https://www.washingtonpost.com/news/the-switch/wp/2017/07/30/googles-new-program-to-track-shoppers-sparks-a-federal-privacy-complaint/

A prominent privacy rights watchdog is asking the Federal Trade Commission to investigate a new Google advertising program that ties consumers’ online behavior to their purchases in brick-and-mortar stores.

The legal complaint from the Electronic Privacy Information Center, to be filed with the FTC on Monday, alleges that Google is newly gaining access to a trove of highly sensitive information -- the credit and debit card purchase records of the majority of U.S. consumers -- without revealing how they got the information or giving consumers meaningful ways to opt out. Moreover, the group claims that the search giant is relying on a secretive technical method to protect the data -- a method that should be audited by outsiders and is likely vulnerable to hacks or other data breaches.