| Period | Weighting | Quarter | ||||||
|---|---|---|---|---|---|---|---|---|
| Company | Longest | Shortest | Min. | Avg. | Max. | First | Latest | ↓ Count |
| CONCOURSE FINANCIAL GROUP SECURITIES, INC. | 21 | 21 | 0.00% | 0.00% | 0.00% | Q3 2018 | Q3 2023 | 21 |
| SIMPLEX TRADING, LLC | 5 | 1 | 0.00% | 0.00% | 0.00% | Q1 2017 | Q3 2023 | 13 |
| GROUP ONE TRADING, L.P. | 6 | 2 | 0.00% | 0.00% | 0.00% | Q1 2020 | Q3 2023 | 11 |
This page lists all the filers that currently own SPOK HLDGS INC or have owned SPOK HLDGS INC in the past.