What is the relationship between functional language and 35 U.S.C. 112(f)?

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 relationship between functional language and 35 U.S.C. 112(f) is crucial in patent claim interpretation. Key aspects include:

• 35 U.S.C. 112(f) allows for functional claiming in combination with means-plus-function or step-plus-function language
• It provides a way to use functional language without running afoul of indefiniteness concerns
• Claims using 112(f) are interpreted to cover the corresponding structure, material, or acts described in the specification

MPEP 2173.05(g) states: “Unlimited functional claim limitations that extend to all means or methods of resolving a problem may not be adequately supported by the written description or may not be commensurate in scope with the enabling disclosure, both of which are required by 35 U.S.C. 112(a) and pre-AIA 35 U.S.C. 112, first paragraph.” This highlights the importance of proper support in the specification when using functional language, especially in the context of 112(f).