http://www.bloomberg.com/apps/news?pid=20601010&sid=aETiygQQ8Y3g
May 6 (Bloomberg) -- Computerized trades sent to electronic networks turned an orderly stock market decline into a rout, according to Larry Leibowitz, the chief operating officer of NYSE Euronext. Nasdaq OMX Group Inc. canceled trades in 286 securities that rose or fell 60 percent or more.
While the first half of the Dow Jones Industrial Average's 998.5-point intraday plunge probably reflected normal trading, the selloff snowballed because of orders sent to venues with no investors willing to match them, Leibowitz said in an interview on Bloomberg Television.
"If you look at the charts you can see fairly clearly where the trades came in," he said from New York. "It's that V-shaped drop where it came down and snapped right back up. You had some very high-cap stocks trading down 50 percent or large percentages in a split-instant because there really was no liquidity in electronic markets."
The selloff briefly erased more than $1 trillion in market value as the Dow average tumbled 9.2 percent, its biggest intraday percentage loss since 1987, before paring the drop. The U.S. Securities and Exchange Commission and the Commodity Futures Trading Commission are reviewing "unusual trading" that contributed to the plunge.
