rival ad servers to compete. And the high costs associated with switching ad servers means publishers are less inclined to seek alternatives.
The ruling also highlighted how Google’s overwhelming market share—estimated at 84%-90% for ad servers—was protected by barriers so high that even major players like Meta abandoned attempts to compete. Google maintained a steady 20% commission on ad exchange transactions, a rate the court found publishers had little choice but to accept.
Additionally, Google’s monopoly power allowed it to impose restrictive policies such as changes to its Unified Pricing Rules, which limited publishers’ ability to set higher price floors. These moves degraded publisher transparency and limited their ability to optimize yield.
The Unheard Voices of Small, Niche Publishers
But, while publishers have their gripes with Google, it’s the platform most pubs – particularly smaller ones – know best.
Jared Collett, senior director of ad operations at Major League Fishing, voices many publishers’ apprehensions about what comes next: “Like the fall of Rome, if Google is forced to break apart, there’s likely to be chaos before any real progress. The ‘standards’ we’ve relied on—really, Google’s way of doing things—will fracture as different players push their own priorities.”
Collett further points out that this upheaval will increase costs and create short-term instability, especially for niche and small publishers that rely heavily on Google’s programmatic pipes.
“When Google kept ad-serving costs down, it didn’t need to profit from that part of the business,” says Collett. “”Now, without them setting that baseline, ad serving will become much more expensive, and smaller publishers will feel it the most.”
From Headline to Business Impact
With the Google ad tech verdict official, the industry is at an inflection point. But real change won’t be coming anytime soon.
“For publishers, my advice is to stay tuned,” Downinghall says. “Until the remedies, appeals, and timelines are clear, this feels more like a headline moment than a shift with near-term business impact.”
True transformation will depend on the specific remedies the court imposes and how long it takes for these changes to filter through the market.
Judge Brinkema’s historic decision is undoubtedly a validation of publisher grievances. But any attempt to address those grievances could prove turbulent, with new costs and instability likely before publishers reap the benefits.