Mastercard sold Google data on cardholders' in-store credit card use

For the past year, select Google advertisers have had access to a potent new tool to track whether the ads they ran online led to a sale at a physical store in the U.S. That insight came thanks in part to a stockpile of Mastercard transactions that Google paid for. But most of the two billion Mastercard holders arent aware of this behind-the-scenes tracking. ...Google paid Mastercard millions of dollars for the data, according to two people who worked on the deal, and the companies discussed sharing a portion of the ad revenue, according to one of the people.