What are the guidelines for using narrow and broader ranges in the same patent claim?

Using narrow and broader ranges in the same patent claim can be problematic and may lead to indefiniteness. The MPEP provides the following guidelines:

• Examples and preferences should be set forth in the specification rather than in a single claim.
• A narrower range or preferred embodiment may be set forth in another independent claim or in a dependent claim.
• If stated in a single claim, examples and preferences can lead to confusion over the intended scope of the claim.

As stated in MPEP 2173.05(c): “In those instances where it is not clear whether the claimed narrower range is a limitation, a rejection under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph should be made.”

However, it’s important to note that: “While a single claim that includes both a broad and a narrower range may be indefinite, it is not improper under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C.112, second paragraph, to present a dependent claim that sets forth a narrower range for an element than the range set forth in the claim from which it depends.”

To learn more:

• narrow ranges
• broad ranges
• patent claims
• indefiniteness
• dependent claims