| Period | Weighting | Quarter | ||||||
|---|---|---|---|---|---|---|---|---|
| Company | Longest | Shortest | Min. | Avg. | Max. | First | Latest | ↓ Count |
| GROUP ONE TRADING, L.P. | 3 | 2 | 0.00% | 0.00% | 0.01% | Q3 2013 | Q4 2014 | 5 |
| SIMPLEX TRADING, LLC | 1 | 1 | 0.00% | 0.00% | 0.00% | Q4 2014 | Q4 2014 | 1 |
This page lists all the filers that currently own BLACK HILLS CORP or have owned BLACK HILLS CORP in the past.