Options Expiration (OPEX) (OPEX)

Options Expiration (OPEX) is the third Friday of every month — the day when monthly equity and index options contracts expire or must be exercised. While the basic mechanics are simple, the market dynamics around expiration day are among the most technically driven and frequently misunderstood phenomena in equities trading.

The most important mechanism is gamma exposure. As options approach expiration, their gamma (the rate of change of delta) spikes at strike prices near the money. Market makers who have sold options must continuously delta-hedge their positions, which means buying underlying shares as the price rises toward a strike and selling as it falls. This hedging activity creates self-reinforcing price dynamics — sometimes trapping prices near a "max pain" strike (the level where the most options expire worthless), and sometimes amplifying directional moves when gamma positioning is one-sided.

Quad Witching happens four times per year in the final hour of the third Friday in March, June, September, and December, when single-stock options, single-stock futures, index options, and index futures all expire simultaneously. Volume spikes to some of the highest levels of the year, price action becomes chaotic in the final 30 minutes, and the VIX typically collapses as the uncertainty resolves.

For active traders, OPEX creates two main opportunities: the volatility compression trade (selling elevated implied volatility before expiration as IV crush accelerates) and the post-OPEX gamma reset trade (once the large hedging flows clear, the market often resumes its prior trend in the following week). The Monday after OPEX has historically shown a slightly bearish bias as dealers unwind positions.