| Country | Action | Action Date | Effective Date |
|---|
| Antigua | Extension | 20/01/1913 | |
| ARGENTINE REPUBLIC | Accession | | 15/04/1922 |
| ARGENTINE REPUBLIC | Signature | 23/09/1910 | |
| Australia | Extension | 09/09/1930 | 24/10/1930 |
| AUSTRIA-HUNGARY | Declaration | 01/01/1905 | |
| AUSTRIA-HUNGARY | Signature | 23/09/1910 | |
| AUSTRIA-HUNGARY | Ratification | 01/02/1913 | |
| Bahamas | Extension | 20/01/1913 | |
| Barbados | Extension | 20/01/1913 | |
| BELGIUM | Signature | 23/09/1910 | |
| BELGIUM | Ratification | 01/02/1913 | |
| Bermuda | Extension | 20/01/1913 | |
| BRAZIL | Signature | 23/09/1910 | |
| BRAZIL | Ratification | 31/12/1913 | |
| British East Africa | Extension | 20/01/1913 | |
| British Guiana | Extension | 20/01/1913 | |
| British Honduras | Extension | 20/01/1913 | |
| British Solomon Islands | Extension | 20/01/1913 | |
| British Virgin Islands | Extension | 20/01/1913 | |
| Canada | Extension | 25/09/1914 | |
| Cayman Islands | Extension | 20/01/1913 | |
| Ceylon | Extension | 20/01/1913 | |
| CHILE | Signature | 23/09/1910 | |
| CHINA | Accession | 28/09/1994 | 18/11/1994 |
| CONGO | Accession | 17/07/1967 | |
| CROATIA | Succession | 30/07/1992 | 08/10/1991 |
| CUBA | Signature | 23/09/1910 | |
| Cyprus | Extension | 20/01/1913 | |
| DANZIG | Accession | 15/07/1922 | |
| DENMARK | Signature | 23/09/1910 | |
| DENMARK | Ratification | 18/06/1913 | |
| Dominica | Extension | 20/01/1913 | |
| DOMINICAN REPUBLIC | Accession | 23/07/1958 | |
| EGYPT | Accession | | 01/01/1944 |
| ESTONIA | Accession | 20/02/1930 | |
| Falkland Island Dependencies | Extension | 20/01/1913 | |
| Falkland Islands | Extension | 20/01/1913 | |
| Fiji | Extension | 20/01/1913 | |
| FIJI | Succession | 22/08/1972 | 10/10/1970 |
| FINLAND | Accession | 28/08/1923 | |
| FRANCE | Signature | 23/09/1910 | |
| FRANCE | Ratification | 01/02/1913 | |
| GERMAN DEMOCRATIC REPUBLIC | Re-Application | 27/12/1954 | |
| GERMANY | Signature | 23/09/1910 | |
| GERMANY | Ratification | 01/02/1913 | |
| GERMANY FEDERAL REPUBLIC | Re-Application | 01/01/1953 | |
| Gibraltar | Extension | 20/01/1913 | |
| Gilbert & Ellice Colony | Extension | 20/01/1913 | |
| Gold Coast | Extension | 20/01/1913 | |
| GREECE | Signature | 23/09/1910 | |
| GREECE | Ratification | 29/09/1913 | |
| Grenada | Extension | 20/01/1913 | |
| HAYTI | Accession | 15/10/1951 | |
| Hong Kong | Extension | 20/01/1913 | |
| HONG KONG SAR | Application | 04/06/1997 | 01/07/1997 |
| India | Extension | 20/01/1913 | |
| IRAN | Accession | 26/04/1966 | |
| Italian Colonies | Accession | 05/01/1935 | |
| ITALY | Signature | 23/09/1910 | |
| ITALY | Ratification | 02/06/1913 | |
| Jamaica | Extension | 20/01/1913 | |
| JAPAN | Signature | 23/09/1910 | |
| JAPAN | Ratification | 12/01/1914 | |
