BSX· Boston Scientific
Dark pool · off-exchange short volume
Short ratio (latest)
32.4%
20-day average
45.3%
Off-exchange share (20d)
38%
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
49.00
3.71B
48.14
4.72B
47.28
4.34B
46.42
4.70B
45.56
6.23B
44.70
8.89B
43.84
9.04B
42.98
12.8B
42.12
10.2B
41.26
7.02B
40.40
6.09B
39.54
6.04B
38.68
8.39B
37.82
9.34B
36.96
8.56B
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.