X v Canada is an important Canadian patent

Patent

A patent is a form of intellectual property. It consists of a set of exclusive rights granted by a sovereign state to an inventor or their assignee for a limited period of time in exchange for the public disclosure of an invention....

law case concerning the requirement that inventions must be useful to be patented.

Background

The alleged invention in this case is called a "Death Ray". The patent claims, essentially, a device that creates a path of ionized air using a lazer beam to transmit electrical energy without wires. The invention had not actually been constructed by the inventor because of the significant cost of doing so. The Commissioner of Patents refused the patent application as "inoperable for the purpose for which it was designed."

Decision of the Court

Justice Thurlow dismissed the inventor's appeal and affirmed the decision of the Commissioner of Patents. The patent did not disclose how a technical challenge would be addressed and was not written clearly enough to enable a person skilled in the art to make or use the invention. The judge also conluded that comments in the Commissioner's decision concerning the absence of a working model of the invention and describing the invention as an abstract theorem were obiter and were not relevent to the application's refusal. As a result, the appeal was dismissed.