| Country | Action | Action Date | Effective Date |
|---|
| BELGIUM | Definitive Signature | 01/12/1960 | |
| DENMARK | Definitive Signature | 01/12/1960 | |
| FRANCE | Signature | 01/12/1960 | |
| FRANCE | Ratification | 27/01/1961 | |
| GERMANY | Definitive Signature | 27/02/1961 | |
| ITALY | Signature | 01/12/1960 | |
| ITALY | Ratification | 22/12/1962 | |
| NETHERLANDS THE | Definitive Signature | 01/12/1960 | |
| NORWAY | Definitive Signature | 01/12/1960 | |
| SPAIN | Signature | 01/12/1960 | |
| SPAIN | Ratification | 20/10/1961 | |
| SWEDEN | Definitive Signature | 01/12/1960 | |
| SWITZERLAND | Signature | 01/12/1960 | |
| SWITZERLAND | Ratification | 24/02/1961 | |
| UNITED KINGDOM | Signature | 01/12/1960 | |
| UNITED KINGDOM | Definitive Signature | 01/12/1960 | |