Credit reporting agency Experian reported October 1, 2015 that hackers accessed personal information of more than 15 million T-Mobile customers in a massive data breach. T-Mobile uses Experian credit bureau files to run credit checks on its customers. Experian stated that cyber thieves accessed its data base in September and stole sensitive personal information including names, addresses, social security numbers, birthdates, and other identification numbers like driver’s license, military ID, or passport information. The credit bureau company said this breach only included T-Mobile data that was housed on its server and affected consumers who applied for T-Mobile USA postpaid services between September 1, 2013 and September 16, 2015.