| Relationships | Role | Relationship Start | Relationship End |
| Suez Lyonnaise Des Eaux | Parent | 12/31/1992 | 12/30/1994 |
| Metallgesellschaft Corp. | Parent | 12/31/1991 | 12/30/1993 |
| Metallgesellschaft Corp. | Parent | 12/31/1989 | 12/30/1991 |
| Metallgesellschaft Corp. | Parent | 10/31/1985 | 12/30/1989 |