States investigating the data breach at JPMorgan Chase this past summer are requesting that the bank hand over detailed information on its security practices and are looking to confirm whether the bank is sure that no sensitive account data was stolen.

The breach, which compromised up to 83 million customer records, exposing names, addresses and phone numbers, prompted more than a dozen states to open up an investigation into the stolen information, according to Reuters.

The states sent a letter on January 8 to JPMorgan's chief privacy officer Zoe Strickland asking whether the company's investigation had found any information that might prove that sensitive data, such as account numbers, Social Security numbers and passwords, had been stolen, too.

They also asked about the bank's knowledge of any fraud related to the attack and the steps it's taken for further protection.