Nasdaq Glitch Causes Bad Data

A technical problem with Nasdaq's trade reporting interface to the Consolidated Tape System during the afternoon and evening of last Wednesday, Jan. 18 caused firms to receive erroneous consolidated prices and volume data for stocks listed on the New York Stock Exchange, American Stock Exchange and Archipelago Exchange. SIAC rejected data on 81,000 trades reported after 3:39pm Wednesday, and in a later incident, Nasdaq sent out data with a regular sale condition