Two separate class-action lawsuits were filed against T-Mobile USA Inc. alleging that the carrier duped its Sidekick customers into believing that their data was completely secure.

T-Mobile is optimistic that the phone numbers, pictures and other data its Sidekick customers lost due to a Microsoft computer glitch might be recovered, but a lot of damage has already been done to the carrier?s reputation (see story). And now, these lawsuits threaten to hit T-Mobile where it really hurts?in its wallet.

?This case is brought as a putative class action in California state court on behalf of Sidekick users who stored data on T-Mobile/Microsoft servers and lost data due to a data outage on the Sidekick platform,? said Andy Lustigman, principal attorney at the Lustigman Firm, New York.

?The lawsuit contends that the users lost data despite representations that the data was being backed up,? he said.

T-Mobile USA is a cellular telecommunications provider and the United States-based subsidiary of Deutsche Telekom?s T-Mobile International AG, itself based in Bonn, Germany.

Headquartered in Bellevue, WA, T-Mobile USA is currently the fourth-largest wireless carrier in the U.S. market with 32.8 million customers as of the end of 2008.

Maureen Thompson, a T-Mobile subscriber who is a resident of Snellville, GA, filed a lawsuit in federal district court in San Jose, CA. Her daughter is a Sidekick user.

In addition to T-Mobile, the class action named Microsoft Inc. and its subsidiary, Sidekick-maker Danger Inc., as defendants.

Ms. Thompson said that she filed the complaint ?for service interruptions and personal data loss suffered by her and users of the T-Mobile Sidekick line of wireless phone devices in October 2009.?

The document goes on to say that ?on or about Oct. 1, 2009, all Sidekick users began experiencing the inability to access data and content on their devices, including but not limited to instant messages, emails, contacts in their address books and even complete loss of device functionality.

?Users also began experiencing the inability to access all data services, including but not limited to email service, instant message service, social-networking service and photo service.

?By Oct. 10, 2009, T-Mobile publicly admitted that most all [sic] personal information store on the devices, including ?contacts, calendar entries, to-do lists [and] photos? were lost and believed to be permanently irretrievable.

?Estimates indicate approximately 1 million T-Mobile Sidekick users suffered catastrophic data loss.?

Oren Rosenthal, a T-Mobile subscriber and Sidekick user, filed the other lawsuit in Washington state court.

His complaint alleges that ?"T-Mobile's advertising did not disclose that T-Mobile had no backup or other service or device to ensure that the customer's stored data could be retrieved if there was a failure.?

Both class-action lawsuits allege that T-Mobile was negligent for not properly backing up Sidekick data.

?While I do not know the specifics of the T-Mobile Sidekick user agreement or what technology was provided here, given the risk of data loss, which is an inherent risk in electronic computer systems, companies that agree to provide data support should ensure that they are utilizing redundant back-ups and clearly inform users of the limitations of such data storage,? Mr. Lustigman said.

?Moreover, any company that provides data storage should still encourage consumers to perform their own backups,? he said.

T-Mobile?s statement
While T-Mobile did not comment directly on the lawsuits, it did release a statement about the Sidekick-data-loss incident:

Dear valued T-Mobile Sidekick customers:

We are thankful for your continued patience as Microsoft/Danger continues to work on preserving platform stability and restoring all services for our Sidekick customers.

We have made significant progress this past weekend, restoring services to virtually every customer.

Microsoft/Danger has teams of experts in place who are working around-the-clock to ensure this stability is maintained.

Regarding those of you who have lost personal content, T-Mobile and Microsoft/Danger continue to do all we can to recover and return any lost information. Recent efforts indicate the prospects of recovering some lost content may now be possible.

We will continue to keep you updated on this front; we know how important this is to you.

In the event certain customers have experienced a significant and permanent loss of personal content, T-Mobile will be sending these customers a $100 customer appreciation card.

This will be in addition to the free month of data service that already went to Sidekick data customers.

This card can be used towards T-Mobile products and services, or a customer?s T-Mobile bill.

For those who fall into this category, details will be sent out in the next 14 days?there is no action needed on the part of these customers.

We however remain hopeful that for the majority of our customers, personal content can be recovered.

Sidekick customers can continue to visit T-Mobile Sidekick Forums (http://www.t-mobile.com/sidekick) on a regular basis to access the latest updates, as well as FAQs regarding this service disruption. The Forums also offers tips and suggestions for rebuilding content on your device.