5-minute sidecar

From MarketsWiki
Jump to: navigation, search

Following the stock market crash of 1987, the New York Stock Exchange instituted circuit breakers to halt trading during steep market declines. One such circuit breaker, called a "side-car" was instituted during the first five minutes of trading.[1]

At the open, during the first five minutes, NYSE officials would put all program trades (defined as orders involving baskest of 15 stock or more and dollar values of $1 million or higher, on hold, as if stuck in a side-car. The rule would be instituted if the CME's S&P 500 lead-month futures contract declines 12 points from the previous day's close. The side-car rule did not apply to the last 35 minutes of trading.

When triggered, all program trading market orders entered in SuperDot for NYSE-listed component stocks of the S&P 500 were diverted to a separate blind file for five minutes. After the five-minute period, buy and sell orders were paired off and become eligible for execution. If orderly trading in a stock could not resume, trading in that stock was halted and imbalance information was publicly disseminated.[2]


  1. Can it happen again?. CNN.
  2. Oversight Hearing on Market Circuit Breakers. Senate Banking, Housing and Urban Affairs Committee, Subcommittee on Securities.