OST Dark Pool Activity
ATS off-exchange volume intelligence · Week of 2025-09-08
OST dark pool volume for the week of 2025-09-08: 3.3K shares traded across 12 ATS venues with a total notional value of $6K. Volume is up 81.3% week-over-week. Primary routing venues include , UBS ATS, CBX.
Dark pool activity in OST reflects institutional order flow executing on Alternative Trading Systems (ATS) registered with the SEC — private venues where large-block trades are matched away from public exchanges to minimize price impact. StonkWhisper ingests FINRA-published ATS volume data to track these off-exchange flows. Sustained elevation in dark pool percentage — particularly when concentrated at specific venues — can indicate institutional accumulation or distribution ahead of significant price moves. The interactive charts below show 12-week historical volume and complete venue breakdown for OST.
Weekly History
| Week | Shares | DP % | WoW |
|---|---|---|---|
| 2025-09-08 | 3.3K | — | +81.3% |
| 2025-09-01 | 1.8K | — | -75.9% |
| 2025-08-25 | 7.5K | — | -60.9% |
| 2025-08-18 | 19.2K | — | -41.1% |
| 2025-08-11 | 32.6K | — | -15.4% |
| 2025-08-04 | 38.6K | — | -91.4% |
| 2025-07-28 | 446.4K | — | +31.3% |
| 2025-07-21 | 340.0K | — | -5.6% |
| 2025-07-14 | 360.1K | — | -74.4% |
| 2025-07-07 | 1.4M | — | -84.9% |
| 2025-06-30 | 9.3M | 46.0% | +81.8% |
| 2025-06-23 | 5.1M | 57.4% | +169.9% |