Physicality in Australian patent law

It is generally understood that the patent system exists to encourage the conception and disclosure of new and useful inventions embodied in machines and other physical devices, along with new methods that physically transform matter from one state to another. What is not well understood is whether, and to what extent, the patent system is to encourage and protect the conception and disclosure of inventions that are non-physical methods – namely those that do not result in a physical transformation of matter. This issue was considered in Grant v Commissioner of Patents. In that case the Full Court of the Federal Court of Australia held that an invention must involve a physical effect or transformation to be patentable subject matter. In doing so, it introduced a physicality requirement into Australian law. What this article seeks to establish is whether the court’s decision is consistent with the case law on point. It does so by examining the key common law cases that followed the High Court’s watershed decision in National Research Development Corporation v Commissioner of Patents, the undisputed authoritative statement of principle in regard to the patentable subject matter standard in Australia. This is done with a view to determining whether there is anything in those cases that supports the view that the Australian patentable subject matter test contains a physicality requirement

Decision Problems For Turing Machines

We answer two questions posed by Castro and Cucker, giving the exact complexities of two decision problems about cardinalities of omega-languages of Turing machines. Firstly, it is $D_2(\Sigma_1^1)$-complete to determine whether the omega-language of a given Turing machine is countably infinite, where $D_2(\Sigma_1^1)$ is the class of 2-differences of $\Sigma_1^1$-sets. Secondly, it is $\Sigma_1^1$-complete to determine whether the omega-language of a given Turing machine is uncountable.Comment: To appear in Information Processing Letter