Google Faces Privacy Claims Over Bidding Data for Digital Ads

Alphabet Inc.'s Google faces a potential class action in California federal court from consumers who claim that its system for delivering digital ads breaks privacy promises and reveals personal information about users without their knowledge or consent.

In a complaint filed Friday in the U.S. District Court for the Northern District of California, consumers took aim at the tech giant’s real-time bidding system, in which data collected on Google users is provided to participants in an auction for ad placement. The winning bidder gets to place an ad, while other bidders can still see the user data, even if they ...