The Justice Department has spent years attempting to break up Google’s gargantuan advertising business across two separate antitrust lawsuits: one filed in 2020 focused on Google’s dominance in search, and a second filed in 2023 that specifically targeted Google’s ad-technology business. Both cases argued that the search giant’s grip on the digital ad economy represents an illegal monopoly. Courts have largely sided with the government in both cases. In 2024, a court determined that Google’s search business, including its exceedingly lucrative search-ad operation, was an illegal monopoly, claiming that the tech giant had “exercised its monopoly power” to dominate the search industry and search ads. Last April, a second court case – this one focused specifically on Google’s ad-tech business – also came to the same conclusion.
Following the 2024 ruling, Justice Department officials suggested a variety of ways Google’s search business could be broken up, including divesting its Chrome browser and Android operating system. But in September 2025, the judge overseeing that case, Amit Mehta, rejected those divestiture requests, ruling that Google could keep both Chrome and Android. He did order the company to end exclusive default-placement deals and share certain search data with competitors (remedies that Google is currently appealing). That same pattern held this week. In a ruling handed down on Wednesday, federal judge Leonie M. Brinkema of the Eastern District of Virginia, who oversaw the ad-tech case, said that Google would be able to keep its advertising business. Instead of selling it, the search giant will instead be required to adjust its business practices to favor competitors, Brinkema said. The New York Times notes that the judge’s ruling “did not provide specifics” as to how Google should go about doing that. Brinkema’s full written ruling will remain under seal for 14 days to allow those involved to issue necessary redactions. Her finding that Google had acted illegally in maintaining its ad-tech business dates back to April of last year; this week’s decision addressed only the remedy. Unsurprisingly, Google framed the outcome as a win. Lee-Anne Mulholland, Google’s vice president for regulatory affairs, told TechCrunch: “We’re very pleased the Court rejected the DOJ’s proposal to break apart tools that help small businesses reach new customers and grow.” The online advertising ecosystem is notoriously opaque and byzantine and, for most people unfamiliar with its complexities, difficult to grasp. Much of the government’s ad-tech case against Google revolved around the company’s tactics to ensure that its search engine was the default engine in devices across the world, which in turn helped its ad business dominate as well. To do this, Google used exclusive agreements with device manufacturers, which made it the default search engine across huge swaths of the mobile phone market, the government has argued. Google also entered into revenue sharing agreements with mobile carriers – deals where carriers earned a cut of ad revenue in exchange for keeping Google as the default – that further cemented its position as the de facto search engine across phone markets.
A Multi-Year Legal Battle Against Google’s Dominance
The legal challenges brought by the U.S. Department of Justice (DOJ) against Google represent a significant and protracted effort to dismantle what the government contends is an illegal monopoly within the digital advertising landscape. This comprehensive legal offensive has unfolded across two major antitrust lawsuits, each targeting a distinct yet interconnected facet of Google’s vast advertising empire.
The first lawsuit, initiated in October 2020, zeroed in on Google’s foundational strength: its search engine and the associated advertising revenue it generates. The DOJ’s complaint alleged that Google leveraged its dominant position in search to maintain an illegal monopoly, arguing that the company engaged in anticompetitive practices to ensure its search engine remained the default choice for users, thereby controlling a massive flow of advertising dollars.
A second, more recent antitrust suit was filed in January 2023, this one specifically and exclusively targeting Google’s ad-technology business. This case delved into the intricate workings of the digital ad market, accusing Google of orchestrating a series of monopolistic practices within the ecosystem of tools that publishers and advertisers use to buy and sell online ad space. The government argued that Google’s control over various components of this ad-tech chain—from ad servers to ad exchanges—allowed it to unfairly disadvantage competitors and stifle innovation.
Court Rulings Favor Government on Monopoly Findings
Across both of these high-stakes legal battles, the judiciary has, to a significant degree, aligned with the government’s core arguments. The findings have consistently pointed towards Google’s monopolistic behavior in the digital advertising realm.
In a pivotal decision rendered in 2024, a federal court declared Google’s search business, which includes its exceptionally profitable search advertising operations, to be an illegal monopoly. The court’s ruling explicitly stated that the technology giant had "exercised its monopoly power" to solidify its command over the search industry and, by extension, the lucrative search advertising market. This judgment underscored the government’s long-held assertion that Google’s entrenched position in search was not a product of fair competition but of deliberate monopolistic strategies.
This precedent was further reinforced in April of the same year when a separate court case, specifically examining Google’s ad-technology business, reached a remarkably similar conclusion. This ruling lent further weight to the DOJ’s broader campaign against Google’s alleged monopolistic practices, suggesting a systemic issue rather than isolated incidents.
Divestiture Debates: Search Business vs. Ad-Tech
The judicial pronouncements regarding Google’s monopolistic practices have naturally led to discussions and legal actions concerning appropriate remedies. The DOJ, emboldened by these rulings, initially proposed significant structural changes to Google’s business, particularly in relation to its search operations.
