Google’s Ad Tech Litigation Defense Grows as Publishers Pile on

Antitrust lawsuits by many of the nation’s largest publishers are piling up against Alphabet Inc.'s Google, as they look to build on a ruling in a federal case that the company illegally monopolized the online advertising technology market.

Publishers including Vox, The Atlantic, Business Insider, McClatchy Media Co., Slate, and Advance Publications in recent months sued Google in the US District Court for the Southern District of New York, which consolidated the cases.

They are pursuing unspecified damages on top of the millions of dollars sought by the other publishers—including Gannett Co., Mail Media Inc., and Emmerich Newspapers—that are already part of the multidistrict litigation that began in 2021. Any new cases included in the MDL would need to be filed by spring.

The consolidated actions claim that Google monopolized competition in online display advertising services in violation of federal antitrust law. Some individual suits also include fraud and other claims.

The private plaintiffs are piggybacking off a district court ruling last year that Google had an illegal monopoly in the ad tech market, said Robin Crauthers, an antitrust partner with McCarter & English LLP, and it wouldn’t be surprising if additional publishers sue to recoup money from lost advertising revenue.

“Now the iron is sort of hot,” Crauthers said. “We are going to see a snowball effect.”

A Google spokesperson said in a statement that the publishers’ allegations are meritless. “Advertisers and publishers have many choices and when they choose Google’s ad tech tools it’s because they are effective, affordable and easy to use,” the spokesperson said.

Kellogg Hansen, which represents some of the publishers filing new suits, declined to comment.

‘Safety in Numbers’

Publishers that were previously loath to sue a major company such as Google now feel emboldened to do so collectively, said Sam Weinstein, a professor at the Cardozo School of Law, adding that there is “safety in numbers.”

Judge Leonie Brinkema’s April 2025 ruling said Google violated antitrust law in the markets for advertising exchanges and tools used by websites to sell ad space, known as ad servers, handing a partial win to the Justice Department and a group of states suing the tech powerhouse.

The plaintiffs’ side is thinking that the case has already been proven once, so it will be easier for them to do the same, said Weinstein, a former DOJ antitrust attorney. The question for those private plaintiffs now is how much in damages they can get, he added.

Litigation risks are lower for private plaintiffs given “collateral estoppel,” a legal doctrine that prevents a party from re-litigating an issue that has already been decided in a prior action, said Matthew L. Cantor, founding partner of antitrust boutique Shinder Cantor Lerner.

“You don’t have to start from ground zero to prove your case,” Cantor said.

The MDL court in late January approved a notice plan for members of the certified class of roughly 5,000 publishers that claimed they were overcharged for ad space through Google’s AdX ad exchange.

That notice plan will be sent to class members by next month: The deadline for opting out of that class and bringing an individual suit is 45 days after the notice is first sent.

“We’ve got website publishers that have been overcharged by Google for a number of years to sell ad space on their web pages, and this is to recompense that, and together with the DOJ case, put a stop to it,” said Philip Korologos, a partner with Boies Schiller Flexner LLP and a lead attorney for the AdX class.

Injunctive Relief

The tech giant is likely more stressed about potential injunctive relief than damages, antitrust lawyers said.

If there are 10 publishers seeking $100 million and that’s tripled, “it’s some real money but it’s not going to put Google out of business,” Weinstein said. “Google is way more concerned about a divestiture here.”

The Justice Department wants Google to divest AdX, arguing it’s the best way to restore competition in the market for online display advertising. Google has argued a forced selloff would be risky and has instead proposed to integrate its technology with rivals and make behavioral changes.

Brinkema is expected to rule later this year on injunctive relief and potential restrictions on the company’s business practices. In November 2025, she raised concerns about a potential sale and the identification of an appropriate buyer.

Any injunctive relief sought by the MDL plaintiffs will likely be dictated by what Brinkema orders in the DOJ case, Weinstein said.

“For those who are hoping for a breakup of the company, I think [the DOJ case] is the case to look at,” he said.

Google is represented by Axinn, Veltrop & Harkrider LLP.

The case is In re Google Digit. Advert. Antitrust Litig., S.D.N.Y., No. 1:21-md-03010.