ISRG gamma exposure by strike
From the closing options book · October 20, 2026 · updated after every close
ISRG closed at 438.00 on October 20, 2026 with dealers net long $8.1M of gamma. The call wall was 475 (+8.4%), the put wall 405 (−7.5%) and the apex, the single largest gamma strike, 475.
ISRG largest gamma strikes within 4% of the close
The heaviest strike on the October 20, 2026 book was 435, carrying +$1.5M of dealer gamma, −0.7% from the close.
ISRG closed with dealers short gamma on 21 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 ISRG's map move live all session.
Common questions
At the October 20, 2026 close, ISRG's net dealer gamma exposure was +$8.1M: long gamma.
475, +8.4% from the 438.00 close on October 20, 2026.
405, −7.5% 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.