U.S. stock markets are rigged, says author Michael Lewis BY JOHN MCCRANK: March 31, 2014 (Reuters) - The U.S. stock market is rigged in favor of high-speed electronic trading firms, which use their advantages to extract billions from investors, according to Michael Lewis, author of a new book on the topic, "Flash Boys: A Wall Street Revolt." High-frequency trading (HFT) is a practice carried out by many banks and proprietary trading firms using sophisticated computer programs to send gobs of orders into the market, executing a small portion of them when opportunities arise to capitalize on price imbalances, or to make markets. HFT makes up more than half of all U.S. trading volume. The trading methods and technology that make HFT possible are all legal, and the stock exchanges HFT firms trade on are highly regulated. But Lewis said these firms are using their speed advantage to profit at the expense of other market participants to the tune of tens of billions of dollars. "They are able to identify your desire to buy shares in Microsoft and buy them in front of you and sell them back to you at a higher price," Lewis, whose book is available on Monday, said on the television program "60 Minutes" on Sunday. Wage of 3 EFTA01195880