Triple witching hour

Triple witching hour is the last hour of the stock market trading session (3:00-4:00 P.M., New York Time) on the third Friday of every March, June, September, and December. Those days are the expiration of three kinds of securities:

• Stock index futures.
• Stock market index options.
• Stock options.

The simultaneous expirations generally increases the trading volume of options, futures and the underlying stocks, and occasionally increasesvolatility of prices of related securities.

With the introduction of

• Single stock futures expiring on the same days, triple witching has become quadruple