Nasdaq Says Bad Trades Justified Corinthian Halt

Mistakenly placed sell orders routed to several different trading platforms constituted "extraordinary market activity" that justified a halt in trading of shares of Corinthian Colleges(COCO Quote), the Nasdaq Stock Market said Monday.

The sell orders caused a 12-minute, 32% swoon in the shares Friday before the Nasdaq instituted an evidently spottily honored halt at about midday, after which the shares rebounded. Shares of the secondary-education provider were recently changing hands for $57.23, up 43 cents, or 0.8%, from Friday's close and slightly below Thursday's closing price of $57.52.

At least two parties to the mishap have appealed to the Securities and Exchange Commission in the episode's wake. The Nasdaq has asked for the authority to impose unilateral halts in securities that trade on its platforms, and the Pacific Stock Exchange -- which complained the Nasdaq had no legitimate reason to halt the shares -- wants the halt probed. ...