Patent protection for an invention is valid for 20 years from the filing date of the patent application. For medicinal products for the treatment of humans and animals, as well as many agricultural chemicals used as plant protection products, a marketing authorisation must be obtained. This procedure is independent from the procedure for the grant of patent. However, patent holders for the pharmaceuticals or the plant protection products, although they have a patent for their product, cannot use it commercially before the marketing authorisation has been obtained. This procedure may last for years.

n the case of patents for the pharmaceuticals or the plant protection products, the duration of protection can be extended for up to five years. This extension of patent protection is called supplementary protection certificate (SPC). The purpose of SPC is to allow proportional compensation to the patent holder for the time that elapses between the date of filing the patent application and the date when the first marketing authorisation in the Republic of Serbia is granted, which is the first day when the patent holder can actually offer his product on the Serbian market.

Supplementary protection certificate refers to the active substance or combination of active substances protected by patent valid in the Republic of Serbia, which has obtained the marketing license issued by the Medicines and Medical Devices Agency of Serbia (ALIMS), or the Plant Protection Directorate of the Ministry of Agriculture, Forestry and Waterworks of the Republic of Serbia.

Certificate does not prolong the basic patent as such, but it refers to the protection according to the patent exclusively for the certain product included in the marketing license for a certain pharmaceutical or the plant protection product.

Request for the certificate is filed by the holder of a basic patent, whose subject matter protected is chemical substance, procedure for the obtaining of that substance or the use of that substance as a pharmaceutical or as the plant protection product.

Certificate is granted to the holder of basic patent protecting active ingredient or his legal successor in title, but not to the holder of license or manufacturer.

Protection according to the granted certificate lasts for the period equal to the period that lapsed from the filing date of the application for a basic patent to the date of the first marketing authorisation to place  the product on the market in the Republic of Serbia, reduced by a period of five years. Duration of protection by certificate starts when the validity of the basic patent lapses and it cannot be longer than five years. For the maintenance of certificate, the holder of the certificate has an obligation to pay annual administrative fees in compliance with the special regulation.