Co-inventor

In patent law, an inventor is the person, or persons in United States patent law, who contribute to the claims of a patentable invention. In some patent law frameworks, however, such as in the European Patent Convention (EPC) and its case law, no explicit, accurate definition of who exactly is an inventor is provided. The definition may slightly vary from one European country to another. Inventorship is generally not considered to be a patentability criterion under European patent law.

Under U.S. case law, an inventor is the one with "intellectual domination" over the inventive process, and not merely one who assists in its reduction to practice. Since inventorship relates to the claims in a patent application, knowing who an inventor is under the patent law is sometimes difficult. In fact, inventorship can change during the prosecution of a patent application as claims are deleted or amended.

"Joint inventors", or "co-inventors", exist when a patentable invention is the result of inventive work of more than one inventor. Joint inventors exist even where one inventor contributed a majority of the work.

Absent a contract or license, the inventors are individuals who own the rights in an issued patent. Status as an inventor dramatically alters parties' ability to capitalize on the invention.

Under the European Patent Convention (EPC), identifying the inventor of a given invention is theoretically very important since "[t]he right to a European patent (...) belong[s] to the inventor or his successor in title", according to the first-to-file principle. In practice however, the European Patent Office (EPO) never investigates whether the proposed inventor is indeed the true inventor. Indeed, "[f]or the purposes of proceedings before the [EPO], the applicant shall be deemed to be entitled to exercise the right to the European patent".

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Wikipedia