NYSE suspends trading in all securities due to a technical issue

The New York Stock Exchange suspended trading in all securities on its platform on Wednesday for what it called an internal technical issue, and cancelled all open orders as investors shifted activity to other venues.

The exchange, a unit of Intercontinental Exchange Inc, said the halt, which occurred shortly after 11:30 am EDT, was not the result of a cyber attack. Other exchanges were trading normally.

"We will be providing further updates as soon as we can, and are doing our utmost to produce a swift resolution, communicate thoroughly and transparently, and ensure a timely and orderly market reopen," an exchange spokeswoman said.

There are 11 US stock exchanges, and NYSE-listed stocks continued to trade on other venues, such as those run by Nasdaq OMX Group and BATS Global Markets.

"This is one of the rare cases where the fragmented markets we live in actually serve a purpose," said Dave Nadig, director of exchange-traded funds at FactSet Research Systems.

"If this happened at (the London Stock Exchange), you would just be sitting staring at a blank screen."

TECHNOLOGY CONCERNS

The issues at NYSE came on the same day that computer problems led United Airlines to ground all its flights for about two hours and the home page of the Wall Street Journal's website temporarily went down.

The US Department of Homeland Security said there were no signs that the problems at NYSE and United Airlines stemmed from "malicious activity," CNN reported.

Nearly all US trading is done electronically, and the NYSE outage again raised questions about the technology at exchanges after major glitches in recent years.

A technical problem at NYSE's Arca exchange in March caused some of the most popular exchange-traded funds to be temporarily unavailable for trading. And in August 2013, trading of all Nasdaq-listed stocks was frozen for three hours, leading US Securities and Exchange Commission Chair Mary Jo White to call for a meeting of Wall Street executives to insure "continuous and orderly" functioning of the markets.

The SEC said on Wednesday that it was closely monitoring the situation at NYSE. The White House said President Barack Obama had been briefed on the matter.

The New York Stock Exchange accounted for about 13.4 per cent of all equities volume last month and 12.5 per cent Tuesday according to BATS Global Markets data.

(Additional reporting by Rodrigo Campos and Caroline Valetkevitch)

(Reuters)