| Country | Action | Action Date | Effective Date |
|---|
| AUSTRIA | Signature | 11/07/1952 | |
| AUSTRIA | Ratification | 17/05/1957 | |
| BELGIUM | Signature | 11/07/1952 | |
| BELGIUM | Ratification | 24/08/1953 | |
| DENMARK | Signature | 11/07/1952 | |
| DENMARK | Ratification | 05/11/1952 | |
| FRANCE | Signature | 11/07/1952 | |
| GERMANY FEDERAL REPUBLIC | Signature | 11/07/1952 | |
| GREECE | Signature | 11/07/1952 | |
| ICELAND | Signature | 11/07/1952 | |
| IRELAND, REPUBLIC OF | Signature | 11/07/1952 | |
| IRELAND, REPUBLIC OF | Ratification | 10/11/1953 | |
| ITALY | Signature | 11/07/1952 | |
| ITALY | Ratification | 29/10/1956 | |
| LUXEMBOURG | Signature | 11/07/1952 | |
| NETHERLANDS THE | Signature | 11/07/1952 | |
| NETHERLANDS THE | Ratification | 23/10/1953 | |
| NORWAY | Signature | 11/07/1952 | |
| NORWAY | Ratification | 10/02/1953 | |
| PORTUGAL | Signature | 11/07/1952 | |
| SWEDEN | Signature | 11/07/1952 | |
| SWEDEN | Ratification | 24/02/1953 | |
| SWITZERLAND | Signature | 11/07/1952 | |
| SWITZERLAND | Ratification | 30/07/1952 | |
| TRIESTE UK-US ZONE | Signature | 11/07/1952 | |
| TRIESTE UK-US ZONE | Ratification | 13/10/1952 | |
| TURKEY | Signature | 11/07/1952 | |
| TURKEY | Ratification | 30/09/1953 | |
| UNITED KINGDOM | Signature | 11/07/1952 | |
| UNITED KINGDOM | Ratification | 21/01/1955 | 01/01/1900 |