MCO gamma exposure by strike

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

MCO closed at 475.35 on October 20, 2026 with dealers net long $2.5M of gamma. The call wall was 490 (+3.1%), the put wall 450 (−5.3%) and the apex, the single largest gamma strike, 490.

+$2.5M
Net gamma
490
Call wall
+3.1%
450
Put wall
−5.3%
485
Gamma flip
+2.0%

MCO largest gamma strikes within 4% of the close

Strikeshort ← dealer gamma → long
490
+$1.7M
480
−$28K
— close 475.35 —
470
−$22K
460
+$56K

The heaviest strike on the October 20, 2026 book was 490, carrying +$1.7M of dealer gamma, +3.1% from the close.

MCO 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 MCO's map move live all session.

Common questions

What is MCO's gamma exposure?

At the October 20, 2026 close, MCO's net dealer gamma exposure was +$2.5M: long gamma.

Where is MCO's call wall?

490, +3.1% from the 475.35 close on October 20, 2026.

Where is MCO's put wall?

450, −5.3% 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.