| Country | Action | Action Date | Effective Date |
|---|
| Australia | Signature | 28/06/1919 | |
| Australia | Ratification | 10/01/1920 | |
| Canada | Signature | 28/06/1919 | |
| Canada | Ratification | 10/01/1920 | |
| FRANCE | Signature | 28/06/1919 | |
| FRANCE | Ratification | 10/01/1920 | |
| India | Signature | 28/06/1919 | |
| India | Ratification | 10/01/1920 | |
| ITALY | Signature | 28/06/1919 | |
| ITALY | Ratification | 10/01/1920 | |
| JAPAN | Signature | 28/01/1919 | |
| JAPAN | Ratification | 10/01/1920 | |
| New Zealand | Signature | 28/06/1919 | |
| New Zealand | Ratification | 10/01/1920 | |
| POLAND | Signature | 28/06/1919 | |
| POLAND | Ratification | 10/01/1920 | |
| South Africa | Signature | 28/06/1919 | |
| South Africa | Ratification | 10/01/1920 | |
| UNITED KINGDOM | Signature | 28/06/1919 | |
| UNITED KINGDOM | Ratification | 10/01/1920 | |
| UNITED STATES OF AMERICA | Signature | 28/06/1919 | |
| UNITED STATES OF AMERICA | Ratification | 10/01/1920 | |