The countries using Plant Variety Certificates are members of UPOV, the International Union for the Protection of New Varieties of Plants.
This intergovernmental organization, established in 1961, defined the legal basis for plant variety protection through an "International Convention for the Protection of New Varieties of Plants", known as the UPOV Convention.
These legal texts are binding for each of the members of UPOV (94 countries to date and unions of countries including the EU). They must incorporate the regulations into their national legislation by issuing Plant Variety Certificates (PVCs).
The UPOV Convention has been amended three times: in 1972, 1978 and in 1991.
The most significant amendment took place in 1991, with the introduction of the concepts of "essentially derived variety" and "farm-saved seed" (possibility for farmers to use farm-saved seed of a protected variety on their own holding).
1991 Act of the International Convention for the Protection of New Varieties of Plants
