| Relationships | Role | Relationship Start | Relationship End |
| Gs Capital Partners 2000, L.P. | Parent | 9/21/2008 | |
| Gscp 2000 Ngp Holdings Corp. | Parent | 9/21/2008 | |
| Gscp 2000 Offshore Ngp Holdings, L.P. | Subsidary | 9/21/2008 | |
| Gscp 2000 Germany Ngp Holdings, L.P. | Subsidary | 9/21/2008 |