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AT&T Sued Over Data Breach of 70 Million Customers Personal Information

Cohen Milstein

April 4, 2024

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The class action filing accuses AT&T of negligence and breach of contract for failing to investigate the massive data breach for nearly three years.

ATLANTA, GA – On April 3, 2024, two plaintiffs filed a class action suit against AT&T on behalf of themselves and 70 million current and former AT&T customers after an immense data breach leaked their names, addresses, phone numbers, Social Security numbers, PINs, and dates of birth. Upon learning of the breach in August 2021 when hackers auctioned the database of 70 million customers’ personally identifiable information in an online hacking forum, AT&T denied the breach ever occurred and refused to investigate further.

“AT&T failed to protect the data of its current and former customers,” said Douglas McNamara, partner at Cohen Milstein. “If AT&T has the power to require customers to hand over information for the company’s commercial benefit, it bears responsibility for safeguarding it, at a bare minimum.

Only three years later when the contents of the database were publicly leaked on the dark web and independently verified did AT&T admit the breach occurred and began an investigation.

The lawsuit alleges AT&T was negligent in its handling of customer’s sensitive personal information, which it requires from all customers and uses for commercial benefit, by failing to adequately monitor its security measures and act in a timely manner when it discovered the breach. It also alleges AT&T breached its contract with customers based on its assertions in the company privacy notice that it would adequately safeguard users’ sensitive personal data and inform them of a data breach. The privacy notice also stated AT&T would destroy former customers’ data once they were no longer needed, yet 65.4 million customers whose data was leaked were former customers.

Plaintiffs are represented by Cohen Milstein Sellers & Toll PLLC, Barnes Law Group, Stueve Siegel Hanson LLP, and Dicello Levitt LLP.


About Cohen Milstein Sellers & Toll PLLC

Cohen Milstein Sellers & Toll PLLC, a premier U.S. plaintiffs’ law firm, with over 100 attorneys across eight offices, champions the causes of real people – workers, consumers, small business owners, investors, and whistleblowers – working to deliver corporate reforms and fair markets for the common good. For more information visit