Hong Kong ( CNN ) -- Beijing has clamped down on information once publicly available on listed and state-owned companies , hurting the effort of Western investors and companies to gauge whether to invest in -- or short-sell -- Chinese firms . First reported by the International Financial Law Review , the State Administration of Industry and Commerce now requires company permission before accessing records such as financial reports and shareholder information . Companies that sell credit reports -- which give companies a quick read on the background of the firm they are considering doing business with -- have been hindered , said Peter Humphrey , managing director of ChinaWhys , an international business risk advisory firm in Beijing . `` They are restricted now . They can not include personal identity information about individual shareholders or financial data from the last three years , '' he said . `` There is a major impact as many companies consume thousands of these reports every year , and that kind of information is no longer there , and it is not possible to get a reliable credit rating on this or that business partner without knowing how it 's performing financially and who owns it . '' Many believe the move may be in part a backlash against hedge funds like Muddy Waters Research , which prominently took down Chinese timber company Sino-Forest . The hedge fund has led similar short-selling crusade against other North American-listed Chinese firms such as including Focus Media , Rino International , China MediaExpress and Duoyuan Global Water , as CNNMoney reported . All were delisted after Muddy Waters ' withering reports , with the exception of Focus Media . But the information clampdown also comes at a sensitive time for Chinese leadership as it readies for its once-a-decade transfer of leadership at the top as President Hu Jintao and Premier Wen Jiabao , who are both in their final year of office . Also in the backdrop is the public rise and fall of Bo Xilai , a rising star who was dismissed as Communist Party chief of Chongqing , the biggest metropolis in China . His right-hand man and former top cop Wang Lijun spectacularly sought refuge in an American consulate apparently fearing for his life and allegedly holding incriminating information on his old boss . His wife , Gu Kailai , is also being investigated on suspicion of murdering British businessman Neil Heywood in a `` conflict over economic interests , '' according to state media . Subsequent reports suggest Bo 's family was worth millions of dollars through business dealings and powerful political connections . Difficulties getting access to information on companies `` began at the beginning of this year , and it became a lot worse after the Bo Xilai scandal , '' said Humphrey , who is founding president of the Association of Certified Fraud Examiners in Mainland China . `` The people offering due diligence services to multi-nationals considering relationships with Chinese companies are finding certain information to complete the picture is now missing when they are assessing a company for investment purposes , '' he said . `` This is a handicap to people investing in China right now . It is linked to the political atmosphere of this year 's leadership transition period , which has made China more tense , and the gathering of legitimate business information more sensitive . '' The move to limit public information on companies comes after the April arrest of 1,700 suspects in a widespread crackdown on the illegal selling of personal information , the Shanghai Daily reported , including an official in Baoding who sold large amounts registered company information . Dun & Bradstreet Corp. , which provides commercial information on businesses for credit checks , suspended its Shanghai-based market research company , Shanghai Roadway D & B Services Co. , earlier this year after allegations after a Chinese report it illegally collected information on 150 million people , the Wall Street Journal reported .
It now requires company permission before accessing detailed information . Background checks on potential Chinese investments have been increased . Some say move is in response to foreign funds who are shorting Chinese companies .