Can a party lose on one issue but not on another in a patent interference?

Yes, it is possible for a party to lose on one issue but not on another in a patent interference proceeding. The MPEP 2308.03(a) clearly states:

“A party may lose on one issue, yet not lose on a different issue.”

This means that the outcome of an interference can be nuanced, with different determinations made for different aspects of the invention or claims in question. Each issue is considered separately, and a party’s success or failure on one issue does not necessarily dictate the outcome of other issues in the same proceeding.

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Topics: MPEP 2300 - Interference And Derivation Proceedings, MPEP 2308.03(A) - Losing Party, Patent Law, Patent Procedure
Tags: Partial Loss, patent claims, Patent Interference, USPTO procedures