Bloomberg:

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 aren’t aware of this behind-the-scenes tracking. That’s because the companies never told the public about the arrangement.

And:

The company said people can opt out of ad tracking using Google’s “Web and App Activity” online console. Inside Google, multiple people raised objections that the service did not have a more obvious way for cardholders to opt out of the tracking, one of the people said.

Off the top of your head, any idea how to find Google’s “Web and App Activity” online console?

Start off on this page: https://myaccount.google.com.

If you’re not already logged in, you’ll need to do so. Next, make your way to the “Person info & privacy” section and just start looking around, getting a sense of the options Google offers for managing your data. At the very least, be sure to check out the “Ad settings” page. Do this for each of your Google accounts.