WM Wrigley Jr Co v Cadbury Schweppes Pty Ltd

In the matter of WM Wrigley Jr Co v Cadbury Schweppes Pty Ltd, the Federal Court of Australia was tasked with determining whether certain aspects of the invention claimed by the patent holder were part of the common general knowledge at the priority date. The dispute centred on whether the patent holder's claims regarding the sugarless hard coating for chewing gum were truly novel and inventive, or if they were already known within the relevant field. The case hinged on the interpretation of the "Background of the Invention" section of the patent specification and whether it accurately reflected the common general knowledge at the time.

The court was required to decide if the patent holder had accurately represented the state of the art as it existed at the priority date. This involved scrutinising the patent specification to determine if the claimed aspects of the invention were indeed novel and inventive, or if they were already known and therefore part of the common general knowledge. The court also had to consider whether the patent holder's assertions about the deficiencies and limitations of sorbitol coatings were supported by the evidence presented.

The court found that the patent holder had acknowledged certain aspects of the invention to be part of the common general knowledge by explicitly stating them in the "Background of the Invention" section of the patent specification. This section, by its very nature, sets out what is already known and commonplace in the field, thus any information included within it can be taken as an admission of its status as common general knowledge. The court concluded that the patent holder's claims regarding the use of sorbitol and other sugarless sweeteners, as well as the known limitations and market needs, were part of the common general knowledge at the priority date.

As a result, the court ruled that the patent holder's claims did not meet the threshold requirement of inventiveness, as they did not sufficiently depart from what was already known. The court's decision was based on the premise that the patent holder's own specification indicated that the claimed aspects were part of the common general knowledge. Consequently, the patent was found to be invalid on the grounds of lack of inventiveness. The court directed the parties to bring in minutes of proposed orders to give effect to these reasons and adjourned the hearing to a later date.