| Contracting Party | Signature | Instrument | In Force | Details |
|---|
| Albania | | Accession: July 4, 1995 | October 4, 1995 | Details |
| Algeria | | Accession: March 24, 1972 | July 5, 1972 | Details |
| Armenia | | Declaration of Continued Application: May 17, 1994 | December 25, 1991 | Details |
| Austria | | Accession: November 30, 1908 | January 1, 1909 | Details |
| Azerbaijan | | Accession: September 25, 1995 | December 25, 1995 | Details |
| Belarus | | Declaration of Continued Application: April 14, 1993 | December 25, 1991 | Details |
| Belgium | April 14, 1891 | Ratification: June 15, 1892 | July 15, 1892 | Details |
| Bhutan | | Accession: May 4, 2000 | August 4, 2000 | Details |
| Bosnia and Herzegovina | | Declaration of Continued Application: June 2, 1993 | March 1, 1992 | Details |
| Bulgaria | | Accession: April 25, 1985 | August 1, 1985 | Details |
| China | | Accession: July 4, 1989 | October 4, 1989 | Details |
| Croatia | | Declaration / Notification of Succession: July 28, 1992 | October 8, 1991 | Details |
| Cuba | | Accession: September 6, 1989 | December 6, 1989 | Details |
| Cyprus | | Accession: August 4, 2003 | November 4, 2003 | Details |
| Czech Republic | | Declaration of Continued Application: December 18, 1992 | January 1, 1993 | Details |
| Democratic People's Republic of Korea | | Accession: March 7, 1980 | June 10, 1980 | Details |
| Egypt | | Accession: March 5, 1951 | July 1, 1952 | Details |
| France | April 14, 1891 | Ratification: June 15, 1892 | July 15, 1892 | Details |
| Germany | | Accession: October 19, 1922 | December 1, 1922 | Details |
| Guatemala | April 14, 1891 | | | |
| Hungary | | Accession: November 30, 1908 | January 1, 1909 | Details |
| Iran (Islamic Republic of) | | Accession: September 25, 2003 | December 25, 2003 | Details |
| Italy | April 14, 1891 | Ratification: October 15, 1894 | October 15, 1894 | Details |
| Kazakhstan | | Declaration of Continued Application: February 16, 1993 | December 25, 1991 | Details |
| Kenya | | Accession: March 26, 1998 | June 26, 1998 | Details |
| Kyrgyzstan | | Declaration of Continued Application: February 14, 1994 | December 25, 1991 | Details |
| Latvia | | Accession: September 29, 1994 | January 1, 1995 | Details |
| Lesotho | | Accession: November 12, 1998 | February 12, 1999 | Details |
| Liberia | | Accession: September 25, 1995 | December 25, 1995 | Details |
| Liechtenstein | | Accession: May 8, 1933 | July 14, 1933 | Details |
| Luxembourg | | Accession: July 15, 1924 | September 1, 1924 | Details |
| Monaco | | Accession: February 9, 1956 | April 29, 1956 | Details |
| Mongolia | | Accession: January 16, 1985 | April 21, 1985 | Details |
| Montenegro | | Declaration of Continued Application: December 4, 2006 | June 3, 2006 | Details |
| Morocco | | Accession: February 27, 1917 | July 30, 1917 | Details |
| Mozambique | | Accession: July 7, 1998 | October 7, 1998 | Details |
| Namibia | | Accession: March 31, 2004 | June 30, 2004 | Details |
| Netherlands | April 14, 1891 | Accession: March 1, 1893 | March 1, 1893 | Details |
| Poland | | Accession: December 14, 1990 | March 18, 1991 | Details |
| Portugal | April 14, 1891 | Ratification: October 31, 1893 | October 31, 1893 | Details |
| Republic of Moldova | | Declaration of Continued Application: February 14, 1994 | December 25, 1991 | Details |
| Romania | | Accession: August 26, 1920 | October 6, 1920 | Details |
| Russian Federation | | Accession: March 15, 1976 | July 1, 1976 | Details |
| San Marino | | Accession: June 25, 1960 | September 25, 1960 | Details |
| Serbia | | Declaration of Continued Application: September 19, 2006 | April 27, 1992 | Details |
| Sierra Leone | | Accession: March 17, 1997 | June 17, 1997 | Details |
| Slovakia | | Declaration of Continued Application: December 30, 1992 | January 1, 1993 | Details |
| Slovenia | | Declaration of Continued Application: June 12, 1992 | June 25, 1991 | Details |
| Spain | April 14, 1981 | Ratification: June 15, 1892 | July 15, 1892 | Details |
| Sudan | | Accession: February 15, 1984 | May 16, 1984 | Details |
| Swaziland | | Accession: September 14, 1998 | December 14, 1998 | Details |
| Switzerland | April 14, 1891 | Ratification: June 15, 1892 | July 15, 1892 | Details |
| Syrian Arab Republic | | Accession: May 5, 2004 | August 5, 2004 | Details |
| Tajikistan | | Declaration of Continued Application: February 14, 1994 | December 25, 1991 | Details |
| the former Yugoslav Republic of Macedonia | | Declaration / Notification of Succession: July 23, 1993 | September 8, 1991 | Details |
| Ukraine | | Declaration of Continued Application: September 21, 1992 | December 25, 1991 | Details |
| Viet Nam | | Declaration of Continued Application: September 17, 1956 | June 25, 1939 | Details |
