Quadruple Witching

Quadruple witching refers to a date on which stock index futures, stock index options, stock options, and single stock futures expire simultaneously. While stock options contracts and index options expire on the third Friday of every month, all four asset classes expire simultaneously on the third Friday of March, June, September, and December. Quadruple witching is similar to the triple witching dates, when three out of the four markets expire at the same time, or double witching when two markets out of the four markets expire at the same time. While it may result in increased volume and arbitrage opportunities, quadruple witching does not necessarily translate to increased volatility in the markets. Quadruple witching days witness heavy trading volume, in part, due to the offsetting of existing futures and options contracts that are profitable. (Investopedia)

https://www.investopedia.com/terms/q/quadruplewitching.asp

(Related webinar: Quadruple witching special - https://truetrader.net/topic/03-19-2021-quadruple-witching-special/