SEC approves new stock-by-stock circuit breaker rules

The move comes in response to the May 6 "flash crash" when the market dropped nearly 1,000 points before making a slight recovery. SEC and Commodity Futures Trading Commission officials are still sorting through billions of trades in search of an explanation of what happened. 

The SEC also is considering recalibrating market-wide circuit breakers that already are in place but weren't triggered during the May crash. 

The SEC recently approved a consolidated audit trail to help in investigations of unusual market fluctuations. 

The next step in market regulation is to deter or stop "stub" quotes, which aren't intended to indicate actual trading interest. 

The SEC also will consider ways to address the risks of market orders and their potential to contribute to sudden prices moves. 

Regulatory officials also will look at the effects of other trading protocols, including the use of trading pauses and self-help rules. 

Lastly, regulatory officials will work to improve the process for breaking erroneous trades by "assuring speed and consistency across the markets."