SPX dealer gamma positioning

Wednesday, February 1, 2023 · reconstructed from the 0DTE options tape

SPX opened at 4,064.75 and closed at 4,117.72, up 1.30% on the session (range 4,041.42–4,146.78). The close sat 1.2 points above the zero-gamma flip at 4,116.5 — dealer hedging in vol-dampening territory. Call resistance 4,120, put support 4,115. 0DTE ATM IV opened at 24.7%.

Price crossed the flip 8 times, first at 09:47 ET. The tape spent 45% of the day above VWAP. The session traded outside the expected-hold band 4,114.8–4,134.8 at some point.

Open → Close4,064.75 → 4,117.72 (+1.30%)
Session range4,041.42 – 4,146.78
VWAP at the close4,072.42
Zero-gamma flip4,116.5
Call resistance4,120
Put support4,115
Expected-hold band4,114.8 – 4,134.8
0DTE ATM IV at the open24.7%
Net-gamma percentile100
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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.