| Name | Ownership | Shares Owned | sole voting power | shared voting power | Signature | Title | CIK |
|---|---|---|---|---|---|---|---|
| Fresenius Medical Care Holdings, Inc. | 11.8% | 18.3M | 0 | 18.3M | /s/ Bryan Mello | Bryan Mello, Vice President and Assistant Treasurer | 0000042872 |
| Fresenius Medical Care AG | 11.8% | 18.3M | 0 | 18.3M | /s/ F. W. Maddux MD | Franklin W. Maddux MD, Member of the Board of Management and Global Chief Medical Officer | 0001333141 |