What is a proper Markush group in patent claims?

What is a proper Markush group in patent claims?

A proper Markush group in patent claims is a closed group of alternatives. According to MPEP 2117, “A Markush claim contains an ‘improper Markush grouping’ if either: (1) the members of the Markush group do not share a ‘single structural similarity’ or (2) the members do not share a common use.” The MPEP further states:

“Treatment of claims reciting alternatives is not governed by the particular format used (e.g., alternatives may be set forth as ‘a material selected from the group consisting of A, B, and C’ or ‘wherein the material is A, B, or C’).”

In essence, a proper Markush group should have a common structural feature or a common use among its members. The specific format of the claim is less important than ensuring the group shares these commonalities.

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Topics: MPEP 2100 - Patentability, MPEP 2117 - Markush Claims, Patent Law, Patent Procedure
Tags: Alternative Limitations, markush claims, patent claims, Proper Markush Group