| Period | Weighting | Quarter | ||||||
|---|---|---|---|---|---|---|---|---|
| Company | Longest | Shortest | Min. | Avg. | Max. | First | Latest | ↓ Count |
| GROUP ONE TRADING, L.P. | 6 | 3 | 0.00% | 0.04% | 0.15% | Q3 2013 | Q4 2015 | 9 |
| SIMPLEX TRADING, LLC | 1 | 1 | 0.05% | 0.05% | 0.05% | Q4 2014 | Q4 2014 | 1 |
This page lists all the filers that currently own ALEXION PHARMACEUTICALS INC or have owned ALEXION PHARMACEUTICALS INC in the past.