Adtech company OpenX has filed an antitrust lawsuit against Google in the US, accusing the tech giant of unfairly blocking competition in the digital advertising world through anti-competitive tactics.
OpenX, which operates as a supply-side platform (SSP), says Google’s self-serving practices made it nearly impossible for other ad servers and exchanges like OpenX to compete, ultimately forcing OpenX to shut down its ad server business back in 2019.
The lawsuit, filed in the US District Court for the Eastern District of Virginia, claims that Google manipulated digital ad auctions and gave special treatment to its own services. These moves hurt OpenX’s business and even negatively affected Google’s publisher and advertiser customers.
According to the complaint, Google required publishers to use its ad server, DoubleClick for Publishers, mainly to drive revenue to Google’s own ad exchange. At the same time, it restricted access to the Google Ads platform exclusively through that exchange. Google also blocked publishers from setting minimum price floors that would encourage them to use competing ad exchanges like OpenX. Most alarmingly, OpenX alleges that Google rigged auctions by controlling the ad server level, allowing it to see competing bids and then change its own bid afterwards to win more deals.
In a blog post, OpenX CEO John Gentry called this “simply not a fair auction,” saying it gave Google an unfair advantage.
“They really rigged digital advertising auctions to the disadvantage of all their competitors. The classic example is, because they controlled the auctions at the ad server level, they modified the auctions such that they could see all the bids that came in and then decide to modify the Google bid after the fact, which allowed them to win a far larger number of transactions than any of the competitors because the auction was simply not a fair auction.”
OpenX is now seeking compensation for the damage it claims to have suffered and wants a court order to stop Google’s alleged unfair practices going forward. Although OpenX hasn’t stated how much money it wants in damages, it continues to work with Google in other business areas while pushing for a fairer digital ad ecosystem.
The case highlights growing concerns about Google’s dominance in adtech, where it controls important technology linking publishers and advertisers. OpenX’s detailed 88-page lawsuit demands a jury trial and aims to hold Google responsible for “crippling competitors at every turn” by bending the rules in its favour. OpenX says Google’s actions have hurt innovation, quality, and competition across the industry.
OpenX’s lawsuit is the latest in several antitrust cases against Google. In August 2024, the US Department of Justice won a federal ruling that said Google had an illegal monopoly in online search and advertising because it used contracts to keep its dominant position and block competitors. Google has appealed that ruling. There is a major trial scheduled for September 2025 to decide how to fix this, which could lead to big changes like breaking up parts of Google’s advertising services.
Another ruling in April 2025 found that some of Google’s adtech practices violated antitrust laws, though some claims were dismissed.
Currently, Google is still involved in major antitrust battles in both the US and Europe. The results of appeals and upcoming trials in late 2025 will be crucial in determining how much power Google can keep. Possible outcomes include breaking up parts of the company or placing restrictions on its business.
