However, the deal has raised concerns over how much consumer information Google has access to, and the lack of transparency and consumer information provided regarding the partnership.
According to three anonymous people who worked directly on the deal, Google and Mastercard negotiated the contract over the span of about four years.
LAWYER CHRISTINE BANNAN at the advocacy group Electronic Privacy Information Centre.
For Google, this is just another step in bridging the gap between online ads and offline sales.
Google and Mastercard reportedly have a deal that allows the search giant to link online searches to in-store purchases.
This only happens if you were logged into a Google account when you clicked the ad and only if you purchase the product offline within 30 days of clicking the ad, Bloomberg says.
However, a Google statement to Bloomberg on the advertising tool says: "Before we launched this beta product a year ago, we built a new, double-blind encryption technology that prevents both Google and our partners from viewing our respective users' personally identifiable information". Both companies, however, insisted that they do not study the activity of individual consumers and provide their customers with aggregated depersonalized data. The company also said folks can opt-out by toggling off their Web and App Activity. A report from Bloomberg reveals that this was all made possible because of the deal between Google and Mastercard in the US- one that raises serious privacy questions.
Both Google and Mastercard declined to give statements specifically related to this previously-unknown contract.
Eisen also said the information includes sales volumes and the average size of the purchase. But he said Mastercard shares transaction trends with merchants and their service providers to help them measure "the effectiveness of their advertising campaigns".
"We do not provide insights that track, serve up ads to, or even measure ad effectiveness relating to, individual consumers", the company the.
In May past year, Google quietly launched a tool called "store sales measurement" that could help it determine whether an online ad led directly to real-world purchases.
And yet, what if you see an online ad for a TV and then you buy a TV in store?
"We do not have access to any personal information from our partners" credit and debit cards, nor do we share any personal information with our partners'.