MKTX Dark Pool Activity
Marketaxess Holdings Inc
Data as of Oct 23, 2026 · Source: FINRA daily short sale volume (off-exchange)
On Oct 23, 2026, FINRA reported 213K MKTX shares in publicly disseminated off-exchange trades (dark pools and other off-exchange venues). 104K of those shares (48.9%) were marked short or short-exempt, above MKTX's 30-day rolling average of 39.4% (z-score 0.97). Over the last 10 FINRA sessions (Oct 12, 2026 – Oct 23, 2026), MKTX's off-exchange short volume ratio ranged from 22.0% to 48.9% and averaged 35.9%; the latest reading is above that 10-session average.
Off-Exchange Volume
213K
Short Volume
104K
Short Volume Ratio
48.9%
30-Day Average
39.4%
z-score 0.97
Daily readings — last 10 FINRA sessions
| Date | Off-exchange shares | Short shares | Short ratio |
|---|---|---|---|
| Oct 12, 2026 | 96K | 21K | 22.0% |
| Oct 13, 2026 | 129K | 53K | 41.3% |
| Oct 14, 2026 | 156K | 46K | 29.1% |
| Oct 15, 2026 | 174K | 77K | 44.4% |
| Oct 16, 2026 | 127K | 32K | 25.3% |
| Oct 19, 2026 | 340K | 157K | 46.2% |
| Oct 20, 2026 | 181K | 67K | 36.8% |
| Oct 21, 2026 | 161K | 63K | 39.4% |
| Oct 22, 2026 | 702K | 177K | 25.3% |
| Oct 23, 2026 Latest | 213K | 104K | 48.9% |
Source: FINRA daily short sale volume (off-exchange). Ratio = ShortVolume ÷ TotalVolume for the day.
MKTX dark pool FAQ
- How much MKTX off-exchange volume did FINRA report on Oct 23, 2026?
- FINRA's daily short sale volume file reported 213K MKTX shares in publicly disseminated off-exchange trades on Oct 23, 2026; 104K of those shares (48.9%) were marked short or short-exempt.
- Is MKTX's dark pool short volume ratio unusual right now?
- As of Oct 23, 2026, MKTX's short volume ratio of 48.9% is above MKTX's 30-day rolling average of 39.4% (z-score 0.97). Meridian's dark pool model does not flag this reading as an anomaly.
- What does the dark pool short volume ratio measure?
- FINRA publishes daily short sale volume for trades reported off-exchange to its trade reporting facilities, which include dark pools and other off-exchange venues. The ratio divides FINRA's ShortVolume figure, which counts both short and short-exempt sales, by the total off-exchange shares reported for that day. It is not short interest and not a directional signal: market-maker hedging and reporting mechanics can raise it, so it is context for other signals.