Patent protection of living organisms – and the substances derived therefrom – has long been an area of confusion and controversy in South African patent law. However, there has been a recent move towards clearer boundaries regarding what constitutes patentable subject matter in relation to living things. For example, in Association for Molecular Pathology v Myriad Genetics the US Supreme Court definitively held that "A naturally occurring DNA segment is a product of nature and not patent eligible merely because it has been isolated". The Supreme Court's decision was similar to that in Australia.

By contrast, the patentability of isolated genetic sequences is expressly recognised under Article 5 of the EU Biotechnology Directive.

This article explores the approach taken under South African law.

Patentability under South African law


The Patents Act specifically excludes certain subject matter from patentability. This includes "a method of treatment of the human or animal body by surgery or therapy or diagnosis practiced on the human or animal body". However, drugs, devices and instruments for performing such a method of treatment are still patentable.

The act also excludes "any variety of animal or plant or any essentially derived biological process for the production of animals or plants, not being a microbiological process or the product of such a process". However, there is no case law or directives on what constitutes an essentially derived biological process. Similar uncertainty exists in relation to the definition of a microbiological process or the product of such a process.

Despite the legal uncertainty around subject matter exclusions, there are a few guidelines that can be followed, as discussed below.

Gene sequences

Gene sequences are likely patentable under South African law. This is almost certainly the case if they are not slavish copies of naturally occurring nucleotide sequences. Similarly, biomolecules derived from natural sources (eg, antibodies and enzymes) are most likely patentable, provided that they are isolated and characterised for a specific use. This is in line with the existing approach to drugs derived from plant or animal extracts.


Microbes are patentable under South African law, although the distinction between what constitutes a microbiological process or a product thereof will undoubtedly remain a bone of contention for the foreseeable future. A substantial grey area thus exists as to whether a genetically modified, fertilised plant or animal egg, embryo or cell culture is patentable. The answer to this question may depend on whether the specific method of the invention can be characterised as an in vitro one or whether the invention requires an in vivo step that could reasonably be characterised as an essentially biological process to produce a plant or animal.

Tissues and organs

It is well established that tissues and organs isolated from humans or animals could be patented in certain contexts (including methods of surgery, therapy or diagnosis), as these do not constitute the human or animal body, as set out in the act. Read with the proviso relating to drugs, devices and instruments, this leads to the conclusion that the removal and culturing of cells for the purpose of surgery, therapy or diagnosis is patentable even where their subsequent reintroduction (as in CAR-T therapies) is not patentable by itself.


Finally, as the act clearly prohibits the patenting of varieties of animals or plants, this has led to a longstanding issue whereby genetically modified hybrid crops (which would ordinarily be protected under the aegis of plant breeders' rights) are excluded from being patented and becoming protected varieties for technical reasons. The result is a complicated work around where the parent lines of the hybrid are protected via plant breeders' rights and the genetic constructs used to make it (as well as any accessory microorganisms used in the process) are protected under patents. Something similar may also be true of genetically modified animals, such as knock-out mice – with the mice themselves being non-patentable but the genetic constructs and the processes used to produce them being patentable.

This article was first published by the International Law Office, a premium online legal update service for major companies and law firms worldwide. Register for a free subscription.