Definition. The total trading volume (in USD) of all futures contracts, including both expiry and perpetual contracts, where sellers were the aggressors, summed within the intraday window set by the chosen data resolution (e.g. 10-minute, hourly).

Technical. Only trades quoted against USD-related currencies (fiat and stablecoins) on the native asset are included.

Interpretation. Surfaces intraday sell-side flow across all futures, reading as a measure of immediate selling pressure and short-term market sentiment that can inform near-term directional reads.