Google, Mastercard allegedly had an ad-vantageous tracking deal

Google has just recently taken on some heat about how it was handling, or rather misrepresenting, its location tracking options. "No" doesn't always mean "no", as far as the turning location tracking off. Privacy advocates, however, may have something bigger to worry about. Because according to sources familiar with the matter, Google and Mastercard inked a deal that could link online ads with what people buy in stores, allowing Google to offer advertisers deeper insight into how effective their digital ads really are.

Last year, Google announced a new service called "Store Sales Measurement". It gave merchants bulk and anonymized data that showed the percentage of shoppers who clicked online ads and later bought an item in a physical store, two activities that are hard to link without Google's tool. Naturally, Google isn't spilling the exact details of how that data is accumulated. Bloomberg's report, however, does.

According to the site's sources, Google paid Mastercard for credit card transaction data. In return, Google agreed to share ad revenue with one of the two largest credit card companies in the world. Google denies any revenue sharing with any of its partners. Mastercard only commented that it shared transaction trends with merchants and service providers, never any personally identifiable customer data.

Google does ensure its users that data is heavily encrypted and anonymized and that neither Google itself nor its partners are able to view any identifiable information. Like with location tracking, Google provides ways to let users opt out of its ad tracking, but even Google insiders complain that getting to those options isn't as straightforward as they should be.

Naturally, privacy advocates will go nuts over this report, especially since it involves Google as well as one of the world's largest credit card companies. But it isn't just Google either. Facebook, among others, has also been reported to be looking for ways to link ads on its platform to physical sales. It is definitely something that should be looked into, considering it's a whole new game that may not yet be covered by existing privacy regulations.