| Country | Action | Action Date | Effective Date |
|---|---|---|---|
| BELGIUM | Signature | 10/05/1950 | |
| CANADA | Signature | 10/05/1950 | |
| CUBA | Accession | 24/10/1951 | |
| DENMARK | Signature | 10/05/1950 | |
| HAITI | Accession | 24/10/1951 | |
| HONDURAS | Accession | 06/10/1951 | |
| LUXEMBOURG | Signature | 10/05/1950 | |
| NETHERLANDS THE | Signature | 10/05/1950 | |
| NICARAGUA | Accession | 23/10/1951 | |
| UNITED KINGDOM | |||
| UNITED STATES OF AMERICA | Signature | 10/05/1950 |