The Quadruple Witching is when the futures contracts of the four major financial assets expire. “The assets on which the contracts expire on that day are stock options, single stock futures, stock index futures, and stock index options. Options contracts also expire monthly. Futures contracts expire quarterly.” The third Friday of March, June, September, and December are the Quadruple Witching day.
During the Quadruple witching day, there is more volatility in the market. The last quadruple witching day was back June 18, 2021, and it was one of the historic days on the stock market, “a near-record volume of single-stock equity options was set to expire at the end of the day in the amount of $818 billion. As a result, a near-record of single stock open interest of about $3 trillion stood on June 18, 2021. Open interest refers to how many contracts are open during any given point during the day. It is an important metric for traders to watch since a large amount of open interest can move the value of the underlying stock”.