Radiation Ltd v Galliers & Klaerr Pty Ltd

Radiation Ltd and another (the appellants) appealed to the High Court of Australia from a judgment of the Supreme Court of Victoria that dismissed their action against Galliers & Klaerr Pty Ltd (the respondent) for infringement of a patent. The patent related to improvements in gas-heated cooking apparatus, specifically concerning the arrangement of a flue outlet at the lower end of an oven. The primary defences raised by the respondent were that no infringement had occurred based on a proper construction of the patent claims, and alternatively, that the claims were void for ambiguity if construed broadly enough to encompass the alleged infringement.

The legal issues before the High Court were whether the respondent's gas stove infringed the appellants' patent, and whether the patent claims were valid and sufficiently clear to support an infringement finding. Specifically, the court had to determine the scope of the patent claim, particularly in light of the phrase "substantially as described," and whether the respondent's construction, which involved a rear burner and a rear chamber attached to the back of the oven, constituted an infringement of the patent's claim for a partition between a rear burner and a rear flue outlet.

The High Court, allowing the appeal, held that the patent claim was not ambiguous and that the respondent had infringed the patent. The court reasoned that the substance of the invention lay in the interposition of a partition between a rear burner and a rear flue outlet to facilitate the passage of gaseous products without interfering with combustion or circulation. While the respondent's stove differed in construction by attaching a separate chamber rather than forming a recess within the oven, the court found that this difference was merely one of workshop design and did not alter the essential function or substance of the patented invention. The court emphasised that the claim was limited to apparatus of the kind specified (flue outlet at the lower end of the oven) and that the respondent's stove met these criteria, with its rear wall acting as a partition separating the burner from the flue outlet.

The High Court ordered that the appeal be allowed, the judgment of the Supreme Court of Victoria be set aside, and that an injunction be granted restraining further infringement by the respondent. The court also ordered the respondent to pay the costs of the appeal and the action in the Supreme Court, while reserving to the appellants liberty to apply for an order for delivery up of infringing articles.