What is a single means claim, and how do we properly draft claims so as to not run afoul of a single means claim rejection?  According to the MPEP (Manual of Patent Examining Procedure) 2164.08(a), “A single means claim, i.e., where a means recitation does not appear in combination with another recited element of means, is subject to an undue breadth rejection under 35 U.S.C. 112, first paragraph.  In re Hyatt, 708 F.2d 712,714-715, 218 USPQ 195, 197 (Fed. Cir. 1983)”.  Taken narrowly, the above guidance instructs us to not write claims of the format:

1.  A widget comprising:
            means for performing function X.      (Or, just means for X)

Means plus function claiming has fallen out of favor these days, so it would seem at first glance the easiest way to avoid drafting a single means claim is to not write any claims with the phrase “means for” in them.  Yet, function-like language is often used in structural claims, and examiners (and courts) sometimes construe claim language as a means plus function claiming even when “means for” is not literally present in the claim.  Under such circumstances, an examiner can still reject the claim as allegedly being a single means claim.

A second look at the above guidance informs us that claims of the following format would be directed to a means recitation in combination with another recited element of means, and would thus not be a single means claim:

1.  A widget, comprising:
            means for X; and
            means for Y.

Further guidance is provided by MPEP 2181 V., which interprets In re Donaldson Co., 16 F.3d 1189, 29 USPQ2d 1845 (Fed. Cir. 1994): “As Donaldson applies only to an interpretation of a limitation drafted to correspond to 35 U.S.C. 112, sixth paragraph, which by its terms is limited to ‘an element in a claim to a combination,’ it does not affect a limitation in a claim which is not directed to a combination.  See also MPEP § 2164.08(a).”  Here, we see that a claim to a combination can have means language, and not be interpreted as a single means claim.  So, a claim of the following format is not a single means claim:

1.  A widget comprising:
            an element; and
            means for X.

From the above, we infer that claims to a combination of elements, even if one of the elements has functional language, possibly including a “means for” recitation, are not single means claims.  But what about a claim with a single element, for example a processor?  In re Hyatt refers to such a situation, where a “Fourier transform processor” performs a function, and the claim was held to be a single means claim.  Well, we could recite more than one function (or step, act or action) as follows:

1.  A widget comprising:
            an element configured to:
                        perform X;
                        calculate Y; and
                        do Z.

The above is roughly equivalent to claiming a combination of means for X; means for Y; and means for Z, narrowed by the recitation of a specific element (not literally the phrase “an element”).  For these reasons, a claim of this format is not a single means claim, it is a claim to a combination.  This is part of the art of patenting.  Oh, and Happy Holidays to all!