What is a count in patent interference proceedings?

This page is an FAQ based on guidance from the Manual of Patent Examining Procedure. It is provided as guidance, with links to the ground truth sources. This is information only: it is not legal advice.

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.