Credit Cards

What you need to know:

With more purchasing being conducted online and even offline transactions moving towards cashless methods, credit card transaction data has quietly become more sought after. They are sought by brands, retailers and investment institutions alike to understand shopper tastes, budgets and purchasing trends.

This has given rise to a complex data ecosystem consisting of an ever-growing number of players that have access to and are selling your transaction data—including credit card networks, banks, merchant processors, point of sale systems, financial apps and mobile wallets. Many of these institutions will sell your data directly or to data brokers which will then in turn sell it to marketers, hedge funds and other interested parties.

Legal mandates bar financial institutions from sharing your personally identifiable information, but many companies have found a loophole by implemented sophisticated systems (known as tokenization) that erases personal details and replaces them with randomly generated pseudonyms that act like ID codes. But even when “anonymized” in this way, researchers have found to be able to use these datasets to correctly identify individuals 90% of the time with just a handful of transactional data points.

Few of these companies disclose their data sharing policies, but many companies do acknowledge making money from transaction data. Some companies are known to have have direct partnerships with data brokers and one credit card network even has an advertising arm that help marketers use their data for targeting.

Learn More:

How credit card companies track shoppers like never before

Yodlee, one of the largest financial data brokers in the U.S. and the type of information they have

Researchers were able to use “anonymized” credit card data to re-identify individuals

Letter from several US Senators to the Chairman of the FTC to investigate one financial data broker

Visa’s advertising business that provides data powered advertising solutions to brands and retailers

What to do:

Chase and American Express have online forms you can fill out that allows you to opt-out of most data sharing. To opt out with Citibank you have to call 888-214-0017; for Discover call 800-225-5202.

Through online forms, you can also opt out of the data-sharing programs with Visa and Mastercard.

In addition, consider using Apple Card, which has the best privacy measures, as it prohibits the issuing bank (Goldman Sachs) from accessing user data. Although for maximum privacy, you will still need to opt out of Mastercard data sharing programs (which is the card network behind Apple Card).