Quad witching today as well so more volitiilty Market Impact of Quadruple Witching
The simultaneous expiration of stock-index futures, options on stock-index futures, single-stock options and index options can generate significant volatility and volume. For example, the March 19, 2021, quad witching day saw the most volume in the S&P 500 all of last year. The other quad witching days also had above-average activity. (See the chart below.)
The folkloric name “witching” comes from the idea of certain times when dark, supernatural forces are active. It can metaphorically apply in markets if traders are forced to unwind large derivative positions. Such events could sometimes cause unexpected moves, although newer rules have reduced much of the previous havoc. For the most part, it now causes heavy volume.