triple witching hour

Triple witching hour

The four times a year that the S&P futures contract expires at the same time as the S&P 100 index option contract and option contracts on individual stocks. It is the last trading hour on the third Friday of March, June, September, and December, when stock options, futures on stock indexes, and options on these futures expire concurrently. Massive trades in index futures, options, and underlying stock by hedge strategists and arbitrageurs cause abnormal activity (noise) and volatility.

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triple witching hour

The hour before the market closing when options and futures on stock indexes expire on the same day, thereby setting off frenzied trading in futures, options, and underlying securities. Traders and arbitrageurs unwind investment positions and produce large price movements in securities. The triple witching hour occurs on the third Fridays of March, June, September, and December. See also expiration effect.