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 US 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 differences in how long carriers retain your data.
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