Power Failure Hits Nasdaq Services

The Nasdaq Stock Market said two of its trading services, the Small Order Execution System and SelectNet, were disrupted for about 45 minutes Thursday by a processor failure at its main computer site in Trumbull, Conn.

SOES and SelectNet were down between 12:03 p.m. and 1:15 p.m. EST, Nasdaq spokesman Robert Ferri said, adding that technicians have repaired the problem.

“The regular Nasdaq market was up and running all day,” Ferri said. “This did not have a sizable impact on the market.”

SOES is used for automatic execution of trades of 500 shares or fewer, and SelectNet is an institutional trading system that allows investors to display bids and offers anonymously.

Datek Securities Corp., one of the biggest users of the SOES system, estimates that the outage cost the firm and its customers about $50,000 in lost commissions and trades, said Michael McCarty, a trader at Datek.

Traders at big brokerages were less affected by the interruptions than firms such as Datek that rely heavily on SOES.