Wells Fargo declined to comment on the suit which was filed Friday in U.S. District Court in Utah.
The plaintiffs are seeking class-action status on behalf of up to a million people who may have been affected and damages. The suit accuses Wells Fargo of “knowing theft, engagement in a continuous pattern of fraud, [and] conspiracy to commit fraud.”
About 5,300 Wells Fargo employees were fired in connection to the allegations.
The bank said in a statement at the time that it takes responsibility "for any instances where customers may have received a product that they did not request." Bank officials have also said that they believe all affected customers have been refunded, and sought to downplay the terminations, saying that they represented only about one percent of their workforce. Total refunds, the bank said earlier this month, amounted to about $2.6 million.
A portion of the banks' unauthorized deposit accounts generated about $2 million in fees, while a chunk of the credit card accounts generated about $400,000 in fees, according to a CFPB document reviewed by ABC News.
Wells Fargo spokeswoman Aimee Worsley told ABC News previously that the bank believes it has identified and refunded all affected customers, though it encourages customers who think they may have been affected to come forward.
Since the announcement of the fines against the bank, the FBI and federal prosecutors have opened an investigation, a U.S. House of Representatives committee has said it's launching an investigation and the Senate has scheduled a hearing for tomorrow.