The Massachusetts Bankers Association said Tuesday it is filing a class action lawsuit against TJX Companies Inc. after thieves stole data from at least 45.7 million credit and debit cards used at the retailer's stores over 17 months.
The association said it will seek to recover damages in the tens of million of dollars.
The Connecticut Bankers Association, the Maine Association of Community Banks and individual banks will be co-plaintiffs, the association said.
The Massachusetts Bankers Association said it is filing the lawsuit to "protect customer privacy and data security for customer accounts."
The TJX data breach was discovered Dec. 18 and investigators have since been looking for evidence of who hacked into the store's electronic network. TJX uncovered the breach after seeing "suspicious software" on its computer systems. The theft is believed to be the biggest breach of customer records in the United States.
The association said there have been "dramatic costs" to financial institutions to protect consumers as a result. Banks had to re-issue debit cards to customers, which can cost up to $25 per card, the association said. Banks also typically cover any fraudulent charges by replacing money in customers' accounts.
"Protecting consumers is our number one priority," said Lindsey Pinkham, senior vice president of the Connecticut Bankers Association. "However, retail data breaches are getting larger and more frequent and we cannot continue to absorb the costs."
The association said the lawsuit also will seek to prove that TJX was responsible for "negligent misrepresentation," since it said it was safeguarding and disposing of cardholder data.
TJX said it could not comment on pending litigation.