** Shares of billionaire Mark Cuban-backed digital banking firm Dave DAVE.O drop 9.3% to $85.68

** The U.S. Department of Justice on Monday filed a complaint against DAVE and its CEO, Jason Wilk, for allegedly deceptive practices

** Company advertised instant cash advances of up to $500 for their consumers, but charged "hidden" fees that they do not clearly disclose - DoJ

** The company and its CEO "very rarely offer consumers anywhere near the advertised $500" and "often do not offer any cash advance at all", the watchdog says

** Many of the DoJ's claims were incorrect, Dave says, adding that it will defend itself

** However, the company is rolling out a streamlined fee structure it had unveiled earlier to remove some of the fees at the center of the regulator's concerns

** Stock has jumped more than 11-fold YTD, as of last close

(Reporting by Niket Nishant in Bengaluru)

((Niket.Nishant@thomsonreuters.com))