Monthly OpEx
December 2025 - SPX & SPX Index Options Historical Performance
Markets still shaky into Dec OpEx. Any bids so far this week failed towards end of day. We’ve also got the BoJ rates decision in ~3.5 hrs, expectations are for hike to 0.75%, highest since 1995.
Revisiting the OpEx paper:
Last few OpEx cycles has not seen weakness during US RTH, overnight performance improved as well.
Updated historical performance for OpEx - SPX Options:
(All option $payoffs on $200k notional position size)
1-DTE SPX Options:
Overnight:
US RTH Session:
OpEx continues to be boring… Have not seen the weakness during RTH (this year) that we’re used to seeing since 2020.
Have a great end to the week!
Realy interesting how the RTH weakness pattern has basically disappeared this year compared to post-2020 behavior. The overnight drift staying strong while intraday reversals fade suggests gamma positioning might've shifted, or maybe dealers are just managing flow diferently now. I traded around OpEx a ton in 2021-2022 and that intraday fade was super reliable, but this year it's been way more random which forced me to adjust.