Patent Scope Unable to be ‘Re-Cooked’
Patentee's infringement claim barred by words of their own choosing...
In Doug Andrews Heating and Ventilation Ltd v Dil the Court of Appeal upheld the High Court finding that Doug Andrews patent for a portable hangi cooker was not infringed by Dil’s UFO cooker.
Doug Andrews patent is in relation to a portable multi-level cooker comprised of inter-engaging parts. The lower part houses the heating means below a chamber that holds liquid for steaming, or smoking essences, but is not adapted for cooking food within. The upper part houses containers in which the food is to be cooked.
Dil’s UFO cooker can either be used as a single piece, as the chamber above the heating means can be used to cook food, or be comprised of an additional food cooking part that inter-engages with and above the first part.
In construing their primary claim Doug Andrews argued that it is infringed by a two-tier structure that inter-engages to form a cooking chamber, and used this to claim that the UFO cooker infringed when comprised of the additional food cooking layer.
The Court of Appeal concurred with the High Court Judge’s rejection of that argument. When properly construed claim one was found to extend protection to hangi cookers in which only the second part comprises a cooking chamber. Consequently, the UFO cooker does not infringe, since the first part contains a cooking chamber and the second part merely extends that. The Court of Appeal noted that the inventive contribution of Doug Andrews cooker may have been drafted so as to also cover the UFO cooker, but that by not so marking out their monopoly they cannot now seek to reclaim it.
The Court of Appeal also rejected Dil’s cross-appeal for invalidity on the basis of prior use and obviousness. The evidence of prior use was either unreliable or even contrived. Regarding obviousness, the Court of Appeal held that Dil had not discharged their onus of establishing what was used in a public manner before the priority date, what was common general knowledge and what were the attributes of the skilled addressee. The Court of Appeal also found that the Judge had correctly treated the commercial success of Doug Andrews multi-level cooker as a secondary consideration in establishing inventiveness.