MRK gamma exposure by strike

From the closing options book · October 20, 2026 · updated after every close

MRK closed at 148.30 on October 20, 2026 with dealers net long $16.7M of gamma. The call wall was 150 (+1.1%), the put wall 135 (−9.0%) and the apex, the single largest gamma strike, 150.

+$16.7M
Net gamma
150
Call wall
+1.1%
135
Put wall
−9.0%
149.5
Gamma flip
+0.8%

MRK largest gamma strikes within 4% of the close

Strikeshort ← dealer gamma → long
152.5
+$2.5M
150
+$4.8M
149
+$482K
— close 148.30 —
148
+$268K
147
+$3.1M
146
+$3.6M
145
+$1.1M
144
−$819K
143
−$157K

The heaviest strike on the October 20, 2026 book was 150, carrying +$4.8M of dealer gamma, +1.1% from the close.

MRK closed with dealers short gamma on 0 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 MRK's map move live all session.

Common questions

What is MRK's gamma exposure?

At the October 20, 2026 close, MRK's net dealer gamma exposure was +$16.7M: long gamma.

Where is MRK's call wall?

150, +1.1% from the 148.30 close on October 20, 2026.

Where is MRK's put wall?

135, −9.0% 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.