A temporary restriction on program trading in a particular security or market, usually to reduce dramatic price movements. Also known as a collar or circuit breaker.




Taobiz explains Trading Curb
When the "curbs are in" at the NYSE, it means that certain types of trading are restricted to prevent volatility. Depending on the situation, this can mean that either all trading is halted or that certain sales can be executed only on an uptick. This kind of rule was implemented after the crash of 1987 (Black Monday), as program trading was thought to be a primary cause of the drop.