| LATVIA | Accession | 16/09/1932 | |
| Leeward Islands | Extension | 20/01/1913 | |
| LUXEMBOURG | Accession | 18/02/1991 | 18/03/1991 |
| MALAGASY REPUBLIC | Succession | 13/07/1965 | |
| Malay States, Federated | Extension | 20/01/1913 | |
| Malta | Extension | 20/01/1913 | |
| Mauritius | Extension | 20/01/1913 | |
| MEXICO | Signature | 23/09/1910 | |
| MEXICO | Ratification | 01/02/1913 | |
| Montserrat | Extension | 20/01/1913 | |
| NETHERLANDS THE | Signature | 23/09/1910 | |
| NETHERLANDS THE | Ratification | 01/02/1913 | |
| New Zealand | Extension | 19/05/1913 | |
| Newfoundland (UK) | Extension | 11/04/1914 | |
| NICARAGUA | Signature | 23/09/1910 | |
| NICARAGUA | Ratification | 18/07/1913 | |
| Nigeria, South | Extension | 20/01/1913 | |
| Norfolk Island | Extension | 20/01/1913 | |
| Norfolk Island | Extension | 09/09/1930 | |
| NORWAY | Signature | 23/09/1910 | |
| NORWAY | Ratification | 12/11/1913 | |
| Papua | Extension | 20/01/1913 | |
| Papua | Extension | 09/09/1930 | |
| PAPUA NEW GUINEA | Succession | 16/09/1975 | |
| PARAGUAY | Accession | 22/11/1967 | |
| POLAND | Accession | 15/07/1922 | |
| PORTUGAL | Signature | 23/09/1910 | |
| PORTUGAL | Ratification | 25/07/1913 | |
| PORTUGAL | Communication | 23/09/1999 | |
| ROUMANIA | Signature | 23/09/1910 | |
| ROUMANIA | Ratification | 01/02/1913 | |
| RUSSIA | Signature | 23/09/1910 | |
| RUSSIA | Ratification | 01/02/1913 | |
| SAINT LUCIA | Succession | 09/03/1990 | |
| Seychelles | Extension | 20/01/1913 | |
| Sierra Leone | Extension | 20/01/1913 | |
| SINGAPORE | Succession | 31/05/1974 | 09/08/1965 |
| SLOVENIA | Succession | 13/10/1993 | 25/06/1991 |
| SOLOMON ISLANDS | Succession | 17/09/1981 | |
| Somaliland | Extension | 20/01/1913 | |
| SOVIET UNION | Accession | | 27/08/1936 |
| SPAIN | Signature | 23/09/1910 | |
| SPAIN | Accession | 30/12/1923 | |
| St Christopher, Nevis and Anguilla | Extension | 20/01/1913 | |
| St Helena | Extension | 20/01/1913 | |
| St Lucia | Extension | 20/01/1913 | |
| St Vincent | Extension | 20/01/1913 | |
| ST VINCENT AND THE GRENADINES | Succession | 06/02/2002 | 28/10/1979 |
| Straits Settlements | Extension | 20/01/1913 | |
| SWITZERLAND | Accession | 26/05/1954 | 15/08/1954 |
| The Gambia | Extension | 20/01/1913 | |
| TONGA | Accession | 13/06/1978 | 30/07/1978 |
| Trinidad And Tobago | Extension | 20/01/1913 | |
| TURKEY | Accession | 04/07/1955 | |
| Turks And Caicos Islands | Extension | 20/01/1913 | |
| UNITED KINGDOM | Signature | 23/09/1910 | |
| UNITED KINGDOM | Ratification | 01/02/1913 | |
| UNITED KINGDOM | Re-Application | 01/01/1953 | |
| UNITED STATES OF AMERICA | Signature | 23/09/1910 | |
| URUGUAY | Signature | 23/09/1910 | |
| URUGUAY | Accession | 24/07/1915 | |
| Weihaiwei | Extension | 20/01/1913 | |
| YUGOSLAVIA | Accession | 12/02/1932 | |