Nasdaq reverses some stock orders after glitch hits trades

Nasdaq worked to fix a system error that impacted thousands of stock orders, leading some to be cancelled and incorrect clearing information to be submitted.

The exchange operator told market participants Wednesday it’s investigating an order-entry issue that caused inaccuracies and delays, according to people with knowledge of the matter. Nasdaq’s electronic communication channel, which processes so-called financial information exchange or “FIX” messages, was affected, the people said, asking not to be identified discussing a private matter.

The incident, starting around 2:30 p.m. New York time, involved “certain FIX/RASH order entry ports,” Nasdaq said in an emailed statement.

Nasdaq worked to fix the issue, but was unable to fully resolve it before the end of the day. A decision was then made after the close to shut down the FIX/RASH order handling system, block all new orders and cancel any open orders back to customers.

Also, incorrect clearing records were submitted, according a later statement. Nasdaq reversed trades for orders originating from the FIX/RASH system during the impacted period and resubmitted the corrected trades for the Nasdaq Stock Market. BX and PSX trades will be corrected on a T+1 timeframe, it said.

“Nasdaq is confident that this corrective action fully addresses the issue” and is ready for Thursday trading, the statement said.