Every major mobile service provider in the nation retains sensitive data on their subscribers for at least a short period of time; that much we know. But what are they tracking, and how long are they holding on to the information?
These statistics were a mystery until a U.S. Justice Department memo, dated August 2010, was obtained by the American Civil Liberties Union of North Carolina and forwarded on to Wired.com.
The document, which was acquired via a Freedom of Information Act claim, is a one-page guide for law enforcement agencies that are looking to subpoena wireless companies for the sensitive information of their customers, including text messages, pictures, IP destination information and payment histories.
The PDF, neatly broken down by service provider, indicates that subscriber information is generally held on to for longer than most of us would have thought.
In terms of text messages, Verizon has the shortest retention period of one rolling year. Sprint holds on to the list of people that you have texted for 18 months, while T-Mobile (News 
- Alert) retains that data for between two and five years, depending on the billing model. Meanwhile, AT&T keeps a log for five to seven years.
Before you quit AT&T or T-Mobile, know that Verizon (News - Alert) is the only one of the top three U.S. carriers to store the actual contents of text messages. Verizon hangs on to this info for 3-5 days.
As far as location-tracking, Verizon has the tightest privacy policy, destroying cell site data after one rolling year. T-Mobile retains this location information for one year or more, while AT&T (News - Alert) holds on to it indefinitely, at least as of July 2008.
“I don’t think there is anything on this list the government would concede requires a warrant,” Kevin Bankston, a staff attorney with the Electronic Frontier Foundation, told Wired's David Kravets. “This brings cellular retention practices out of the shadows, so we can have a rational discussion about how the law needs to be changed when it comes to the privacy of our records.”
Only time will tell if this memo will force the hands of regulators to enact a stricter mobile privacy policy. Check out the PDF for more on what information your carrier is tracking.
Beecher Tuttle is a TMCnet contributor. He has extensive experience writing and editing for print publications and online news websites. He has specialized in a variety of industries, including health care technology, politics and education. To read more of his articles, please visit his columnist page.
Edited by Rich Steeves
