Walker v Alemite Corporation

The appellants, Henry Montague Walker and Daisy Jeannette Walker, trading as the Rox Manufacturing Company, appealed from a decision of the Supreme Court of Victoria. The respondent, Alemite Corporation, had brought an action alleging that the appellants had infringed its letters patent for improvements in lubricating apparatus by manufacturing and selling grease-cups or nipples. The respondent sought an injunction and damages.

The legal issues before the High Court were whether the appellants' grease-cups constituted an infringement of the respondent's patent, and whether the patent was valid. Specifically, the court had to determine if the appellants' device was a mere mechanical equivalent or a colourable imitation of the patented article, and whether a patent for a combination of parts was infringed by the manufacture or sale of individual components of that combination. The appellants also contended that the patent was invalid due to lack of novelty and that their device did not infringe the specific claims made in the respondent's patent specification.

The Court found that the respondent's patent claimed a specific construction for a grease-cup, which included a pin extending from and through the walls of the hollow member and projecting outwardly therefrom, serving to retain a spring. The appellants' device, however, substituted a collar around the hollow member with outwardly projecting pins or lugs to form a bayonet coupling, and the spring was confined between the closure member and the walls and end of the cylinder. The Court held that this difference meant the appellants' device was not a mere mechanical equivalent or a colourable imitation of the patented article, as the specific construction of the pin was an essential feature of the respondent's claim. Furthermore, the Court affirmed the legal principle that a patent for a combination of various parts is not infringed by the manufacture or sale of the separate parts.

Consequently, the High Court allowed the appeal, reversing the decision of the Supreme Court of Victoria. The Court concluded that the appellants' grease-cups did not infringe the respondent's patent, and that the respondent's patent was not infringed by the manufacture or sale of individual components of the claimed combination.