Google antitrust lawsuit: Alphabet-owned Google must confront a proposed class action lawsuit from advertisers alleging monopolistic practices in the ad exchange market, as ruled by a US judge on Friday.

However, US District Judge Kevin Castel dismissed certain other antitrust claims, including those centered on ad-buying tools utilised by major advertisers.

Castel's ruling came amidst a review of multiple cases against Google, wherein he struck down several claims while allowing at least one significant set to proceed.

In his decision, Castel noted that advertisers "have not plausibly alleged antitrust standing in the markets for ad-buying tools used by large advertisers, but they plausibly allege antitrust standing as to injuries they purportedly suffered from anti-competitive practices in the ad-exchange market and the market for small advertisers' buying tools."

Additionally, Castel specified that Gannett, the largest US newspaper chain and publisher of USA Today, could pursue a separate case to demonstrate Google's alleged fraudulent concealment of anticompetitive technology effects. Gannett accused Google of making ad space available for auction on its ad exchange, despite directly selling some of the inventory to advertisers, thereby accruing transaction fees.

Responses from Google and Gannett to requests for comment were not immediately available.

The judge also issued rulings in numerous other cases within the nationwide litigation against Google, which faces various antitrust claims.

In January 2023, the US Justice Department initiated legal action against Google, alleging abuse of dominance in digital advertising. The government sought the divestiture of the Google Ad Manager suite, encompassing Google's ad exchange, AdX.

Google Ad Manager comprises tools facilitating the sale of advertising space on websites and an exchange matching advertisers with publishers.

Concerns have been raised by advertisers and website publishers regarding Google's lack of transparency in allocating ad revenue, particularly in disclosing the distribution between publishers and Google.

(With Reuters inputs.)