Options trading halt due to software upgrade - NYSE

NEW YORK (Reuters) - The trading halt across U.S. options markets on Monday was due to a bug in new software being rolled out, a unit of NYSE Euronext , which operates the system, said on Tuesday.

NYSE said the software issue - the latest in a string of recent glitches across various U.S. securities markets - which affected national best bid and offer prices put out by the Options Price Reporting Authority (OPRA), related to a coding change to make message processing more efficient.

The software was partially implemented on some of the system's lines as part of the roll out when the bug was noticed, NYSE said in a note to clients.

To correct the problem, OPRA had to temporarily revert to an earlier version of the software, which required a re-start of the system, NYSE said.

OPRA told industry participants and the U.S. Securities and Exchange Commission at around 1:15 p.m. Eastern time that it would attempt a system recovery at around 1:30 p.m. The system recovery was completed at around 1:46 p.m., NYSE said. The older version of the software was in place between 1:30 and 1:46.

There are 12 U.S. options exchanges.

The outage came after officials from U.S. exchanges met last week with Mary Jo White, chairwoman of the U.S. Securities and Exchange Commission, and pledged to put better safeguards in place to prevent technology failures.

The SEC meeting was called after a software bug caused a three-hour outage in all Nasdaq-listed stocks on August 22 when the Nasdaq-run securities information processor (SIP) malfunctioned.

On Friday, trading on two of CBOE Holdings Inc's securities exchanges was halted for more than half an hour due to the technical problems with OPRA. (Reporting by Herbert Lash and John McCrank; Editing by Kenneth Barry)