XBI gamma exposure by strike
From the closing options book · October 20, 2026 · updated after every close
XBI closed at 153.24 on October 20, 2026 with dealers net short $15.0M of gamma. The call wall was 155 (+1.1%), the put wall 140 (−8.6%) and the apex, the single largest gamma strike, 140.
XBI largest gamma strikes within 4% of the close
The heaviest strike on the October 20, 2026 book was 155, carrying +$5.6M of dealer gamma, +1.1% from the close.
XBI closed with dealers short gamma on 46 of the last 60 sessions. In short gamma, dealer hedging buys rallies and sells drops, which tends to extend moves; in long gamma it leans against them.
Positive (green) strikes are where dealers are long gamma and hedge against the move; negative (pink) strikes are where they are short and hedge with it. These are closing levels: where hedging was concentrated last night, not targets.
These are the October 20, 2026 closing numbers. Members see XBI's map move live all session.
Common questions
At the October 20, 2026 close, XBI's net dealer gamma exposure was −$15.0M: short gamma.
155, +1.1% from the 153.24 close on October 20, 2026.
140, −8.6% from the close on October 20, 2026.
Compare: gamma exposure by strike on other tickers
Measured from the closing options book and rebuilt after every close. Nothing on this page is live. Levels are where dealer hedging is concentrated, not targets or forecasts. Not investment advice.