Bullish flow / bearish flow
A scanner's directional label for a trade, inferred from the option type and the execution side. It does not reveal the trader's full position.
A call bought at the ask or a put sold at the bid is usually labeled bullish, and a put bought at the ask or a call sold at the bid is usually labeled bearish. The label depends on the execution-side inference being right and on the trade being a standalone position.
Hedges, spreads, rolls and closing trades can all carry a directional label that is the opposite of the participant’s view. Adding many prints into bullish and bearish premium gives a rough picture of how the tape leans, with the same caveats applied to every print.
Illustrative example (hypothetical numbers, not a real trade): a fund long 100,000 shares buys 1,000 puts at the ask to hedge. A scanner labels the print bearish, while the fund’s combined position is still long the stock.