PSNL Dark Pool Activity
Personalis, Inc.
Data as of Oct 23, 2026 · Source: FINRA daily short sale volume (off-exchange)
On Oct 23, 2026, FINRA reported 331K PSNL shares in publicly disseminated off-exchange trades (dark pools and other off-exchange venues). 179K of those shares (54.0%) were marked short or short-exempt, above PSNL's 30-day rolling average of 39.0% (z-score 1.21). Over the last 10 FINRA sessions (Oct 12, 2026 – Oct 23, 2026), PSNL's off-exchange short volume ratio ranged from 22.1% to 73.5% and averaged 42.4%; the latest reading is above that 10-session average.
Off-Exchange Volume
331K
Short Volume
179K
Short Volume Ratio
54.0%
30-Day Average
39.0%
z-score 1.21
Daily readings — last 10 FINRA sessions
| Date | Off-exchange shares | Short shares | Short ratio |
|---|---|---|---|
| Oct 12, 2026 | 1.2M | 279K | 22.7% |
| Oct 13, 2026 | 2.0M | 436K | 22.1% |
| Oct 14, 2026 | 1.6M | 473K | 29.2% |
| Oct 15, 2026 | 864K | 325K | 37.6% |
| Oct 16, 2026 | 1.6M | 588K | 36.5% |
| Oct 19, 2026 | 1.5M | 653K | 44.0% |
| Oct 20, 2026 | 1.0M | 542K | 51.6% |
| Oct 21, 2026 | 1.1M | 561K | 53.0% |
| Oct 22, 2026 | 959K | 705K | 73.5% |
| Oct 23, 2026 Latest | 331K | 179K | 54.0% |
Source: FINRA daily short sale volume (off-exchange). Ratio = ShortVolume ÷ TotalVolume for the day.
PSNL dark pool FAQ
- How much PSNL off-exchange volume did FINRA report on Oct 23, 2026?
- FINRA's daily short sale volume file reported 331K PSNL shares in publicly disseminated off-exchange trades on Oct 23, 2026; 179K of those shares (54.0%) were marked short or short-exempt.
- Is PSNL's dark pool short volume ratio unusual right now?
- As of Oct 23, 2026, PSNL's short volume ratio of 54.0% is above PSNL's 30-day rolling average of 39.0% (z-score 1.21). 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.