After having a heckuva time dealing with backlash over its recent fake accounts fiasco, Wells Fargo has another debacle on its hands: A new report says a lawyer for the bank accidentally released a whole lot of confidential information about tens of thousands of its richest clients.

According to The New York Times, a lawyer for a former Wells Fargo employee had subpoenaed the bank in connection with a defamation lawsuit against a bank worker.

Both the lawyer and his client thought they’d get a few emails and documents related to the case, but instead, received about 1.4 gigabytes of files packed full with information.

What Was In The Files, And Whose Information Was Included?

Customers’ names and Social Security numbers, financial details about their investment portfolios, and fees charged by the bank were all included in the trove of spreadsheets, the Times reports. No written confidentiality agreement was in place between the two parties.

The former employee figures he’s got the financial information for at least 50,000 individual customers — representing the details for tens of billions of dollars invested through the bank — but again, these are not your average earners. One client, for example, is a “well-known hedge fund billionaire” with at least $23 million invested through Wells Fargo.

“There are thousands of documents in here that the public should never see,” former employee said, adding that if someone else had received those files — possibly a person with bad intentions — the information could have been released to the public.

It Was An Accident

It all comes down to a mistake made by a lawyer at an outside law firm hired by the bank. After the worker and one of his lawyers notified her about the sensitive information they’d received, she said the disclosure was “inadvertent.”

“Obviously this was done in error and we would request that you return the CD asap so that it can be properly redacted,” she responded to the man and his lawyer.

The former worker intends to keep the information secure, his attorney says.

“We are continuing to evaluate his legal rights and responsibilities,” he told the Times. “Wells Fargo has not identified what specific documents it asserts were inadvertently exposed.”

The bank said in a statement that it “takes the security and privacy of our customers’ information seriously.”

“We are investigating this matter and will take the proper steps based on the outcome of our investigation,” Wells Fargo said.

What’s Next?

Under federal law, financial institutions should notify consumers if their personal information “is subject to a breach that poses a significant risk of identity theft or related harm” — which Wells Fargo may likely do in the coming days.

Things could get more complicated as some accounts listed in files have a foreign owner, making them subject to other countries’ regulations, notes the Times.

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