Stocks close lower after 3-hour outage snarls trading

The glitch affected all listed stocks, though trading on USA equities continued through other platforms. The exchange said on its official Twitter feed that the issue was internal and not due to a breach of its systems. Without a hint or warning, the Dow Jones Industrial Average suddenly experienced its lowest ever intraday point loss, but quickly recovered the losses in minutes.

By the end of the day, the Standard & Poor’s 500 index fell 34.66 points, or 1.7 percent, to close at 2,046.68.

The New York Stock Exchange halted all trading midway through its Wednesday session.

Such outages are extremely rare in USA markets – but the halt brings up memories of the August 2013 “Flash Freeze”, when trading on the Nasdaq was shut down for hours.

The computer glitch grounded many United flights around the USA for almost two hours on Wednesday morning, snarling the airline’s schedule around the country and creating long lines at airports.

“It is the most significant outage since Nasdaq’s blackout [in 2013]”, Eric Scott Hunsader, a market structure expert and CEO of data company Nanex, said. “We know less about The Wall Street Journal at this point, except that their system is back up again, as is the United Airline system”.

The White House said it was monitoring the situation, along with the Treasury Department.

Technical breakdowns have become a fact of life in United States equity markets, where everything from the routing of orders to the matching of trades is done by computers. “We can only hope”, said the 11:45 p.m. tweet. The trading halt is ongoing and has so far lasted about an hour Wednesday. Angel sat on the board of exchange company Direct Edge before it was acquired by a larger rival past year.

“This is basically the good thing about electronic trading quite frankly – the customer doesn’t have to rely on any one venue”, says Ted Weisberg, president of Seaport Securities, who has been working at the NYSE for several decades.

The White House also said that there are no signs of malicious intent and spokesman Josh Earnest said President Barack Obama has been briefed on both the NYSE and United issues. The problems would likely affect a “subset” of stocks, the exchange said.

The NYSE, like all American exchanges, was already under strict orders from the Securities and Exchange Commission, America’s main market regulator, to improve its technology to ensure glitches are avoided.

But the Federal Bureau of Investigation said that issue was probably caused by a surge in readers looking for information about the NYSE breakdown. Other exchanges were trading normally.

Trading was dramatically suspending for thousands of Wall Street stocks on Wednesday with technical reasons being cited as the cause.