There has been much written on use of functional language in patent claims, such as terms like “configured to” or “adapted to” or “so that” or “causing”. Is it intended use? Is it “merely” functional language? Does it connote a structural relationship? Is it a conditional limitation? You can find yourself mired in all of these issues when using such language. Nevertheless, some examiners might actually prefer some “configured to” language and view it favorably and a helpful way to distinguish cited art.

MPEP 2173.05(g) discusses functional language, and explains that a claim term is functional when it recites a feature “by what it does rather than by what it is.” Further, this section of the MPEP confirms that there is nothing inherently wrong with defining some part of an invention in functional terms.

Next, MPEP 2114 explains that with regard to apparatus and article claims, functional language does not enable novelty by itself. Specifically, this section explains that "while features of an apparatus may be recited either structurally or functionally, claims directed to an apparatus must be distinguished from the prior art in terms of structure rather than function." Intended use also rears its ugly head here as the section goes on to state that:

A claim containing a “recitation with respect to the manner in which a claimed apparatus is intended to be employed does not differentiate the claimed apparatus from a prior art apparatus” if the prior art apparatus teaches all the structural limitations of the claim.

So we have the notion that one cannot ignore claim limitations, yet not all limitations are given patentable weight, and it sometimes depends on whether we are dealing with anticipation or obviousness. Plus we have Section 112(f) and MPEP 2181, which is a whole other can of worms that can further complicate the situation.

If you are confused, then that is a good sign because much of the end result appears to be very fact specific and subject to persuasive arguments. The point here is that if are are dealing with these issues, know that the outcome is not predetermined and there are ways to successfully navigate rejections that ignore claimed elements, even when written as what some might call mere functional language.

Case in point: 15/299,952. An ex parte PTAB appeal by Black and Decker for a portable battery pack that disconnects cells to reduce current leakage. As noted above, we all know that if the only difference from the prior art is that of function, things are looking bad for the patent applicant. Specifically, once this occurs, there is burden shifting that occurs where the Office establishes a reason to believe that functional limitation is inherent in the prior art. See In re Schreiber, 128 F.3d 1473, 1478 (Fed. Cir. 1997); MPEP 2114(I).

Often at the board, the benefit of the doubt seems to go to the examiner in this regard. But, as noted above, all is not lost where the applicant can clearly show, with evidence of record, that the prior art structure inherently does not perform the function. In the Black and Decker case, the limitation at issue related to a “mechanical coupler for causing a switching network to convert from a first state (with cells connected) to a second status (with cells disconnected). The examiner was relying on a physical wall in the prior art, which if removed, would allow for cell connection. You have to give it to the examiner for being creative in the rejection. Black and Decker argued, as one would expect, that the wall in the cited art does not cause anything to happen.

Here, the PTAB provides a roadmap for arguing persuasively that the so-called “functional” limitation is not inherently present in the allegedly anticipatory reference. Specifically, the PTAB explain how, due to the particular structure in the cited reference, it cannot inherently possess the function ascribed to it by the Examiner. In this way, the burden never should have shifted to the applicant since that occurs only where the Office establishes a reason to believe the the functional limitations is an inherent characteristic of the cited art.

The issue was so clear in this case that the PTAB cancelled oral argument as unnecessary and reversed the rejections.

So, while in some cases it might be possible to show that a “configured to” feature is actually structural (e.g., by describing a structural relationship between various components), even when pigeonholed into mere functional language, all is not lost.