COST· Costco

Dark pool · off-exchange short volume

as of 2026-11-05

COST's off-exchange short-volume ratio was 56.2% on 5 Nov 2026, above its 20-day average of 46.4%. Off-exchange trading was 32% of volume over the last 20 sessions. 14 sessions in the last six months had unusually large off-exchange dollar volume, the latest on 2 Nov 2026.

Short ratio (latest)

56.2%

20-day average

46.4%

Off-exchange share (20d)

32%

Darkpool density

big day, short ratio above trendbelow trendbubble size = how unusual ($vol z-score)

Last ~6 months. Bubbles mark days of unusually large off-exchange dollar volume (≥1.5σ vs the trailing 60 days). Daily resolution — not print-level data.

Darkpool levels ±15% of spot, since 2018-10-01

1088.33

1.37B

1067.40

3.02B

1046.47

12.0B

1025.54

17.5B

1004.61

40.4B

983.68

58.4B

962.75

52.8B

941.82

61.8B

920.89

57.8B

899.96

40.5B

Historical off-exchange $ volume at price: each day's volume spread across that day's range, summed over the full FINRA history. Heavy shelves often act as support/resistance magnets. Amber row = spot's bin.

Off-exchange short-volume ratio

short ratio (20d, right) daily off-exchange share (left)

FINRA daily TRF data, last 2 years. A persistently HIGH short ratio is mostly passive market-maker liquidity provision (commonly read as accumulation pressure) — not naively bearish.