In April 2025, a U.S. federal court issued a landmark ruling: Google was found guilty of illegally monopolising two key digital advertising technology markets, the publisher ad server Google Ad Manager (formerly DoubleClick for Publishers) and its ad exchange, Google Ad Exchange.
The ruling concluded the liability phase of the legal proceedings, which examined how Google had integrated its services in a way that blocked competitors from entering the market and restricted publishers’ freedom of choice. This is not just a legal precedent; it’s a defining moment for the entire digital advertising ecosystem. It confirms what many publishers have long experienced: a lack of alternatives and a heavy dependence on Google’s technology. Now, attention shifts to the next steps following the ruling, such as a potential breakup of platforms or the creation of new regulatory frameworks. This could mean new opportunities, uncertainty, and transitional challenges for publishers.
In this blog, we explore what kind of turning point this ruling may represent and how it could reshape publishers' role in the digital advertising ecosystem in the years to come.
Google Abused Its Power in Ad Tech – Here’s How It Happened
Google’s dominance in ad tech was not solely the result of innovation, but also structural use of power. The U.S. federal court found that Google violated Section 2 of the Sherman Antitrust Act, which prohibits acquiring or maintaining monopoly power through anticompetitive means.
The ruling shows how the company used its key tools, Google Ad Manager and Google Ad Exchange, as a tightly integrated bundle that steered publishers toward choosing Google’s ecosystem over other alternatives. This kind of bundling reduced transparency and competitiveness in the market and ensured that demand continued to flow through Google’s channels.
The court also found that Google maintained commission levels significantly higher than its competitors for years, a sign that market forces were malfunctioning. The company’s share of publisher ad servers reached 91%, and Google Ad Exchange controlled 60% of open web transactions. This wasn’t just about market leadership, but about a structure that weakened competition, restricted choice, and influenced how ad revenue was distributed across the web.
Publishers Cautious Despite Ruling – Real Change May Take Time
Although the ruling is historic and confirms what many publishers have experienced for years, the reactions have been measured. This is not due to indifference, but uncertainty.
The court’s decision highlights publishers’ dependence on a single provider, lack of alternatives, and difficulty negotiating fair terms. These experiences have been acknowledged, but solutions have not yet been found. The ruling does not change the market but initiates the potential for change. The follow-up actions, such as breaking up platforms or introducing new regulations, could take years. Most publishers cannot make sudden changes to their infrastructure without clear and safe alternatives.
Smaller and mid-sized publishers rely on the stability and reliability of Google’s services. If Google is forced to withdraw or restructure, viable replacements may not emerge immediately. As one publisher aptly put it: if Google were Rome, its fall would not happen without chaos. Many are watching closely at this stage, but are waiting to make decisions until the path forward is more straightforward.
What Happens Next? Options and Implications for the Ad Market
The ruling issued in April was not just a symbolic gesture. It triggered the remedies phase, the outcome of which could shape the future of the entire digital advertising market. The U.S. Department of Justice (DOJ) has proposed a three-step plan aimed at dismantling Google’s market dominance at its roots:
1. In the first phase, Google must provide competitors real-time access to AdX data via Prebid.
2. In the second phase, the auction logic behind Google Ad Manager would be open-sourced.
3. In the third phase, Google Ad Manager and Ad Exchange would be separated from the parent company and spun off into independent entities under court supervision.
Additionally, the DOJ proposes that Google be prohibited from operating an ad exchange for ten years. A portion of the company’s ad revenue would be allocated to a fund to support the industry’s transition and help publishers cover switching costs.
Google, in contrast, has proposed lighter, behaviour-based remedies. The company has stated it will give up its Unified Pricing Rules model, offer broader data access, and commit to not reinstating its former first-look or last-look practices. However, many see these proposals as more cosmetic than corrective. The DOJ’s position is clear: a distortion of this magnitude cannot be fixed through regulation alone; it requires structural remedies.
What if Google Loses Its Dominant Position?
The market must quickly look for alternative solutions if Google is forced to step back from its dominant position. Companies like Magnite and Mediaocean have announced their intentions to offer alternatives, but building a new infrastructure is technically and financially demanding for many publishers.
Open-sourcing the auction logic could lower the barrier to entry for new players, but rebuilding the market will take time. It’s also possible that Google will shift its focus to more closed environments. The company may concentrate its efforts on platforms like YouTube, Discover, and AI-powered products, where it retains complete control. In that case, the future of the open web will increasingly rest on the shoulders of publishers and independent tech providers.
This could create new opportunities for those willing to act. Still, there’s a risk that the current open infrastructure will weaken without a shared commitment to maintaining and developing it.
Why This Ruling Could Reshape the Future of Digital Advertising
Google has now been officially found guilty of abusing its monopoly power at the core of digital advertising technology. While the decision is historic, its impact won’t be felt overnight.
A months-long remedies phase lies ahead, during which the court will review proposals, hear expert opinions, and weigh arguments from both sides. The formal remedies trial is set to begin on September 22, 2025, and final decisions could stretch into 2026. The lengthy process may result in legal follow-ups, structural changes, and a broader market reorganisation.
This is a turning point for publishers where opportunity and uncertainty go hand in hand. The ruling could open the door to fairer competition, better contract terms, and a more open technology ecosystem, but not without the challenges of a transitional phase. Now is the time to pause and evaluate your technology strategy, bargaining position, and dependencies. Those who adapt quickly may find a competitive advantage in the disruption.