| Country | Action | Action Date | Effective Date |
|---|---|---|---|
| BELGIUM | Signature | 16/06/1926 | |
| Canada | Signature | 16/06/1926 | |
| DENMARK | Signature | 16/06/1926 | |
| FRANCE | Signature | 16/06/1926 | |
| GERMANY | Signature | 16/06/1926 | |
| ITALY | Signature | 16/06/1926 | |
| JAPAN | Signature | 16/06/1926 | |
| NETHERLANDS THE | Signature | 16/06/1926 | |
| NORWAY | Signature | 16/06/1926 | |
| SPAIN | Signature | 16/06/1926 | |
| SWEDEN | Signature | 16/06/1926 | |
| UNITED KINGDOM | Signature | 16/06/1926 | |
| UNITED STATES OF AMERICA | Signature | 16/06/1926 |