A technical glitch saw Nasdaq-listed stock prices and index levels freeze for around 15 minutes yesterday.
In an alert to traders at 13:42, picked up by Reuters, the exchange said it was looking into an issue involving its Universal Trading Platform's centralised securities information processor (SIP) data feeds.
Nasdaq-listed stocks continued to trade on some exchanges but brokers reported anomalies in some prices of some securities and reporting delays of trades to the consolidated tape, says the Wall Street Journal.
Fellow operator Direct Edge responded by briefly halting trading in all Nasdaq order books.
On Wednesday the London Stock Exchange suffered its own glitch which delayed the release of company announcements on its Regulatory News Service by around 90 minutes.