senior party
senior party. Intellectual property. In an interference proceeding, the first person to file an application for a property’s legal protection, e.g., an invention patent or a trademark registration. • In the United States, merely being the first to file does not entitle the party to the protection. The proceeding’s administrator also takes other factors into account. For instance, in a patent-interference proceeding the invention’s conception date and the inventor’s diligence in reducing the invention to practice are relevant factors. Priority in the filing date is prima facie evidence that the senior party is the first inventor, so the challenger has the burden of proof. Cf. JUNIOR PARTY. [Cases: Patents 106(1). C.J.S. Patents §§ 159–162, 165.]
