A landmark U.S. court ruling has found Google guilty of monopolising publisher-side advertising tools. Here’s how that could reshape the digital ad industry, impact publishers, and level the playing field for rivals.
After two years of legal sparring, a federal court has sided with the U.S. Department of Justice (DOJ) and eight states, ruling that Google illegally maintained monopoly power in the digital advertising technology market. The decision could be a watershed moment for the $600 billion global digital advertising industry.
Judge Leonie M. Brinkema concluded that Google violated antitrust law by tying together its publisher ad server (DoubleClick for Publishers or DFP) and its ad exchange (AdX), blocking competition and entrenching its dominance. However, the court rejected part of the DOJ’s complaint — specifically, that Google monopolised the advertiser-side of the open web display ad network market.
The Trial: Behind the Curtain
The trial, which ran from September to November 2024, exposed a series of internal practices that prosecutors argued distorted competition. Key revelations included:
- Secret Projects like Jedi Blue and Project Poirot, where Google manipulated ad auctions to favour its own products.
- Product Bundling, which effectively locked publishers into using Google tools by making alternatives incompatible or less effective.
- Maintaining High “Take Rates” — internal emails showed Google deliberately kept its ad exchange fees high, around 20%, despite competitive pressures.
- Blocking Header Bidding, a technology that gave publishers more control over auctions but threatened Google’s dominance.
- Testimony from Competitors, like PubMatic’s CEO, who said Google refused to integrate with its API, limiting industry interoperability.
How Google Built Its Adtech Empire
The DOJ argued Google’s grip on digital advertising was no accident. It was built through a series of strategic acquisitions, starting with DoubleClick in 2008 and followed by AdMeld in 2011. These moves gave Google a commanding presence across both sides of the ad transaction — the sell side (publishers) and the buy side (advertisers).
Former Google VP Brad Bender admitted that after acquiring DoubleClick, Google’s goal was to dominate display advertising — including blocking rival technologies like header bidding, which several publishers said increased their ad revenues by 15–20%.
Internal documents and testimony showed how AdX, Google’s ad exchange, was embedded as the default in its ecosystem, creating a near-impenetrable walled garden for publishers.
The Verdict and Google’s Response
Judge Brinkema ruled that Google’s bundling of its publisher tools violated U.S. antitrust law and that its data retention practices were “deeply irresponsible,” further tarnishing the company’s legal standing.
Google responded by pledging to appeal the decision. “We won half this case and will appeal the rest,” said Lee-Anne Mulholland, Google’s VP of Regulatory Affairs. She stressed that the court did not fault Google’s advertiser tools or its acquisitions, such as DoubleClick itself.
This lawsuit focused solely on Google’s adtech stack — not its search engine dominance, which is the subject of a separate antitrust case with potentially greater implications.
According to 2024 financials, advertising made up 75% of Google parent company Alphabet’s $350 billion in revenue. However, the Google Network division (which includes AdX and DFP) contributed less than 9%, and its Ad Manager tools represented just 1.5% of 2020 operating profit, according to court documents.
What Comes Next: Remedies and Industry Fallout
The next phase of the case will determine remedies. The court could impose:
- Structural Remedies, such as forcing Google to spin off parts of its adtech business like Google Ad Manager.
- Behavioral Remedies, like banning Google from giving its own exchange preferential treatment in auctions or requiring interoperability with competitors.
Analysts suggest that any restrictions on Google’s adtools could benefit smaller adtech players. Karan Taurani of Elara Securities said this could be a long-term win for companies like Affle, but he cautioned that few competitors currently have the infrastructure to match Google’s scale.
The Stakes for Journalism and the Open Web
The ruling could have a major impact on the journalism industry, which has long argued that Google’s dominance has siphoned away revenue needed to fund reporting. Publishers testified that Google’s fees, opaque auction practices, and data-driven targeting hurt their margins and diverted ad dollars to lower-cost, lower-quality websites.
The court’s decision also underscores a rare moment of bipartisan agreement in U.S. politics, with both the Biden and Trump administrations backing the lawsuit. It sets a strong precedent amid growing global momentum to rein in Big Tech.
A Turning Point for Digital Advertising?
For years, Google has acted as gatekeeper, broker, and auctioneer in the online ad marketplace. This ruling doesn’t dismantle that system overnight, but it could mark the beginning of a more open and competitive advertising landscape.
As the DOJ bluntly stated during closing arguments, “Google is once, twice, three times a monopolist.” Whether this case finally breaks that cycle — or simply chips away at it — will depend on how the upcoming remedy phase plays out.
Until then, the digital advertising world holds its breath. A more level playing field could mean billions in reclaimed value for advertisers, publishers, and consumers alike — and signal that tech giants can no longer operate above the law.
