Groundprobe Pty Ltd and Another v Reutech Mining (Pty) Ltd and Others

The first appellant, Groundprobe Pty Ltd (an Australian company), was the proprietor of South African patent 2012/08400 entitled 'Work Area Monitor'. The second appellant, Groundprobe South Africa (Pty) Ltd, was a licensee under the patent. The appellants instituted a patent infringement action against the respondents (three related companies) alleging infringement by the respondents' manufacture, use and sale of mine slope monitoring systems (MSR 060V and MSR 120V) comprising a radar and interferometric processor mounted on a light delivery vehicle (bakkie). The third respondent admitted infringement of certain claims. The respondents counterclaimed for revocation of the patent on grounds including lack of inventive step. The patent related to a work area monitor using radar to detect slope movement in open cast mines, employing interferometry. Both parties' systems (SSR and MSR) existed before the priority date (16 August 2011) as trailer-mounted systems. The patented invention essentially involved mounting the known radar system on a motorised automobile vehicle instead of a trailer.

• Whether the patent involved an inventive step as required by section 25(1) of the Patents Act 57 of 1978
• Whether the invention was obvious to a person skilled in the art having regard to the state of the art at the priority date
• What constituted the inventive concept of the patent claims
• Whether mounting a known radar system on a motorised vehicle instead of a trailer was inventive
• Whether the stabilisation apparatus constituted an inventive step

The appeal was dismissed with costs, including costs of two counsel. The patent was revoked for lack of inventive step.

The mere mounting of a known radar system (previously mounted on a trailer) onto a motorised automobile vehicle does not involve an inventive step where: (i) the mounting of radar on motorised vehicles was known in analogous fields (such as military applications); (ii) there was cross-pollination of ideas between those fields and the relevant industry; (iii) no new stabilisation technology was required, with the same stabilisation apparatus being used on both mounting platforms; and (iv) the person skilled in the art (a mechanical engineer experienced in mounting and stabilising radar systems) would find the adaptation obvious. An invention lacks an inventive step, and is invalid for obviousness, where the ordinary person skilled in the relevant art, if faced with the problem solved by the invention and having regard to the state of the art at the priority date, could easily have provided the solution or taken the step taken by the patentee. The inventive step must be found in the claims of the patent, and where a patent discloses no advance in the underlying technology but merely a different mounting arrangement, the inventive concept (if any) must reside in that mounting arrangement alone.

The court quoted with approval Lord Herschell's century-old observation that "the mere adaptation to a new purpose of a known material or appliance, if that purpose be analogous so that no inventive faculty is required and no invention is displayed in the manner in which it is applied, is not the subject-matter for a patent." The court emphasised that the test for inventive step depends on expert evidence establishing the common general knowledge of the person skilled in the art and the teaching of the cited prior art. The court noted that patents should not be granted indiscriminately for so-called inventions where there exists a sufficiently strong probability that they are not really inventions at all, as these should not be allowed even temporarily to hamper the trade and industry of the country. The court observed that while it is appropriate to consider a combination as a whole rather than dissecting it into constituent elements, where stabilisation is a "physical fact" common to all such systems and no new stabilisation technology is involved, the stabilisation feature cannot constitute the inventive concept.

This case provides important guidance on the application of the inventive step requirement in South African patent law. It demonstrates that mere adaptation of known technology to a new but analogous purpose, without inventive ingenuity, does not satisfy the inventive step requirement under section 25(1) of the Patents Act 57 of 1978. The case illustrates the application of the structured Pozzoli/Windsurfing approach to assessing obviousness in South African patent law. It emphasises that the inventive concept must be identified from the claims themselves, and that where the only difference from prior art is a simple substitution or mounting variation of known technology, this will not constitute an inventive step. The judgment reinforces the public interest in not granting patents indiscriminately for non-inventive developments that would hamper trade and industry. The case also clarifies that the person skilled in the art must be identified according to the actual nature of the alleged advance, not merely the general field of technology.