ACI Max Pain, Dark Pool & Options Flow

A divergence is when the news narrative and the institutional money flow point in opposite directions — a bearish headline while large call premium is bought, or heavy dark-pool selling under a bullish story. It signals the crowd and the desks may disagree.

Dark-pool volume — The share of trading executed off-exchange, at wholesalers and dark pools. About half of all US share volume prints there on an ordinary day, so the level by itself says almost nothing. What carries information is the distance from this name’s own recent norm, and whether the off-exchange size ran above its usual.

Off-exchange short share — How much of that off-exchange volume was sold short. The median across all listed names is about 49%, because wholesalers filling retail buy orders sell short and cover later. A reading near half is plumbing, not a bearish vote — compare it to the same name’s own 20-day norm.

Max pain — The price where the most options expire worthless — positioning often gravitates toward it near expiry.

Call wall / Put floor — Strikes with the heaviest call/put open interest — they often act as short-term resistance and support.

Put/Call ratio — Below ~0.7 leans bullish (more calls); above ~1 leans defensive (more puts).