NEW YORK, July 23 (Reuters) - NYSE Euronext has revised its back-up plan for trading if an emergency closed the New York Stock Exchange and its trading floor, with a proposal that would make it easier for broker-dealers to adjust their computer systems.
The plan would transfer trading in NYSE-listed stocks to the exchange operator's all-electronic market, Arca, and is subject to approval from the U.S. Securities and Exchange Commission. It was posted on NYSE's website late Monday.
NYSE has had a contingency plan in place since 2009, which has never been used, that would also use Arca as a backup for the NYSE. The new plan, however, would reduce the amount of coding changes that broker-dealers would need to make to their computer systems in advance of an emergency.
Last year was marked by a number of software glitches that roiled the securities industry, including the failed market debut of BATS Global Markets, the botched Facebook IPO on the Nasdaq, and a costly trading error at Knight Capital Group that led to the firm's sale.
The markets were also closed for two days in late October when Superstorm Sandy bore down on the Northeast coast, causing widespread flooding, including in Lower Manhattan and parts of New Jersey, where NYSE and many trading firms are located.
The SEC responded in March, proposing a sweeping new rule that would require entities such as exchanges, which are "essential to the smooth functioning of the U.S. securities markets," to have comprehensive technology plans and procedures in place.
During Superstorm Sandy, NYSE had discussed opening for business under its contingency plan as a purely electronic trading firm for the first time in its history. But many trading firms had not tested the backup plan, and there were major safety concerns about sending employees into Manhattan to recode systems so that orders could be properly routed to the exchange.