China is drafting an anti-monopoly law which may force companies such as General Electric Co., Microsoft Corp. and China Petroleum & Chemical Corp. to give up leading market shares in the world's fastest-growing economy, Bloomberg reported. Under the law, local or overseas companies with more than 50 percent of China's market share for any product will be investigated. Those using dominant market positions to set unfair prices will be fined as much as 10 percent of annual sales, according to a draft obtained by Bloomberg News. ``One percent of GE's global sales is $1.5 billion while 1 percent of GE China's sales would be $50 million. Either way, these are serious penalties,'' said Stephen Maloy, vice chairman of GE China Co. China's anti-monopoly law is modeled on U.S. and European Union antitrust legislation, though the Chinese version uses a less sophisticated method to determine market dominance, according to Anping & Partners' Managing Partner Guan Anping, who worked at China's commerce ministry before his private practice.