Patents are exclusive rights granted to inventors that prevent others from making, using, selling or importing the patented invention, for a term of at least 20 years. The criteria for granting patents are novelty, inventiveness and industrial applicability.

Article 27 of the TRIPs agreement establishes what can be patented and the scope for exceptions:

1. Subject to the provisions of paragraphs 2 and 3, patents shall be available for any inventions
   ... whether products or processes, in all fields of technology, provided that they are new, involve an inventive step and are capable of industrial application. … patents shall be available and patent rights enjoyable without discrimination as to the place of invention, the field of technology and whether products are imported or locally produced.
2. Members may exclude from patentability inventions
   ... the prevention within their territory of the commercial exploitation of which is necessary to protect ordre public or morality, including to protect human, animal or plant life or health or to avoid serious prejudice to the environment, provided that such exclusion is not made merely because the exploitation is prohibited by their law.
3. Members may also exclude from patentability:
   (a) plants and animals other than micro-organisms, and
   (b) essentially biological processes for the production of plants or animals other than non-biological and microbiological processes.
   However, Members shall provide for the protection of plant varieties either by patents or by an effective sui generis system or by any combination thereof.
   
   

In addition to Article 27.3(b), the TRIPS Agreement contains two general provisions that may limit patent rights. One is specified in Article 30, which allows Member to provide limited exceptions to the exclusive rights conferred by patents "provided that such exceptions to do not unreasonably conflict with a normal exploitation of the patent and do not unreasonably prejudice the legitimate interests of the patent owner, taking into account the legitimate interests of third parties.” Secondly, Article 31 allows Members to issue "compulsory licenses", whereby use is made of the subject matter of the patent without the authorisation of the rights holder. Several conditions are placed on the use of this instrument, including:

• Such an authorisation should be based on a consideration of individual merits;
• The proposed user will have made efforts over a reasonable period of time to secure a voluntary license on reasonable commercial terms, except in cases of national emergency, extreme urgency or public non-commercial use
• The right holder will be paid adequate remuneration
• The legal validity of the license and the remuneration will be subject to judicial or other forms of independent review.

Even though such licenses have recently been granted in the field of pharmaceuticals in developing countries, there is little practice in implementing these limitations for purposes relating to the conservation of genetic resources. It should be emphasised, however, that in conformity with general rules of international law, such limitations and exceptions are to be interpreted narrowly so as not to interfere with the object and purpose of the treaty. Patents are a rather rigid form of protection and most often apply to innovations in industrialized countries. As an alternative, most developing countries have a PBR systems in place. As natonal and international agricultural research centres are confronted with both systems, it can be useful to make a comparison. In this comparison we use 1991 UPOV as the standard. PBR (1991 UPOV) and both offer exclusive rights in other words they entitle the holder to exclude others from performing certain acts with the patented or protected subject matter. The common objective is to provide an incentive for the development of innovative and useful products or processes. The utility patent system covers inventions in all fields of technology whereas PVP and plant patent systems are specifically developed to cover plant varieties. A comparison of PVP and patents is summarised in this table.

DUS and VCU

The UPOV-based national laws for the protection of plant varieties differ significantly from the patent system with regard to the conditions for protection (distinctness, homogeneity, stability, novelty and nomenclature: DUS-NN (or simply DUS). DUS standards are adapted to the mode of reproduction of the variety and relate to the average of the existing varieties. For example, cross-fertilizing crops have a wide tolerance applied for uniformity, while requirements are very strict for vegetatively propagated crops. An applicant variety is considered new under PVP when it has not been offered for sale (anywhere in the world). There is furthermore no requirement for utility, such as a positive result of testing for the so-called Value for Cultivation and Use (VCU).

Breeders’ Exemption

Using the protected variety for breeding purposes, the so called "breeders' exemption" is a fundamental aspect of the UPOV system of PVP and makes it essentially different from the patent system. Patents do not allow further use of the patented material for R&D except for research on the subject matter itself. This provision in PVP is based on the assumption that real progress in breeding can best be made by incorporating the newest, released material in new breeding programmes plus all earlier released materials such as modern varieties, local varieties, land races and wild species. Further reading on Breeders’ Exemption.

Breeders’ exemption in greater detail

Under a PVP system a new variety can be "built" on an existing, protected variety and be eligible for PVP as long as it complies to the requirements for novelty, distinctness, uniformity and stability. Only in cases where the protected variety has been changed in one or few aspects, the breeder of a new variety has to seek the consent of the holder of the rights on the original variety. The new variety is then called ‘essentially derived’ from an existing variety. The Breeder’s Exemption is also a matter of discussion within the breeding industry itself.

There are major differences between the breeder’s exemption under PVP and the so-called research exemption in utility patent systems. There is much debate on the research exemption in the patent systems of several countries. Academic institutions have long been exempted
from patent claims for their research and education purposes based on the assumption that such research had no commercial intent. In several countries such research exemptions are specifically included in the law; in others such as the USA it is an interpretation of clauses on private and non-commercial use provisions.The situation is under discussion as the result of a number of court rulings. Maley v. Duke in the USA seems to result in a restriction of opportunities to use patented products or processes for research, and indicates that scientists need a research license to use them. The research exemption would only apply to research on the invention, and not researching with the invention. Research licenses are commonly granted without the payment of royalties, but specify the rights of the patent holder in case the research leads to something useful. Such interpretation would mean that a PVP-protected variety that is available for further breeding cannot be used when it contains a patented gene. In the European Union, this conflict between patents and PVP is solved by providing a specific breeder’s exemption and a farmers’ privilege in the patent system when the scope of the patent would extend to a plant variety.

Farmers’ privilege

In the 1978 UPOV act, the scope of PBR did not extend to the propagation of protected varieties for replanting purposes by farmers. This 'on-farm seed saving' was considered not to be a commercial activity, thus falling beyond the scope of PBR. Later, on-farm seed saving would be referred to as the 'farmers' privilege' (or the 'crop exemption'). The farmers’ privilege is very important, since it provides the legal boundaries of the rights what farmers’ use is concerned. Depending on the national law and its interpretation, farmers are allowed to save and/or exchange seed of the protected materials, or these acts are restricted. Since local seed systems depend in the free exchange of varieties, several developing countries have opted for a wide interpretation of the farmers’ privilege, which is not in compliance with UPOV 1991.