Expiry week: open interest maps before the pin stories
Why we draw open-interest maps early in expiry week, and how that changes a hedge conversation.
Pin narratives travel fast in expiry week. Useful sometimes; noisy often. Before we talk about magnets, we build a simple open-interest map for the strikes that book risk actually touches.
The map in practice
For an index hedge, that usually means the strikes near the current future, the wings the desk already owns, and any large call or put walls that formed earlier in the week. We note where open interest thickened overnight and whether fresh flow is reinforcing or opposing that wall.
What changes in the briefing
Instead of a generic “watch the pin,” the conversation becomes: here is the overhang, here is the light open interest, here is where a roll might feel crowded. Clients still decide size and timing; they leave with a clearer floor plan.
This approach sits at the centre of our Options Flow Briefing.