Merck Sharpe Dohme Group and Merial LLC v Cipla Agrimed (Pty) Ltd

Merck Sharpe Dohme Group and Merial LLC were the joint patentees of South African Patent No 1998/10975, relating to a long-acting injectable veterinary formulation using specific combinations of hydrophobic carriers to achieve prolonged antiparasitic activity. Cipla Agrimed (Pty) Ltd applied to the Commissioner of Patents for revocation of the patent on the ground of lack of novelty, relying on the patentees’ own earlier South African Patent No 92/7457 as prior art. The Commissioner of Patents held that the later patent was anticipated by the earlier patent and revoked it. Merck and Merial appealed to the Supreme Court of Appeal.

The appeal was upheld with costs. The order of the Commissioner of Patents was set aside and replaced with an order dismissing the application for revocation. All claims of South African Patent No 1998/10975 were certified as valid in terms of section 74 of the Patents Act 57 of 1978, with costs awarded to the joint patentees.

The case is a leading South African authority on anticipation and novelty in patent law. It firmly adopts the two-step test of disclosure and enablement for anticipation, aligns South African law with modern UK and international jurisprudence, and clarifies that generalized prior disclosures do not necessarily anticipate specific later claims. It also confirms that selection patents are not subject to special rules but are assessed under ordinary principles of novelty.