| Country | Action | Action Date | Effective Date |
|---|
| BELGIUM | Signature | 22/06/1955 | |
| BELGIUM | Notification | 21/11/1955 | |
| CANADA | Signature | 22/06/1955 | |
| CANADA | Notification | 30/08/1955 | |
| DENMARK | Signature | 22/06/1955 | |
| DENMARK | Notification | 30/11/1955 | |
| FRANCE | Signature | 22/06/1955 | |
| FRANCE | Notification | 14/11/1955 | |
| GERMANY FEDERAL REPUBLIC | Signature | 22/06/1955 | |
| GERMANY FEDERAL REPUBLIC | Notification | 06/12/1955 | |
| GREECE | Signature | 22/06/1955 | |
| GREECE | Notification | 02/12/1955 | |
| ICELAND | Signature | 22/06/1955 | |
| ICELAND | Notification | 16/01/1956 | |
| ITALY | Signature | 22/06/1955 | |
| ITALY | Notification | 23/09/1955 | |
| LUXEMBOURG | Signature | 22/06/1955 | |
| LUXEMBOURG | Notification | 23/07/1955 | |
| NETHERLANDS THE | Signature | 22/06/1955 | |
| NETHERLANDS THE | Notification | 04/01/1956 | |
| NORWAY | Signature | 22/06/1955 | |
| NORWAY | Notification | 06/12/1955 | |
| PORTUGAL | Signature | 22/06/1955 | |
| PORTUGAL | Notification | 02/12/1955 | |
| TURKEY | Signature | 22/06/1955 | |
| TURKEY | Notification | 29/03/1956 | |
| UNITED KINGDOM | Signature | 22/06/1955 | |
| UNITED KINGDOM | Ratification | 21/10/1955 | |
| UNITED KINGDOM | Notification | 21/10/1955 | |
| UNITED STATES OF AMERICA | Signature | 22/06/1955 | |
| UNITED STATES OF AMERICA | Notification | 28/12/1955 | |