Patents protect new inventions, such as new or improved materials, products or processes. In order to be patentable, an invention must be novel, useful, and not obvious to a person skilled in the field of the invention.

Products, processes, machines,manufactures or composition of matter, or any new and useful improvement of any of these, such as new uses of known compounds, are patentable subject matter. Novel genetically engineered life forms and new microbial life forms can be patented in some jurisdictions, such as the United States, but not in others. (The Canadian position is still unclear.) Methods of medical treatment are also patentable in some jurisdictions, such as the United States, but not in others, including Canada.

Scientific theorems or principles, mere ideas, methods of doing business or of playing games, as well as anything that is illegal or illicit, are not patentable. Patent rights do not arise automatically. Rather in exchange for complete disclosure of an invention, the national government grants the patent owner the exclusive right to make, use or sell the invention for a limited period of time. Patents generally have a life of 17 to 20 years depending on the jurisdiction. In Canada, patent rights last 20 years from the date the patent application was filed.