How should patent examiners approach double inclusion in claims?

Patent examiners should approach double inclusion in claims with careful consideration of the specific context and claim language. The MPEP 2173.05(o) provides guidance for examiners:

“The facts in each case must be evaluated to determine whether or not the multiple inclusion of one or more elements in a claim gives rise to indefiniteness in that claim.”

The MPEP also advises caution when applying older cases:

“Older cases, such as Ex parte White, 127 USPQ 261 (Bd. App. 1958) and Ex parte Clark, 174 USPQ 40 (Bd. App. 1971) should be applied with care, according to the facts of each case.”

Examiners should:

• Evaluate each instance of double inclusion on its own merits
• Consider whether the double inclusion creates ambiguity or indefiniteness in the claim’s scope
• Be aware that double inclusion is generally less problematic in Markush groups
• Pay special attention to device claims where double inclusion might lead to indefiniteness
• Apply older case law carefully, considering the specific facts of each case

To learn more:

• patent examination
• double inclusion
• claim indefiniteness
• MPEP guidance
• claim interpretation