The basic task of the European Patent Convention (EPC) is to grant patent protection using a single European procedure for the grant of patents on the basis of a single European patent application and create a uniform body of substantive patent law designed to provide easier, cheaper and stronger protection for inventions in the EPC contracting states. A patent granted under the EPC is called European patent. It has a territorial effect and may ensure protection in the territories of all 38 EPC contracting states. In each contracting state for which European Patent is granted, the latter gives its proprietor the same rights as would be conferred by a national patent granted in that contracting state. European patents may also be effective in 4 additional countries that have not acceded to the EPC, so-called extension and validation states. At present these are Bosnia-Herzegovina and Montenegro (extension states) and Morocco and the Republic of Moldova (validation states).
The term of validity of a European patent is 20 years as from the date of filing of the European patent application.
Bulgaria has been a member of EPC since 1 July 2002. A granted European patent shall have effect in the territory of Bulgaria if the latter is designated in the European patent application and if, within 3 months following the publication in the European Patent Bulletin of the decision to grant a European patent pursuant to Art. 97(1) EPC, a full translation of the European patent description and claims into Bulgarian is filed with the Bulgarian Patent Office (BPO) and the publication fee is paid, i.e. the so-called European patent validation in Bulgaria.