A patent strategy is vitally important to any business and a balance needs to be found between being cost effective and obtaining the most protection possible. It is often advantageous to file a provisional patent application, including for the numerous different components of an invention. These components could be new inventions in themselves and, instead of linking separate components to a single invention, capable of separate patent protection. This gives the patentee better protection.

A basic rule of patent law is unity of invention. While a lack of unity is not grounds for revocation of a patent in South Africa, the Act states that a patent may only be granted for a single invention. If a patent application contains several inventions not linked in any way, there would be lack of unity. The filing of a divisional patent application therefore offers the applicant the option of obtaining patent protection for different inventions originally disclosed in a single patent application (the main or parent application) without risking invalidation by virtue of anticipation. In South African Patent Law, divisional applications must be filed at any time prior to acceptance of the parent application and must then be ante-dated to a date not earlier than the date on which the parent application was filed. Patent term extensions are not possible and the divisional application will expire at the same time as the parent application. Filing of continuation or continuation-in-part applications is also not provided for, although the law does provide for the filing of a patent of addition.

Further, South African patent law does not specifically exclude cascades of divisional applications, that is, the filing of a divisional application on the basis of another divisional application. However, legislation is unclear on whether a divisional filed from a parent divisional can be ante-dated to the lodgement date of the first parent application, which may introduce a risk of invalidation by virtue of anticipation. The direct parent application must still be pending in order to be able to file a second divisional.

When filing a divisional application the matter therein must be directed to part of the matter disclosed in the parent application. The description may not include matter that was not originally disclosed in the parent application. Generally, the body of the specification of the divisional application is the same as that of the parent application and the claims of the divisional application are usually a subset of the claims of the parent application and may not go beyond the original disclosure.

Acceptance of a South African patent application generally takes place 12 months from the filing of a South African national phase application (or 18 months from filing a South African complete application). One must keep in mind that even once acceptance of an application has been received from the South African Patent Office it can be withdrawn and delayed for a period of time, in order to allow the applicant to consider possible amendments and the filing of a divisional application.

Our law does not specifically exclude double-patenting, but the intention of our legislation is to divide out part of the claims of the parent application by deleting these from the parent application and including them in the divisional application. However, South Africa is not an examining country and double patenting may thus occur when the claim set which is divided out, is not deleted from the parent application.

The filing of divisional patent application can therefore open up more options for patent strategy, in order to pursue patent protection in a more targeted and comprehensive manner. In order to obtain a higher degree of protection, the applicant must have a clear understanding of the optimal timeframe for filing a divisional application and filing claim amendments to the parent application.

Originally published July 2016

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.