How can an applicant resolve ambiguities in functional limitations?

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.

The MPEP provides several ways an applicant can resolve ambiguities in functional limitations during prosecution:

1. Use a quantitative metric instead of a qualitative functional feature. For example, include a numeric limitation for a physical property.
2. Demonstrate that the specification provides a formula for calculating a property, along with examples that meet and do not meet the claim limitation.
3. Show that the specification offers a general guideline and sufficient examples to teach a person skilled in the art when the claim limitation is satisfied.
4. Amend the claims to recite the particular structure that accomplishes the function.

As stated in the MPEP, “During prosecution, applicant may resolve the ambiguities of a functional limitation in a number of ways.” The goal is to provide clarity and definiteness to the claim language while maintaining the intended scope of the invention.