Pinning is the tendency of a stock to close near a heavily traded option strike at expiry, produced by hedging flows. Ordinary pinning is a mechanical effect; deliberately trading to force it is manipulation.
manipulation techniques · updated 2026-09-08
Where does pinning come up?
This term is used in the following manipulation techniques, each explained in full on
its own page.
Options expiry pinning— Options expiry pinning is trading to hold a share price at or across an option strike at expiry, exploiting the fact that a few cents of movement decides whether large positions pay out or expire worthless.
See also
Settlement price— The settlement price is the official end-of-session price used to mark positions, calculate margin and settle expiring contracts. …
Gamma hedging— Gamma hedging is the continual adjustment of a delta hedge as the underlying price moves. In aggregate it mechanically dampens or …