Shares in Futu Holdings, the Hong Kong-headquartered online financial services company known internationally for its Moomoo and Futubull platforms, plunged by nearly 28% on the Nasdaq on Friday after the company said it was facing an investigation by China’s securities regulator. Futu, whose founder and CEO is Chinese billionaire Li Hua, announced in a press release it had “received a Notice of Investigation and an Administrative Penalty Pre-Notification Letter” from the China Securities Regulatory Commission, or CSRC, and its Shenzhen bureau in connection with its operations in mainland China. The CSRC said certain Futu entities in mainland China and Hong…