Patent examiner

A patent examiner (or, historically, a patent clerk) is an employee, usually a civil servant with a scientific or engineering background, working at a patent office. Major employers of patent examiners are the European Patent Office (EPO), the United States Patent and Trademark Office (USPTO), the Japan Patent Office (JPO), and other patent offices around the world.

Patent examiners review patent applications to determine whether the invention(s) claimed in each of them should be granted a patent or whether the application should instead be refused. One of the most important tasks of a patent examiner is to review the disclosure in the application and to compare it to the prior art. This involves reading and understanding a patent application, searching the prior art (including prior patent applications and patents, scientific literature databases, etc.) to determine what contribution the invention makes over the prior art, and issuing office actions to explain to the applicants and their representatives (i.e., patent attorneys or agents) any objections that may exist against the grant of a patent. In other words, an examiner reviews a patent application substantively to determine whether it complies with the legal requirements for granting of a patent. A claimed invention must meet patentability requirements of novelty, inventive step or non-obviousness, industrial application (or utility) and sufficiency of disclosure.

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