Google wrapped up its defense against the Department of Justice's ad tech breakup proposal today, with testimony from rival CEOs and small business owners painting the DOJ's remedy as technically impossible and economically destructive. The testimonies could prove pivotal as the court weighs whether to force the sale of Google Ad Manager, a move that would reshape the $200 billion digital advertising market.
The curtain fell today on one of the most consequential antitrust cases in tech history, as Google concluded its defense against the Justice Department's push to break up its ad tech empire. But the real drama unfolded in the witness testimonies, where even the DOJ's own experts seemed to undercut the government's case for forcing a sale of Google Ad Manager.
James Avery, CEO of rival ad server Kevel, delivered what might have been the most damaging blow to the DOJ's position. Called as a government witness, Avery testified that Google's proposed behavioral remedies - including direct, non-preferential connections to its exchange - would "resolve the concerns in this case." For a competitor to essentially validate Google's alternative solution speaks volumes about the technical realities the court must weigh.
Even more telling was the admission from Professor Robin Lee, the DOJ's lead economist, who conceded that divestiture wouldn't be necessary if behavioral remedies were "well-crafted and enforced." That's a remarkable statement from the architect of the government's economic case for breakup.
The technical impossibility argument gained steam through testimony from Google's engineering leadership. Professor Jason Nieh called the proposed breakup a "highly complicated software engineering undertaking, with no guarantee of success," while Ad Manager's director of engineering Glenn Bernston was more blunt: "It makes no sense. One can build it, but it won't work."
But Google didn't rely solely on technical arguments. The company paraded a series of small business owners and publishers who painted the DOJ remedy as an economic disaster in waiting. Jeff Taxdahl, founder of Thread Logic, captured the sentiment perfectly: "If Google's ad tech tools are broken, it's not clear what will take their place. A fragmented system would lack Google's reach and efficiency, so we'd have to spend far more time managing multiple ad and analytics platforms."
The testimony from wikiHow CEO Elizabeth Douglas was particularly compelling, as she described her dependence on Google's advertising revenue: "I'm here today because I'm worried for my business. We require the revenue that we get from our advertising to innovate and to run our business and it scares me to think that it is going to potentially be changing." She added there's "just no SSP that I trust as much as Google, in particular with the consistency that Google pays us every month."
Perhaps most surprisingly, Pinterest CEO Bill Ready weighed in with a sophisticated argument about why breaking up Google might not solve the underlying market dynamics. "A new owner with different incentives - especially one dominant on the buy side or an AI platform optimizing for unknown objectives - could recreate the same dynamics in a new form," Ready explained to The Information. "And holding that successor accountable could take years."
The broader industry context emerged through testimony from PubMatic CEO Ravi Goel, who emphasized that ad tech "evolves at a very high pace, a relentless pace of change." This reinforces Google's core argument that static structural remedies make little sense in a rapidly evolving market where new competitors and technologies emerge constantly.
Google has consistently argued that the DOJ's case ignores the "immense competition and dynamism of the ad tech market," and today's testimonies seemed designed to illustrate exactly that point. The company's formal remedies proposal offers behavioral changes that would address the court's concerns without the massive disruption of forced divestiture.
The timing couldn't be more critical for the broader tech industry. With antitrust regulators eyeing breakups across Silicon Valley, this case sets a crucial precedent for how courts balance competition concerns against economic disruption. The testimonies suggest that even industry players who might benefit from Google's weakening are skeptical about the DOJ's remedy.
Now the focus shifts to Judge Leonie Brinkema, who must weigh whether the government has proven that only structural separation can restore competition to digital advertising. The testimonies from Google's own competitors and customers create a compelling narrative that behavioral remedies might achieve the same goals without the collateral damage.
The testimonies paint a picture of an industry torn between wanting more competition and fearing the chaos that could follow a forced breakup. Whether Judge Brinkema finds Google's behavioral remedies sufficient or orders the historic divestiture of Ad Manager, her decision will echo across every corner of digital advertising. For now, small businesses and publishers wait nervously to see if their primary revenue engine gets dismantled in the name of competition.
