| Country | Action | Action Date | Effective Date |
|---|---|---|---|
| BELGIUM | Signature | 30/04/1976 | |
| DENMARK | Signature | 28/04/1976 | |
| EUROPEAN SPACE RESEARCH ORGANISATION | Signature | 06/04/1976 | |
| EUROPEAN SPACE RESEARCH ORGANISATION | Approval | 19/08/1976 | |
| FRANCE | Signature | 29/07/1976 | |
| GERMANY FEDERAL REPUBLIC | Signature | 06/04/1976 | |
| ITALY | Signature | 30/04/1976 | |
| NETHERLANDS THE | Signature | 29/04/1976 | |
| SPAIN | Signature | 30/06/1976 | |
| SWEDEN | Signature | 30/04/1976 | |
| UNITED KINGDOM | Signature | 23/03/1976 |