(Bloomberg) -- China plans to tighten scrutiny of domestic firms’ overseas share sales and ban those whose listing could pose a national security threat. All Chinese companies seeking initial public offerings and additional share sales abroad would have to register with the China Securities Regulatory Commission, according to a consultation paper the regulator released late Friday. Under the proposals, firms whose overseas listings could threaten national security are barred from share sales, and companies whose activities raise cybersecurity concerns would go through security reviews. The changes would be the latest step by the government of President Xi Jinping to crack...