Trading in Cisco Systems Inc shares was briefly halted on Thursday after triggering a circuit breaker.
According to the Nasdaq website, trading was paused due to a move of 10 percent or more in Cisco's price in a five-minute period.
Cisco fell 1.7 percent at $23 in mid-day trading.
Thomson Reuters data showed a single trade at $26, which would have represented a more than 10 percent move. The halt started at around 10:41 a.m. EDT (14:41 GMT), and trading resumed five minutes later.
NYSE Amex, where the trade occurred, said in an e-mail that all trades will stand after it had reviewed those executed at 10:41 a.m. between $23.67 and $26.
Other shares also have been halted by circuit breakers after U.S. regulators imposed new rules in an effort to prevent another flash crash, such as the one in early May, when the Dow Jones industrial average plummeted 700 points in a matter of minutes before rebounding.
The rules, introduced in June for a six-month trial period, have been controversial, with some investors saying they interfere with trading and restrict necessary price adjustments.
Previous halts included Washington Post Co , Citigroup Inc , Genzyme Corp and Anadarko Petroleum Corp.
(Reporting by Wall Street desk; editing by Jeffrey Benkoe)