Google Challenges DOJ’s Expert Witness in Ad Tech Divestiture Trial
Alexandria, VA, September 4, 2025 — Google has moved to exclude the testimony of the U.S. Department of Justice’s (DOJ) key expert witness, Goranka Bjedov, in the upcoming remedies phase of its ad tech antitrust trial, scheduled for September 22, 2025, in the U.S. District Court for the Eastern District of Virginia. The tech giant argues that Bjedov, a former Google engineer, lacks the specialized expertise required to testify on the feasibility of a forced divestiture of Google’s ad tech assets, a remedy the DOJ is pursuing to address Google’s monopolization of open-web digital advertising markets.
Background of the Case
In April 2025, U.S. District Judge Leonie M. Brinkema ruled that Google violated Section 2 of the Sherman Antitrust Act by illegally dominating two online advertising technology markets: the ad exchange market (via Google Ad Exchange, or AdX) and the publisher ad server market (via DoubleClick for Publishers, or DFP). The ruling followed a 15-day trial in September 2024, which exposed Google’s anticompetitive practices, including acquisitions like DoubleClick and auction manipulations that stifled competition for over 15 years.
The DOJ, joined by several states, is seeking structural remedies, including the divestiture of Google Ad Manager (comprising AdX and DFP) and behavioral changes, such as data sharing and bans on self-preferencing. Google, while planning to appeal the liability ruling, has proposed less drastic behavioral remedies, like making real-time bid data available to rival ad servers and eliminating unified pricing rules.
Google’s Objection to Bjedov
Google’s motion, filed on August 28, 2025, argues that Bjedov’s testimony is inadmissible under Federal Rule of Evidence 702, which requires expert witnesses to have relevant specialized knowledge. Google contends that Bjedov, who worked as a site reliability engineer at Google from 2003 to 2016, lacks expertise in ad tech markets or corporate divestitures. The company asserts that her experience in unrelated technical areas, such as cloud infrastructure, does not qualify her to opine on the complex economic and operational implications of breaking up Google’s ad tech stack.
“Bjedov lacks the relevant experience to provide such opinions,” Google’s filing states, emphasizing that her role at Google did not involve ad tech systems like AdX or DFP. The company argues that her testimony risks misleading the court on the feasibility of divestiture, which Google claims would disrupt its integrated infrastructure, harm publishers and advertisers, and require rebuilding critical systems.
The DOJ defends Bjedov’s qualifications, citing her technical background and familiarity with Google’s internal systems as sufficient to assess the practicality of separating AdX and DFP from Google’s ecosystem. The DOJ argues that her expertise is crucial for demonstrating that divestiture is a viable remedy to restore competition in the ad tech market, which generates approximately 80% of Google’s revenue.
The Stakes of the Remedies Trial
The remedies trial, set to begin under Judge Brinkema’s oversight, will determine how to address Google’s monopolistic practices. The DOJ’s proposed divestiture of AdX and DFP aims to dismantle Google’s control over the ad tech stack, which connects publishers and advertisers for open-web display ads. The agency also seeks measures to prevent Google from leveraging its data to favor its own products and to mandate data sharing with competitors.
Google counters that divestiture is excessive, arguing it goes beyond the court’s liability findings, which cleared its advertiser tools and acquisitions like DoubleClick of anticompetitive harm. The company’s vice president of regulatory affairs, Lee-Anne Mulholland, stated, “The DOJ’s proposals have no basis in law and would harm publishers and advertisers.” Google’s alternative remedies focus on interoperability, such as sharing bid data and phasing out auction dynamics like “first look” and “last look.”
Testimony from other witnesses, including publisher monetization expert Grant Whitmore, The Trade Desk’s CRO Jed Dederick, and Digital Content Next’s CEO Jason Kint, will also shape the trial. These witnesses, who testified during the liability phase, highlighted Google’s dominance, with examples like the Daily Mail’s estimated $350,000 monthly revenue loss if it switched from Google’s ad server.
Broader Context and Potential Outcomes
The ad tech case is one of multiple antitrust battles facing Google. In August 2024, Judge Amit Mehta ruled that Google illegally monopolized online search, rejecting divestiture of Chrome and Android but imposing data-sharing remedies. The DOJ’s aggressive pursuit of structural remedies in the ad tech case reflects a broader push to curb Big Tech’s dominance, with parallel cases against Apple, Meta, and Amazon.
Legal experts are divided on the outcome. Some, like Cornell Law School’s Erik Hovenkamp, question whether divestiture is necessary, suggesting behavioral remedies could address the DOJ’s concerns about market leverage. Others, like the American Antitrust Institute’s Kathleen Bradish, anticipate the DOJ will present compelling evidence for structural relief during the trial.
If Google succeeds in excluding Bjedov’s testimony, it could weaken the DOJ’s case for divestiture, potentially limiting remedies to behavioral changes. However, a favorable ruling for the DOJ could force Google to sell off core components of its $31.7 billion ad tech business, reshaping the digital advertising landscape.
Looking Ahead
Judge Brinkema is expected to rule on Google’s motion to exclude Bjedov’s testimony by mid-September 2025, ahead of the trial. The outcome of the remedies phase, appealable to the Fourth Circuit and potentially the Supreme Court, will have significant implications for Google’s business model and the broader ad tech industry. As the trial approaches, the debate over Bjedov’s qualifications underscores the high stakes of balancing technical expertise with legal standards in one of the most consequential antitrust cases of the decade.
For more information, contact the U.S. Department of Justice at public.affairs@usdoj.gov or Google’s press office at press@google.com.