First thing, it's actually triple-witching now. There used to be a 4th contract, but now there's only 3.
3 contracts expire on this day:
Index futures (S&P, Dow) contracts
Index options (i.e. SP:SPX ) contracts
Stock options ( NASDAQ:AAPL NASDAQ:GOOG NASDAQ:NVDA etc) contracts
Single stock futures contracts. They don't exist anymore. That's...