| Country | Action | Action Date | Effective Date |
|---|
| AUSTRIA | Signature | 27/06/1958 | |
| BELGIUM | Signature | 27/06/1958 | |
| BELGIUM | Ratification | 22/07/1960 | |
| DENMARK | Signature | 27/06/1958 | |
| DENMARK | Ratification | 22/09/1958 | |
| FRANCE | Signature | 27/06/1958 | |
| GERMANY FEDERAL REPUBLIC | Signature | 27/06/1958 | |
| GREECE | Signature | 27/06/1958 | |
| ICELAND | Signature | 27/06/1958 | |
| IRELAND, REPUBLIC OF | Signature | 27/06/1958 | |
| IRELAND, REPUBLIC OF | Reservation | 27/06/1958 | |
| ITALY | Signature | 27/06/1958 | |
| ITALY | Ratification | 27/06/1961 | |
| LUXEMBOURG | Signature | 27/06/1958 | |
| NETHERLANDS THE | Signature | 27/06/1958 | |
| NORWAY | Signature | 27/06/1958 | |
| PORTUGAL | Signature | 27/06/1958 | |
| SWEDEN | Signature | 27/06/1958 | |
| SWEDEN | Ratification | 21/01/1959 | |
| SWITZERLAND | Signature | 27/06/1958 | |
| SWITZERLAND | Ratification | 17/07/1958 | |
| TURKEY | Signature | 27/06/1958 | |
| UNITED KINGDOM | Signature | 27/06/1958 | |