NYSE asks SEC to reinstate volatility curbs

NYSE Euronext asked U.S. regulators on Friday to allow it to reintroduce rules to curb excessive trading volatility after several New York Stock Exchange-listed securities recently experienced sharp unintended drops.

NYSE had a system in place to slow trading when a stock's price moved rapidly over a short period of time, but had to cancel it when the U.S. Securities and Exchange Commission introduced market-wide rules for trading halts in April.

The SEC's new system is being introduced in phases, and there are currently gaps when it is not in effect around the opening and close of the market each day.

NYSE said that reinstating its volatility curbs would "benefit investors, issuers, and market stability by offering an additional layer of protection during the periods currently not covered by" the SEC's rules.

On May 17, NYSE canceled trades in Anadarko Petroleum Corp after the company's value briefly plunged by 99 percent shortly before the market closed. And on May 23, shares of American Electric Power Inc and NextEra Energy Inc each plunged more than 50 percent in the first minute of trading, and then rebounded.

(Link to the NYSE filing: http://link.reuters.com/pyp58t)

(Reporting by John McCrank; Editing by Leslie Adler)