The deposit in question exceeded that which is guaranteed by FDIC.
And your summary was flat-out disingenuous; you presented it as the bank suing the customer, when in effect it appears to be the bank seeking a court declaration that the bank's own security measures were not at fault, as a response to the customer's claims against the bank.
And your summary was flat-out disingenuous; you presented it as the bank suing the customer, when in effect it appears to be the bank seeking a court declaration that the bank's own security measures were not at fault, as a response to the customer's claims against the bank.