Aktiebolaget Hässle and Another v Triomed (Pty) Ltd

The first appellant was the patentee of South African Patent No. 87/2378 relating to an oral pharmaceutical preparation containing omeprazole, and the second appellant was a licensee under the patent. The respondent imported and distributed a product known as Ulzec, alleged to infringe the patent. The appellants sought urgent interim relief before the Commissioner of Patents to restrain the respondent from distributing Ulzec pending an action for final relief. The Commissioner dismissed the application on the basis that Ulzec did not infringe the patent, finding that the patent claim required the subcoating layer to consist of more than one excipient or compound, whereas Ulzec used a single compound subcoating. The appellants appealed to the Supreme Court of Appeal, limited to the issue of infringement.

The appeal was upheld with costs. The order of the Commissioner of Patents was set aside. It was declared that the respondent, by importing, making, disposing of or offering to dispose of its Ulzec products, infringed claim 1 of Patent No. 87/2378. The application for a temporary interdict was remitted to the Commissioner of Patents for determination of the remaining issues.

The case is a leading South African authority on purposive construction of patent claims and the assessment of patent infringement. It reaffirms that courts must look beyond a purely literal reading of claim language to identify the essential features of an invention, and that minor or immaterial variations will not avoid infringement if the substance of the invention is taken.