How long do wireless carriers keep your data?

Have you wondered how long your wireless carrier keeps text messages, call logs and your phone's Web surfing records? There are some answers to that, from a Justice Department document prepared for law enforcement with those details.

The information was obtained by the American Civil Liberties Union of North Carolina via a Freedom of Information Act request, and shared with Wired.com.

"The document, entitled, 'Retention Periods of Major Cellular Providers,' was produced in 2010 . to advise law enforcement agents seeking to obtain cell phone records and was uncovered by the ACLU's coordinated records request on cell phone location tracking by police," the ACLU said.

Here's a snapshot for subscribers of the four major carriers' policies, each with differing lengths of time for how long they keep data:

• Verizon: Keeps records of calls and cell towers used for a year; text message details are retained for up to one year, actual text message content between 3 to 5 days; Internet session information for up to a year, and Web sites visited for up to 90 days.
• AT&T: Stores call records for between 5 to 7 years; cell tower records since July 2008; text message details for between 5 to 7 years; text message content is not retained; Internet session information and destinations for up to 72 hours.
• Sprint: Hangs onto call records and cell tower records for between 18 and 24 months. Internet session and destination info for up to 60 days; text message details for up to 18 months, depending on the device; text message content not retained; Internet session info and destination info for up to 60 days.
• T-Mobile: Retains call record details for 5 years; cell towers used, "officially, 4-6 months, really a year or more;" text message details 5 years; text message content, not kept; Internet session and destination info is not kept.

You can check out the full chart prepared by the ACLU on its website.

The chart is just one piece of a larger effort launched recently by the ACLU to find out from local law enforcement agencies "when, why and how they are using cell phone location data to track Americans," with 35 ACLU affiliates recently filing more than 381 such requests in 32 states.

"Today, most people walk around with a tracking device in their purses or pockets — a cell phone," the ACLU said:

Location data from your cell phone can make it easy to get directions or locate the closest coffee shop. But it also makes it easy for your cell phone company to find you — whether through your phone’s built-in GPS or by noting your proximity to nearby cell towers. And that location data also says a lot about you — where you go, what you do, and who you know. All too often, the government is taking advantage of outdated privacy laws to get its hands on this valuable private information by demanding it without a warrant. The public has a right to know how and under what circumstances their location information is being accessed by the government – and that is exactly what we hope our information requests will uncover.

What do you think about the various lengths of time carriers keep customers' data? Are you surprised? Depressed? Stressed? Take our poll and let us know.

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