NEW YORK Nasdaq MarketWatch said on Monday it was cancelling some trades in 11 securities that occurred within the first minute of trading on Monday.
Some of the companies impacted by the move include Black Box Corp (BBOX.O), Haynes International Inc (HAYN.O), First of Long Island Corp (FLIC.O), SP Plus Corp (SP.O), WesBanco Inc (WSBC.O) and German American Bancorp (GABC.O).
The canceled trades had price movements of 10 percent or more from the previous session's close.
The transactions occurred during the first minute of trading, between 9:30 a.m. and 9:31 a.m. EST (1430-1431 GMT), the exchange said in an alert.
Nasdaq did not say what may have caused the error.
Several of the impacted securities had been halted in morning trading.
(Reporting by Ryan Vlastelica; Editing by Bernadette Baum)