Google Restricts Data-Sharing for Ads Under Privacy Pressure

Google said it would make changes to its advertising technology to better protect people’s privacy following scrutiny by European Union watchdogs.

Starting in February, Google will no longer divulge information to participants in its ad auction about the type of content on a website or page where an ad could appear, the Alphabet Inc. company said in a blog post Thursday.

This type of targeting is a major reason why Google was able to absorb the bulk of online ads bought and sold with machines, so-called programmatic advertising. Google doesn’t share its sales from web display ads, but frequently cites...