Sandvik Intellectual Property AB v Outokumpu OYJ and Another

The case concerned an application by Sandvik Intellectual Property AB to revoke South African Patent No. 2002/5826 (also referred to as 2002/58267), entitled ‘Belt for the thermal treatment of a continuously operated material bed’, which related to a metal conveyor belt used in a sintering process. The patent originated from a Finnish priority application and entered South Africa via the PCT national phase. The claimed invention focused on a perforated metal conveyor belt with perforations arranged in alternating zones and comprising 20–60% of the belt area. Sandvik sought revocation on several grounds under s 25 of the Patents Act 57 of 1978, including lack of novelty, lack of clarity, lack of fair basis, and lack of inventive step. By the time of appeal, only the alleged lack of an inventive step remained in dispute. The Commissioner of Patents dismissed the revocation application and certified the patent as valid. Sandvik appealed to the Supreme Court of Appeal.

The appeal was upheld with costs. The judgment of the Commissioner of Patents was set aside and substituted with an order revoking South African Patent No. 2002/5826 and awarding Sandvik the costs of the revocation application, including costs related to the joinder of the second respondent.

The decision reaffirms the South African approach to obviousness in patent law and underscores that an alleged inventive step must reflect a genuine technical advance over the prior art. It confirms that broad numerical ranges, without a demonstrated technical effect or advantage reflected in the claims, are unlikely to confer inventiveness. The case also illustrates the strict focus on the claims themselves, rather than advantages described only in the body of the specification, when assessing patent validity.