CHICAGO (CN) - Lax security at credit checker Experian allowed hackers to steal the personal information of 15 million T-Mobile customers, a class claims in Federal Court.
Both Experian NA and T-Mobile are named as defendants to the federal class action Brendan Moore, of Mill Valley, Calif., filed Friday in Illinois.
The lawsuit comes just one day after Schaumberg-based Experian notified T-Mobile that an attack by hackers exposed the personal information of approximately 15 million people who applied for T-Mobile services between September 2013 and September 2015.
Experian, T-Mobile's vendor that processes its credit applications, is the world's largest credit-checking company. It holds data on millions on consumers, as the law requires credit data to be maintained for at least 25 months following their application.
Moore says the stolen data includes names, address, birthdates, Social Security numbers, and drivers' license numbers, but no banking or credit card information.
"This is not the first time data maintained by Experian has been breached. An attack on an Experian subsidiary that began before Experian purchased it in 2012 exposed the Social Security numbers of 200 million Americans," the complaint states.
"Plaintiffs have already experienced suspicious activity related to the compromised data. For example, fraudulent transactions and/or fraudulent home loan applications have already begun to appear on plaintiffs' and class members' credit reports.
"As a direct and proximate result of defendants' actions and omissions in disclosing and failing to protect plaintiffs' private personal information, plaintiffs and those similarly situated have been placed at a substantial risk of harm in the form of identity theft and have incurred and will incur actual damages in an attempt to prevent identity theft."
In an open letter to those affected by the breach, T-Mobile CEO John Legere wrote: "I am incredibly angry about this data breach and we will institute a thorough review of our relationship with Experian, but right now my top concern and first focus is assisting any and all consumers affected."
All those affected are being offered two years of credit-monitoring services from ProtectMyID.
The class seeks punitive damages for negligence, and violations of the Fair Credit Reporting Act.
It is represented by Edward Wallace with Wexler Wallace.
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