Shenzhen-based AI engineer Sihan Wang recently decided to liquidate all holdings in his Futu Securities account, which he opened a year ago, citing concerns that escalating regulatory oversight could restrict his ability to manage overseas investments.“I would rather step back now than risk having my funds caught up in future restrictions,” Wang said. He is now considering shifting capital into mainland-listed gold products and mutual funds.Wang’s move reflects a broader squeeze on mainland Chinese investors seeking exposure to overseas markets through Hong Kong, as authorities on both sides of the border tighten regulatory scrutiny of cross-border capital flows.Major online brokerages are restricting trading and account access. Hong Kong-based online broker Futu Securities said on Thursday that it would suspend mainland Chinese investors from adding to positions and transferring funds into their accounts from June 12. The company had already stopped opening new accounts for mainland Chinese identity card holders.Tiger Brokers and Longbridge also announced on Tuesday and Wednesday, respectively, that mainland clients would no longer be able to open new positions or increase existing holdings via their mainland trading platforms as of June 12. Clients could still reduce positions or close their accounts, but deposits from mainland clients would be suspended.The latest notices came after Beijing’s wider campaign to curb unauthorised offshore investing, which last month saw the China Securities Regulatory Commission, the People’s Bank of China, the Ministry of Public Security, and five other agencies pledge to crack down on unlicensed investment services targeting mainland clients.In May, authorities fined Futu, Longbridge, and Tiger Brokers over US$330 million for conducting securities business in mainland China without the required licences. The firms were ordered into a two-year rectification process, which included winding down their mainland operations and gradually offboarding existing clients.