先せん発はつ明めい主しゅ義ぎ

noun

first-to-invent principle; first-to-invent system

A patent law principle where the patent is granted to the person who can prove they were the first to invent, regardless of filing date. Contrasted with 先願主義 (first-to-file).

See also: 先願主義

• アメリカは長なが年ねん、先せん発はつ明めい主しゅ義ぎを採さい用ようしていた。

  The United States long adhered to the first-to-invent system.