The data included some personally identifiable information for approximately 15 million consumers in the US, including those who applied for T-Mobile USA postpaid services or device financing from September 1, 2013 through September 16, 2015, based on Experian’s investigation to date. This incident did not impact Experian’s consumer credit database

Source: Experian Notifies Consumers In The U.S. Who May Have Been Affected By Unauthorized Acquisition Of A Client’s Data