An Internet oligopoly is forming among Chinese Internet enterprises, with Baidu Inc, Tencent Hodingd, Ltd, and Alibaba Holding Group, Ltd, taking up 70 percent of the total market value of all listed Internet companies in China, the Chinese finance website Hexun reported Friday, citing a research report on Internet monopoly released by Chinalabs, a Beijing-based Internet research company, on Thursday.

The three Internet giants hold stable monopolized positions in the sectors of search engines, instant messaging and e-commerce, respectively, which poses challenges to the interests of Internet users, the prosperity of the industry and government supervisions, the report said.

Related readings:  Measures to protect IPR on the Web  E-shoppers storm the Web  Web archive makes Kennedy virtually real for new generation  Murdered protester's son takes fight to Web

In 2010, the total market value of Baidu, Alibaba (only B2B business) and Tencent reached $77.4 billion, according to Chinalabs’ calculations. As of November 2010, the market value of all China’s listed Internet enterprises reached $110.5 billion, and that of the whole industry totaled approximately $150 billion.

According to the Chinalabs report, in the third quarter of 2010, Tencent took up 76.56 percent of the market share of instant messaging, with 636.6 million active accounts. Baidu took 72.3 percent of the market shares of search engines, while Alibaba took up 54.39 percent of the the B2B business.