The nation’s major mobile-phone providers are keeping a treasure trove of sensitive data on their customers, according to newly-released Justice Department internal memo that for the first time reveals the data retention policies of America’s largest telecoms. The single-page Department of Justice document, “Retention Periods of Major Cellular Service Providers,” (.pdf) is a guide for law enforcement agencies looking to get information — like customer IP addresses, call logs, text messages and web surfing habits – out of U.S. telecom companies, including AT&T, Sprint, T-Mobile and Verizon. The document, marked “Law Enforcement Use Only” and dated August 2010, illustrates there are some significant ...