SPX dealer gamma positioning

Tuesday, November 18, 2025 · reconstructed from the 0DTE options tape

SPX opened at 6,639.45 and closed at 6,617.56, down 0.33% on the session (range 6,577.28–6,666.45). The close sat 79.4 points above the zero-gamma flip at 6,538.2 — dealer hedging in vol-dampening territory. Call resistance 6,630, put support 6,635. 0DTE ATM IV opened at 16.2%.

Price stayed on one side of the flip for the whole session. The tape spent 68% of the day above VWAP. The expected-hold band 6,538.5–6,716.7 contained the entire session.

Open → Close6,639.45 → 6,617.56 (-0.33%)
Session range6,577.28 – 6,666.45
VWAP at the close6,631.76
Zero-gamma flip6,538.2
Call resistance6,630
Put support6,635
Expected-hold band6,538.5 – 6,716.7
0DTE ATM IV at the open16.2%
Net-gamma percentile88
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The terminal replays the full session minute by minute: dealer gamma, vanna and charm by strike, the flip and hold levels as they moved, IV and realised vol side by side. Every historical session is free and needs no account. New to these terms? Start with what GEX is.

Measurements are model output derived from public trade and quote data; they are approximations and can be wrong. Nothing here is investment advice — see the Terms.