China has begun limiting access to corporate filings after short-sellers used them to highlight accounting discrepancies that led to stock plunges and regulatory investigations over domestic companies listed abroad.

"In recent months, the Industry & Commerce Administrations in many key cities and provinces around China have implemented measures restricting access to the AIC files of Chinese companies," said Nathan Bush, a Beijing-based partner at the law firm O'Melveny & Myers LLP.

Tighter rules may restrict the ability of short-sellers including Carson Block's Muddy Waters LLC to use the filings to glean detailed financial information on companies. The Communist Party, which begins a leadership transition this year, also faces slowing growth and a 33 percent drop in the Shanghai Composite Index in 2010 through 2011.