Patent eligibility

Patentable, statutory or patent-eligible subject matter is subject matter which is susceptible of patent protection. The laws or patent practices of many countries provide that certain subject-matter is excluded from patentability, even if the invention is novel and non-obvious. Together with novelty, inventive step or nonobviousness, utility, and industrial applicability, the question of whether a particular subject matter is patentable is one of the substantive requirements for patentability.

The subject-matter which is regarded as patentable as a matter of policy, and correspondingly the subject-matter which is excluded from patentability as a matter of policy, depends on the national legislation or international treaty.

According to the Canadian Intellectual Property Office (CIPO) patents may only be granted for physical embodiments of an idea, or a process that results in something that is tangible or can be sold. This excludes theorems and computer programs per se. However, business methods are patentable.

The European Patent Convention does not provide any positive guidance on what should be considered an invention for the purposes of patent law. However, it provides in Article 52(2) EPC a non-exhaustive list of what are not to be regarded as inventions, and therefore not patentable subject matter:

The following in particular shall not be regarded as inventions within the meaning of paragraph 1:

Article 52(3) EPC then qualifies Art. 52(2) EPC by stating:

The provisions of paragraph 2 shall exclude patentability of the subject-matter or activities referred to in that provision only to the extent to which a European patent application or European patent relates to such subject-matter or activities as such.

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Wikipedia