What is a count in patent interference proceedings?

A count in patent interference proceedings is a description of the interfering subject matter. As stated in the MPEP 2304.02(b):

“A count is just a description of the interfering subject matter, which the Board uses to determine what evidence may be used to prove priority under pre-AIA 35 U.S.C. 102(g)(1).”

In other words, the count serves as a basis for determining which party has priority in inventing the disputed subject matter.

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Topics: MPEP 2300 - Interference And Derivation Proceedings, MPEP 2304.02(B) - Counts And Corresponding Claims, Patent Law, Patent Procedure
Tags: Count, Interfering Subject Matter, Patent Interference