Under the planned rule, directors could apply to have their residential addresses and full identity card numbers blocked from public view, according to a document submitted to the Legislative Council.

Mining of company data has helped news organizations uncover sensitive data on business and political leaders in recent years, which has led to the publication of stories embarrassing to some members of China's elite.

Last year, Reuters traced companies belonging to Xu Ming, a key business ally of disgraced Chinese politician Bo Xilai, through his Hong Kong holding companies.

In October, the New York Times, citing corporate and regulatory records, said the family of China's outgoing Premier Wen Jiabao had amassed $2.7 billion in wealth at one point.

Bloomberg News last year relied on Hong Kong and Chinese identity card numbers revealed in corporate filings to highlight the business relationships and assets of the family of China's incoming president, Xi Jinping.

China's new leadership, which was anointed in November, has shown few signs of steering a path of political reform or allowing freer expression.

Access to the websites of Bloomberg and the New York Times has been blocked since they published the sensitive articles.

Hong Kong's Financial Services and the Treasury Bureau as well as the Companies Registry, which have proposed the restrictions, want to bring them into effect in the first quarter of 2014.

Neither organization was immediately available to comment.

In November 2011, Reuters found a residential address of a key person in the Olympus Corp accounting scandal after searching company filings in Hong Kong.

(Reporting By Grace Li; Editing by Anne Marie Roantree and Daniel Magnowski)

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