Congressman Asks SEC for More Information About 1990s Illegal Trading at NYSE

Updated from 5:54 p.m. ET

A ranking Michigan congressman on Monday asked the Securities and Exchange Commission to determine why the New York Stock Exchange took two years to turn over documents pertaining to illegal trading on the exchange floor and to probe what NYSE officials knew of the trading.

In a letter to acting SEC Chairwoman Laura Unger, U.S. Rep. John Dingell, a Democrat, asked the agency to complete a report by the end of June on the status of changes the exchange has made to remedy the trading situation.

Dingell said he has new concerns about the issue after reading a story on TheStreet.com about documents regarding the trading that the NYSE only recently turned over to the SEC. The Wall Street Journal later ran a story on the same subject. Those documents included handwritten notes from NYSE official Donald Siemer that described meetings exchange officials had about the trading in the early 1990s. The notes included the phrases: "Do not tell the SEC" and "nothing in writing." ...