NYSE blames software update for three-hour trading halt

NYSE blames software update for three-hour trading halt
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The New York Stock Exchange said Thursday that a software update was to blame for the “technical issue” that shut down trading for more than three hours on Wednesday.

“On Tuesday evening, the NYSE began the rollout of a software release in preparation for the July 11 industry test of the upcoming SIP timestamp requirement,” the exchange said in a trader alert.


“As customers began connecting after 7am on Wednesday morning, there were communication issues between customer gateways and the trading unit with the new release. It was determined that the NYSE and NYSE MKT customer gateways were not loaded with the proper configuration compatible with the new release.”

Despite making additional updates, the exchange said, more issues began to appear in the market’s systems “mid-morning.” At 11:09 a.m., NYSE issued an alert saying that it was investigating the concerns.

“At 11:32am, because NYSE and NYSE MKT were actively trading but customers were still reporting unusual system behavior, the decision was made to suspend trading on NYSE and NYSE MKT,” the statement said.

Trading would ultimately stay suspended for more than three hours, with all operations coming back online at 3:10 p.m. Other capital markets remained open throughout the day.

The outage, hours after a technical glitch shut down operations for United Airlines, sparked fears of a cyberattack on Capitol Hill despite statements from law enforcement that there was no evidence to suggest a breach.

Market shutdowns are not unheard of. In 2013, technical issues caused the Nasdaq exchange to shut down for more than three hours. At the time, the chairwomen of the Securities and Exchange Commission called for a meeting of financial industry executives to take a look at the way securities markets function.