Comprising is Not a Weasel Word

The term “comprising,” when used in the preamble of a claim, permits the inclusion of other elements or materials in addition to those specified in the claim. However, “‘comprising’ is not a weasel word with which to abrogate claim limitations.” Dippin’ Dots, Inc. v. Mosey, 476 F.3d 1337, 1343 (Fed.Cir.2007).

Ex parte Martino involved a claim that required “[a] hand held olfactory tester comprising … a single odorant chamber.” Decision on Appeal, Appeal No. 2020-001003, at 2 (P.T.A.B. Sept. 11, 2020) (non-precedential).

In rejecting the claim, the Examiner only presented prior art having a tester with a plurality of chambers. Yet, the Examiner argued that the claim was obvious because “the plurality of containers shown [in the prior art] also include a single container.” Id. at 6. According to the Examiner, the claims needed to recite that the tester consists of only a single chamber because the term “comprising” allowed for additional, unrecited elements.

The Applicant disagreed, because the claim explicitly required a single chamber. The Board sided with the Applicant.

The Board noted that “[t]he presumption raised by the term ‘comprising’ does not reach into each of the [elements] to render every word and phrase therein open-ended,” and must be read in view of the specification. Id. at 4. The Board then applied a two-step analysis. First, the Board found that the ordinary and customary meaning of the term “single” is “one and only one.” Next, the Board confirmed that the specification was consistent with this meaning. Here, the Board highlighted, among other things, that the specification differentiated prior art testers having a number of odorant chambers, described a housing  with “an odorant chamber,” and depicted a device with only one chamber. Consequently, the Board found that the term “comprising” in the preamble did not negate the meaning of “single” as understood by one in the art.

Without any prior art disclosing or otherwise suggesting a tester comprising a single chamber, the Board reversed the Examiner’s obviousness rejection.

Takeaway: The scenario in Martino is quite common because of the presumption to construe the term “comprising” to be nonexclusive and the tendency for some examiners to play wordsmith. Martino also shows that even when there is no ambiguity in the claim language, the Board may still consult the specification for consistency with the ordinary and customary meaning of a term like “single.” So, what other options are available if you want to claim a limited number (e.g., one) of an element but the specification permits a plurality? One option is to add a wherein clause that states, “wherein the [device, article, composition, etc.] comprises no more than one element.”

Judges: A. Fetting, U. Jenks, A. Shah