http://online.wsj.com/article/SB1000...512300248.html
BUSINESS | MAY 19, 2010
'Flash Crash' Plan: a Circuit Breaker for Every Stock
By FAWN JOHNSON And KRISTINA PETERSON
Regulators on Tuesday proposed new curbs to tame volatility in individual stocks, in an initial response to the May 6 "flash crash" that caused some shares to fall to as low as one penny.
The Securities and Exchange Commission said trading would pause in certain stocks if the price moved 10% or more in a five-minute period, under a plan set to start in mid-June for a six-month pilot period.
If made permanent, the change would mark a fundamental shift in the day-to-day workings of the stock market. The speed with which the SEC responded to the May 6 mayhem—and the cooperation it won from major stock exchanges—suggest the sensitivity of regulators to Wall Street's hiccups in the wake of the financial crisis, even at the price of restricting the natural flow of trading.
The Dow Jones Industrial Average fell nearly 1,000 points in a few minutes on May 6 before recouping much of the loss. The SEC's new "circuit breakers" on individual stocks are intended to kick in if that kind of volatility happens again.
Stock-exchange executives praised the new rule. NYSE Euronext's chief operating officer, Lawrence Leibowitz, said it is a "good step toward restoring faith in the markets."
"This is meant to prevent a stock trading at $40 one minute, a penny the next, and $39 the next minute," said William O'Brien, chief executive of the electronic stock-trading platform Direct Edge.
According to the SEC, 30 S&P 500 stocks fell at least 10% in a five-minute period on May 6 and would have been subject to the proposed circuit breaker.
A report released Tuesday by staff at the SEC and the Commodity Futures Trading Commmission said regulators haven't pinpointed a single cause for the plunge but believe a sudden draining of liquidity likely played a role.
Regulators and exchanges are still struggling to adapt to an age of automated trading systems that react almost instantly to falling stock prices in ways that are hard to predict.
The report said regulators are looking closely at trading in the E-Mini S&P 500 futures contract, which may have sparked selling in the cash market.
In addition to the new curbs on individual stocks, the SEC said it is weighing whether to beef up market-wide circuit breakers currently on the books, none of which were triggered on May 6.
Such a circuit breaker is likely to be tied to moves in the Standard & Poor's 500 stock index, according to people close to the discussions.
Regulators are also reviewing the way trades can be canceled, after the exchanges decided to nullify all trades whose prices swung above or below 60% of the stock's 2:40 p.m. price on May 6.
The SEC and CFTC said they are going through more than 25 gigabytes of data to figure out what happened that day.
During the pilot program, the SEC said, it will consider whether it should ban "stub" quotes, a practice of offering pennies for valuable stocks. Such quotes are essentially placeholders but can end up being executed when market makers step out of the market and no legitimate quotes exist.