Federal Circuit Finds ‘Lifter Member’ Invokes Means-Plus-Function

“One lesson might be to just not use the term ‘member’ or, if one does, modify it with something structural.”

Federal CircuitOn January 21, 2022, the U.S. Court of Appeals for the Federal Circuit held that the term “lifter member” invokes means plus function (MPF) claiming. The case is Kyocera Senco Indus. Tools Inc. v. ITC, Appeal Nos. 2020-1046 and 2020-2050 (Fed. Cir. 2022). The Federal Circuit panel for the case consisted of Chief Judge Moore along with Judges Dyk and Cunningham. Chief Judge Moore wrote the opinion for the panel.

To summarize, in 2017, Kyocera filed a complaint with the International Trade Commission (ITC). Kyocera alleged that a company named Koki violated 19 U.S.C. § 1337 (Section 337) by importing gas spring nailer products that infringe, or were made using methods that infringe, certain claims in five Kyocera patents. Those patents generally relate to linear fastener driving tools, like portable tools that drive staples, nails, or other linearly-driven fasteners.

Based on Kyocera’s complaint, the ITC instituted an investigation to determine whether Koki was violating Section 337. After institution, Koki denied infringement and argued that the asserted claims were invalid. Ultimately, the ITC found that the accused product met certain limitations from the claims, and also found that Koki induced infringement. Both parties appealed.

Altogether, the Federal Circuit addressed five parts of the ITC’s investigation. Namely, the Federal Circuit addressed the exclusion of expert testimony, the construction of three different claim terms, and whether a certain reference teaches yet another claim term. Below we will highlight a few interesting aspects of the decision, but follow this link to the opinion if you want to read about all five issues.

i. Expert Testimony

In terms of expert testimony, the administrative law judge (ALJ) at the ITC adopted a certain definition of a skilled artisan that necessitated, at minimum, two years’ experience in designing power nailers. Though Kyocera did not contest this definition at the time it was adopted, Kyocera subsequently offered a technical expert on claim construction, invalidity, and infringement (both literally and under the doctrine of equivalents), but the expert did not have experience in power nailer design. The fact that he had advanced degrees in engineering and extensive experience in the design and manufacture of fastener driving tools was apparently of no moment – the ALJ ultimately excluded nearly all of the expert’s testimony save for on the issue of literal infringement. Kyocera then appealed to the Federal Circuit that all of the expert’s testimony should have been included, while naturally Koki argued that none of the expert’s testimony should have been included.

Under the abuse of discretion standard, the Federal Circuit ultimately held that the ALJ abused his discretion by allowing any of the expert’s testimony since the expert lacked the requisite skill in the art: “To offer expert testimony from the perspective of a skilled artisan in a patent case – like for claim construction, validity, or infringement – a witness must at least have ordinary skill in the art. Without that skill, the witness’ opinions are neither relevant nor reliable. The opinions would not be based on any specialized knowledge, training, or experience that would be helpful to the factfinder. In fact, ‘[a]dmitting testimony from a person…with no skill in the pertinent art serves only to cause mischief and confuse the factfinder.’…That testimony would ‘amount[] to nothing more than advocacy from the witness stand.’…This is true regardless of whether the witness is being offered to testify on literal infringement, doctrine-of-equivalents infringement, or both. Nothing about literal infringement makes an unqualified witness’ testimony more relevant or more reliable. And the same goes for infringement under the doctrine of equivalents. The absence of relevant knowledge and the risk for abuse apply equally to both situations [citations omitted].”

The Federal Circuit then discussed one of its prior decisions in AquaTex Industries, Inc. v. Techniche Solutions, 479 F.3d 1320 (Fed. Cir. 2007), noting that “[t]here, we addressed when expert testimony is required: always for doctrine-of-equivalents infringement and sometimes for literal infringement…We did not, however, address the minimum qualifications necessary to offer testimony from the perspective of a skilled artisan. Only the latter question is relevant here…To be sure, the person of ordinary skill in the art is a hypothetical construct. And as [Endress + Hauser, Inc. v. Hawk Measurement Systems Party, 122 F.3d 1040, 1042 (Fed. Cir. 1997)] recognized, it would be improper to require an expert witness to possess ordinary skill in the art and nothing more. If that were the case, ‘a person of exceptional skill in the art would be disqualified from testifying as an expert because [he is] not ordinary enough.’…But Endress itself recognized that, to testify as an expert, a witness must be qualified…And to be qualified to offer expert testimony on issues from the vantage point of an ordinarily skilled artisan in a patent case, an expert must at a minimum possess ordinary skill in the art [citations omitted, emphasis original].”

ii. Means Plus Function

Turning to another interesting issue addressed in Kyocera, the term “lifter member” as used in one of the asserted claims was held to invoke means plus function (MPF) claiming, with the Federal Circuit finding the ALJ erred in not applying §112 ¶ 6 but instead construing “lifter member” as a “rotatable component having lifting pins on its face surface.”