Following the 2024 ruling on Google’s search business, Justice Department officials put forth a range of potential remedies aimed at breaking up the company’s dominance. These proposals included the divestiture of key Google assets, such as its ubiquitous Chrome web browser and its dominant Android mobile operating system. The logic behind such proposals was that these platforms serve as crucial gateways to the internet, and by controlling them, Google could further entrench its search and advertising monopolies.
However, in a significant development in September 2025, the judge overseeing the search case, Amit Mehta, ultimately rejected these sweeping divestiture requests. Judge Mehta ruled that Google would be permitted to retain ownership of both Chrome and Android. While this was a setback for the DOJ’s structural breakup ambitions for the search business, the judge did impose other crucial remedies. Google was ordered to cease its exclusive default-placement deals, which had ensured its search engine was the pre-selected option on many devices and platforms. Additionally, the company was mandated to share certain search data with competitors, a move designed to foster a more competitive search environment. Google has since appealed these imposed remedies.
Ad-Tech Ruling: Business Practice Reforms Over Breakup
This week’s development in the ad-tech case mirrored the pattern observed in the search business litigation, albeit with a different outcome regarding the proposed remedies. Federal judge Leonie M. Brinkema of the Eastern District of Virginia, who presided over the ad-tech case, issued a ruling on Wednesday that addressed the appropriate measures to rectify Google’s illegal monopolistic conduct in the advertising technology sector.
In a decision that will have significant implications for the digital advertising industry, Judge Brinkema ruled that Google would not be required to sell off its advertising business. This means that the core components of Google’s ad-tech operations will remain under the company’s control. Instead of a structural breakup, the judge has mandated that Google must fundamentally alter its business practices to create a more equitable playing field for competitors. The specifics of these required business practice adjustments were not immediately detailed in the ruling, with The New York Times noting that the judge "did not provide specifics" on how Google should implement these changes.
The full written ruling from Judge Brinkema is slated to remain under seal for a period of 14 days. This confidentiality period is intended to allow the parties involved to review the document and submit any necessary redactions, particularly those pertaining to sensitive business information. The finding that Google had acted illegally in its ad-tech business dates back to April of the previous year, with this week’s decision focusing solely on the appropriate remedies to address that illegality.
Reactions and Analysis: A Win for Google, But With Caveats
Google’s response to the ruling was swift and predictably framed as a victory. Lee-Anne Mulholland, Google’s vice president for regulatory affairs, issued a statement expressing satisfaction with the court’s decision. "We’re very pleased the Court rejected the DOJ’s proposal to break apart tools that help small businesses reach new customers and grow," Mulholland stated, emphasizing the company’s narrative that its advertising technologies are beneficial for businesses.
While Google may perceive this as a win, the mandate for significant business practice reforms signals that the company will still face substantial operational changes. The ad-tech industry is notoriously complex and often opaque, making it difficult for outsiders to fully grasp the intricate mechanisms through which online advertising operates. The DOJ’s ad-tech case, in large part, focused on how Google utilized its dominant search engine position to influence and control the ad-tech ecosystem.
The Mechanics of Google’s Ad-Tech Dominance
At the heart of the government’s ad-tech case was the argument that Google employed a series of strategic maneuvers to ensure its search engine, and consequently its advertising services, remained at the forefront of online activity. A key tactic highlighted by the DOJ involved the use of exclusive agreements with device manufacturers.
These agreements were instrumental in establishing Google Search as the default search engine across a vast majority of mobile devices globally. By securing this default placement, Google significantly curtailed the ability of competing search engines to gain traction and visibility. This default status is critically important in the online world, as many users tend to stick with the pre-selected options without actively seeking alternatives.
Furthermore, Google reportedly entered into revenue-sharing agreements with mobile carriers. Under these arrangements, carriers would receive a portion of the advertising revenue generated through Google’s services. In exchange, carriers were incentivized to maintain Google as the default search engine on the devices they distributed. These dual strategies—exclusive deals with manufacturers and revenue-sharing with carriers—collectively solidified Google’s position as the de facto search engine across the mobile phone market, creating a powerful feedback loop that benefited its advertising business.
Broader Implications for the Digital Advertising Ecosystem
The outcome of the ad-tech case, while not resulting in a breakup of Google’s advertising business, carries significant implications for the future of digital advertising. The ruling that Google engaged in illegal monopolistic practices, even if the remedy focuses on practice reforms rather than divestiture, sends a clear message to the industry.
The requirement for Google to adjust its business practices suggests that the court acknowledges the need for greater competition and fairness in the ad-tech market. The lack of specific details in the ruling regarding these reforms leaves room for considerable negotiation and potential future legal scrutiny as Google implements changes. The 14-day sealing period for the full ruling will be crucial in understanding the precise nature of these mandated adjustments.
This legal saga underscores the ongoing global scrutiny of Big Tech’s market power. While Google has successfully defended its advertising business from being dismantled, the repeated findings of monopolistic behavior in both its search and ad-tech operations highlight persistent concerns about the company’s influence. The ongoing appeals in the search case and the forthcoming implementation of new practices in the ad-tech sector mean that the legal and regulatory battles surrounding Google’s advertising empire are far from over. The ultimate impact will hinge on how effectively the mandated business practice changes foster a more competitive and transparent digital advertising environment.
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