| Country | Action | Action Date | Effective Date |
|---|
| Algeria | Extension | 03/01/1922 | |
| ARGENTINE REPUBLIC | Signature | 31/10/1920 | |
| ARGENTINE REPUBLIC | Ratification | 27/12/1921 | |
| AUSTRALIA | Accession | 30/06/1921 | |
| BULGARIA | Signature | 31/10/1920 | |
| CUBA | Signature | 31/10/1920 | |
| Cyrenaica | Extension | 15/10/1923 | |
| EGYPT | Accession | 01/11/1923 | |
| Eritrea | Extension | 15/10/1923 | |
| FRANCE | Signature | 31/10/1920 | |
| FRANCE | Ratification | 03/01/1922 | |
| French Indo-china | Extension | 03/01/1922 | |
| French West Africa | Extension | 03/01/1922 | |
| GREECE | Signature | 31/10/1920 | |
| HUNGARY | Signature | 31/10/1920 | |
| HUNGARY | Ratification | 14/09/1925 | |
| ITALY | Signature | 31/10/1920 | |
| ITALY | Ratification | 15/10/1923 | |
| Madagascar | Extension | 03/01/1922 | |
| MEXICO | Signature | 31/10/1920 | |
| Morocco | Extension | 03/01/1922 | |
| SERB-CROAT-SLOVENE STATE | Signature | 31/10/1920 | |
| SERB-CROAT-SLOVENE STATE | Ratification | 28/08/1925 | |
| Somaliland | Extension | 15/10/1923 | |
| SPAIN | Accession | 07/02/1921 | |
| Tripoli | Extension | 15/10/1923 | |
| Tunis | Extension | 03/01/1922 | |
| UNITED KINGDOM | | | |
| URUGUAY | Signature | 31/10/1920 | |