China to order reviews for firms seeking overseas listings

China said on Tuesday it will put in force new rules to increase its oversight of plans by Chinese platform firms to list on overseas stock markets in the latest move to tighten its grip on its sprawling technology sector.

The Cyberspace Administration of China (CAC) said the new rules come into effect on February 15 and require platform companies with data on more than 1 million users to undergo a security review before listing their shares overseas.

"With stock market listings there is a risk that key information infrastructure, core data, important data or a large amount of personal information could be impacted, controlled or maliciously used by foreign governments," said the CAC in a statement, reiterating a concern flagged in July when the changes were first proposed.