An investigation found the Hong Kong unit of Shenzhen-based Guosen had processed 10,000 third-party deposits amounting to HK$5 billion for more than 3,500 clients during a 14-month period until December 2015.

The Guosen fine surpasses the HK$6 million Ping An of China Securities (Hong Kong) had to pay in 2014.

The commission said about 100 of Guosen’s clients received third-party deposits incommensurate with their financial profiles. “Some third-party deposits were withdrawn by clients soon after receiving the funds without being used for trading; and certain third parties made numerous deposits to the accounts of Guosen’s clients and had no apparent relationships with these clients,” said the SFC.

“Despite the apparent anti-money-laundering and counterterrorist financing red flags, Guosen failed to make enquiries about such third-party deposits and did not submit suspicious transaction reports to the Joint Financial Intelligence Unit in a timely manner.”

Guosen’s Hong Kong unit was founded in 1994. Hong Kong law requires brokerages and other financial firms to report large and suspicious transactions to the Joint Financial Intelligence Unit, or face penalties that can range from a fine to a reprimand.