Net GEX (Gamma Exposure)
Options dealers sit on the other side of most trades, and they hedge to stay neutral. Net GEX measures how much hedging pressure that creates — the sum, across every strike, of each contract's open interest times its gamma times the index price, with calls adding and puts subtracting.
Net GEX = Σ ( open interest × gamma × spot ) — calls (+), puts (−)Positive net GEX — dealers are long gamma and hedge against the move (sell rallies, buy dips): the tape grinds and mean-reverts. Negative net GEX — they hedge with the move (buy strength, sell weakness): moves extend and volatility feeds on itself. That single sign tells you whether today's tape wants to fade or run.
Gamma Flip
The gamma flip is the price where net GEX crosses zero — the dividing line between the two regimes above. Above it, dealers dampen; below it, they amplify. It's the single most important level on the map: when price crosses the flip, the market's whole character can change. We solve for it across the full strike surface, not a single point.
Call Wall & Put Wall
Gamma isn't spread evenly — it clusters at the strikes with the most open interest. The Call Wall is the strike above spot carrying the largest call-gamma concentration; the Put Wall is the largest put-gamma concentration below. In a positive-gamma regime the Call Wall tends to act as a magnet / resistance (a pin) and the Put Wall as support — the levels dealer hedging defends hardest.
Gravity
Gravity is the |gamma|-weighted center of the dealer book — the balance point of all that hedging pressure. In a positive-gamma regime it behaves like a magnet / mean-reversion target: when price stretches away from it, the aggregate of dealer hedging tends to lean price back toward the center. It differs from the gamma flip (a boundary) and from VWAP (built from realized volume) — and when Gravity and VWAP line up, that shared level is unusually sticky. In negative gamma the pull weakens and price can accelerate away from it.
Expected Move
The expected move is the ±1σ range the options market is pricing for the session (and the week) — derived from at-the-money implied volatility.
Expected move = spot × ATM implied vol × √(time)Roughly two-thirds of the time, price stays inside it. It frames every other level: a Call Wall inside the expected move is very different from one a full move away. It's the market's own honest estimate of how far today can go.
Put/Call Skew
Skew is the 25-delta risk reversal — the implied vol of a 25-delta put minus a 25-delta call, in vol points. Because indices fall faster than they rise, puts almost always cost more, so a positive reading is normal — it measures how much downside hedging demand (fear) is bid into the tape. A skew that steepens flags rising hedging; one that flattens or inverts flags complacency or an upside chase.
Sweeps & Blocks
The dealer map tells you where the pressure sits; the print tape tells you who's acting on it. We read the live time-and-sales tape for SPY, QQQ and IWM and tag two things. A sweep is one order deliberately shredded across multiple exchanges at once to get filled immediately — an urgent, aggressive footprint, tagged by which side crossed the spread (call-buying leans bullish, put-buying bearish). A block is a single oversized print — size that moves on conviction, not accident. It's the same tape the flow desks read, computed in-house off the live feed — no third-party flow vendor between you and the print.
Where we draw the line
Everything above is standard, public market-structure analytics — the same class of math every serious options desk publishes. We're transparent about it on purpose: you should understand the read you're paying for.
What you won't find here, by design: how NoVo trades. The entry and exit logic, the scoring that sizes a position, the conditions that decide when the machine acts — that's the proprietary engine behind NoVo Trader, and it stays proprietary. This page is about how we read the market. The edge is in what the system does with it.