The answer is: Gramm-Leach-Bliley Act
Customers' data reveal a lot of crucial information about the customers (such as their spending habit,their financial health, products that they favor , etc) . Because of this, many financial institutions often sell their data to other companies.
Gramm–Leach–Bliley Act was passed in 1999 in order to prevent this practice from ever happen again because it is considered as the violation to the privacy that protected under the constitution.
