Interference proceeding

An interference proceeding, also known as a priority contest, is an inter partes proceeding to determine the priority issues of multiple patent applications. Until the Leahy-Smith America Invents Act of 2011, it was a unique procedure in the patent law of the United States. Unlike in most other countries which had a first-to-file system, the former first-to-invent system of the U.S. allowed a party which has failed to file a patent application on time to challenge the inventorship of another party which had a granted or pending patent, if certain requirements were met.

An interference proceeding is an administrative proceeding conducted by a panel of administrative patent judges (administrative law judges sitting on the Board of Patent Appeals and Interferences) of the United States Patent and Trademark Office (USPTO) to determine which applicant is not entitled to the patent if both claimed the same invention in:

A panel, composed of judges on the Board of Patent Appeals and Interferences, a quasi-judicial body in the USPTO, hears an interference contest. Its final judgment adjudicating one party as an earlier inventor is called a priority award, or simply an award. Appeals from this tribunal are heard before either the United States Court of Appeals for the Federal Circuit or the United States District Court for the District of Columbia. See 35 U.S.C. § 144, 35 U.S.C. § 146.

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