The claim at issue is long, so for brevity only the portion introducing the “lifter member” limitation is being reproduced here:

“a prime mover that moves a lifter member which moves a driver member away from an exit end of the mechanism”.

And to review, according to the Federal Circuit itself, “[u]nder the text of §112 ¶ 6, a patentee may draft claims ‘as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof.’ But such claims are construed to cover only ‘the structure, materials, or acts described in the specification as corresponding to the claimed function and equivalents thereof [citations omitted].’”

In the present instance, the Federal Circuit ruled de novo that the rebuttable presumption against construing claim terms as invoking MPF was overcome since “lifter member” itself did not connote sufficient structure. The Federal Circuit reasoned that “[a] person of ordinary skill in the art would not understand the claimed ‘lifter member’ to have ‘a sufficiently definite meaning as the name for a structure.’…That phrase, alone, does not connote structure. It is a non-structural generic placeholder (member) modified by functional language (lifter)…Indeed, no party claims lifter member has a plain and ordinary meaning to those skilled in the art…Likewise, the surrounding claim language does not describe any structural detail about the ‘lifter member’ [citations omitted].”

The Federal Circuit then went on to analyze the surrounding language of the relevant claim itself, indicating that “[t]his language requires the prime mover to move the lifter member and describes the lifter member’s function as lifting the driver member. It does not specify whether or how the prime mover is connected to the lifter member. Nor does the description of the lifter member’s function add any structural detail. The only thing a skilled artisan could glean from the claim language is that the lifter member is moved by the prime mover and lifts the driver member. That is a purely functional description.”

Two Takeaways

The Federal Circuit’s decision here leads to two observations. First, “member” may as well be considered a recitation of “means” because both Mas-Hamilton Grp. v. LaGard, Inc., 156 F.3d 1206 (Fed Cir. 1998), cited in Kyocera, and Kyocera itself said as much. In other words, the presumption against employing MPF in the absence of the word “means” does not mean much at all because it is easily overcome when one uses “member”, however modified with functional language.

So, one lesson might be to just not use the term “member” or, if one does, modify it with something structural. For instance, “reciprocating member” has been held to not invoke MPF. See CCS Fitness, Inc. v. Brunswick Corp., 288 F.3d 1359 (Fed. Cir. 2002), which, interestingly, was a decision in which the Federal Circuit explicitly indicated that “More important, ‘member,’ as defined by common and technical dictionaries, refers to a ‘structural unit such as a…beam or tie, or a combination of these,’ see McGrawHill Dictionary of Scientific and Technical Terms 1237 (5th ed.1994), or to a ‘distinct part of a whole,’ see American Heritage Dictionary 849 (3d ed.1996).” But this Federal Circuit inconsistency should not be a shock anyone who follows its abstract idea jurisprudence. I’m sure the facts were different in CCS Fitness.

In any case, continuing with the first observation, one might also simply omit as much generic element claiming as possible. Here “member” was used in the claim simply as a coupling between a prime mover and a driver member. The claim could have recited “coupling” or even “a prime mover coupled to the driver to move the driver”. Moreover, if patentability actually hung on there being a lifting member in the claim, something of that importance should have been called out in another claim in terms that were not so obviously generic, and much more structure than evidently existed should have been provided in the specification.

The second observation is to note that the Federal Circuit correctly identifies a statutory equivalent infringement theory that attaches to 112(f) or (6), namely, that MPF claims cover the structure, materials, or acts described in the specification “and equivalents thereof.” The difference between statutory equivalence and the Doctrine of Equivalents has been the subject of many articles, but it is important to remember that it exists when MPF is in play.


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Join the Discussion

One comment so far.

  • [Avatar for Anon]
    January 26, 2022 03:46 pm

    Here “member” was used in the claim simply as a coupling between a prime mover and a driver member.


    Under this logic, driver member would also be equated to be merely “member” and you would have a circular statement.

    Whatever logic you want to apply to lifter member, you need to also apply to driver member.