Posts Tagged: "means-plus-function"

Inventors and practitioners alike are continually trying to push the bounds of protection on innovations. Whether it’s describing a telegraph as a means for communication or a lightbulb as a means for lighting an environment, using broad language, like “means for” language, to cover all the possible workarounds might seem more advantageous than disadvantageous, at first glance. In patent law, this broad language or “means for” phraseology is called functional language because it describes the device or system in terms of what it accomplishes rather than the actual structure. However, using functional language has lost favor over time. For example, a blog published by Patently-O in 2011 shows that the use of “means for” language has dropped precipitously from about 1990 to present day. What has turned this seemingly advantageous practice into a disadvantageous one?In this episode of Patently Strategic, the panel walks through several court cases that either: invalidated a patent for failing to define structures in the specification for the all the means-plus-function claim terms or maintained validity of the patent because the specification provided sufficient structure for all the means-plus-function claim terms.

Last week, the U.S. Court of Appeals for the Federal Circuit (CAFC) reversed and remanded a decision by the U.S. District Court for the Western District of Texas that Dyfan, LLC’s claims were invalid as indefinite. The CAFC concluded that the disputed claim limitations were not drafted in means-plus-function format, and therefore 35 U.S.C. § 112 ¶ 6 did not apply. Patent owner Dyfan sued Target Corp. for infringement of various claims of U.S. Patent Nos. 9,973,899 and 10,194,292. Following a claim construction hearing, the district court found that the disputed (1) “code”/“application” limitations and (2) “system” limitations of the patents-in-suit were invalid as indefinite. Specifically, the district court found that: (1) these claim limitations of the patents-in-suit are in means-plus-function format under Section 112 ¶ 6 and (2) the specification does not disclose sufficient structure corresponding to the recited functions. Dyfan subsequently appealed.

On 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.

In claim construction analyses, the plain and ordinary meaning of a claim term will not be narrowed by statements in the prosecution history, unless those statements clearly and explicitly evidence the patentee’s intent to depart from the full scope of the claim. If a dependent claim includes the purportedly disclaimed subject matter and was added at the time of the purportedly disavowing statements, a finding of disavowal is unlikely. Furthermore, a means-plus-function term should clearly and objectively define the function of the limitation; if the function is a subjective term of degree, a finding that the term is indefinite is likely.

On appeal to the Federal Circuit, Zeroclick argued that the district court erred in construing those two terms as means-plus-function limitations, an argument with which the Federal Circuit panel agreed. “Neither of the limitations at issue uses the word ‘means,’” Circuit Judge Hughes writes in his majority opinion. “Presumptively, therefore, [Section 112(f)] does not apply to the limitations.” Although Apple argued in the district court that the claims must be construed under Section 112(f), it provided no evidentiary support for its position. Although the court compared Apple’s arguments to Zeroclick’s objections, Judge Tigar did not point to any record evidence supporting the ultimate conclusion on Section 112(f) grounds.

Means plus function claiming allows the drafter to claim the invention based on functionality rather than the more traditional (and preferred) claiming technique that employs structure within the body of the claim itself… If there is no structure in the specification the person of skill in the art cannot save the disclosure by understanding what the drafter intended to be covered by the means plus function limitation in the claims. Thus, means-plus-function claims are valid at the mercy of the specification, and only to the extent that the specification contains support for the structures that define the means… The Federal Circuit does not blindly elevate form over substance when evaluating whether a particular claim limitation invokes means treatment. See Greenberg v. Ethicon Endo-Surgery, Inc., 91 F.3d 1580, 1584 (Fed. Cir. 1996) (“We do not mean to suggest that section 112(6) is triggered only if the claim uses the word ‘means.’”).

MindGeek and Playboy filed an IPR petition. The Board determined that § 112 ¶ 6 did not apply because “‘wireless device means’ is not purely functional language, but rather is language that denotes structure.” In the alternative, Skky argued that the “wireless device means” term should be construed to require multiple processors or a specialized processor. The Board found Skky’s alternative argument unconvincing. The claims were held invalid in light of prior art that disclosed a “wireless device means,” specifically a cell phone. Skky appealed.

The Court also affirmed that the this means-plus-function term was indefinite. In the case of computer-implemented functions, the specification must disclose an algorithm for performing the claimed function. The patents-in-suit did not disclose an operative algorithm for the claimed “symbol generator.” A patentee cannot claim a means for performing a specific function and then disclose a “general purpose computer” as the structure performing that function. The specification must disclose an algorithm in hardware or software for performing the stated function.

KAPPOS: “Back when I was an engineer we saw it in mainframe computers where you’d make an invention and frequently initially the software wasn’t fast enough to be able to run the algorithm. So the algorithm would first be built in silicon, really expensive, but you’d wind up then fabbing up chips to be special purpose chips to run the algorithm. And then later as the software got faster the underlying computer systems got faster you’d reimplement the same algorithm in software, same algorithm, same invention but just reimplement it in software and then even later after that when the ASIC density got good enough you’d reimplement yet again in an application-specific integrated circuit, an ASIC. And so you’d have a little bit of a hybrid, if you will, but more on the hardware side, it’s an IC. It’s again putting the algorithm in a chip. And so what you’d see by looking at that is that it made no sense to say that an algorithm was patentable if it was implemented in a hardware chip. But the same algorithm implemented in software was unpatentable. Just didn’t make sense to say that.”

In Williamson v. Citrix, the Federal Circuit overruled its own precedent that there is a “strong” presumption that claim limitations that do not use the term “means” are not means-plus-function limitations. This change has been decried by practitioners who purposefully avoid the word “means” in order to avoid means-plus-function treatment of their functionally claimed elements. Means-plus-function claiming is an opportunity to be embraced, not a trap to be avoided. Invoking §112(f) and the associated scope of a means-plus-function limitation is largely in the control of the patent drafter.

In general, the courts distinguish between functions and algorithms, and they require patent applicants to disclose algorithms to cure perceived deficiencies in functions. The problem with this line of reasoning is that both algorithms and functions under 35 U.S.C. § 112(f) are composed of the same things: steps. So the result of the algorithm requirement is to simply make patent applicants “fix” one step by specifying more steps. Accordingly, if the algorithm requirement is taken to its logical conclusion, then each step would be fixed with more steps, and each of those steps would be fixed with even more steps, like Russian dolls. Instead, the courts do not take the algorithm to its logical conclusion and, instead, only require a single layer: the original step and the further steps (i.e., algorithm) for it. This is arbitrary, confusing for patent applicants and examiners, and a poorly calibrated solution to concerns about software patents.

In this issue of the Federal Circuit Review: (1) A Patent Owner Must Show They Are Entitled to Amended Claims In an Inter Partes Review, Including in View Of All Prior Art of Record, and Known to the Patent Owner; (2) Federal Circuit Reverses Every E.D. Va. Claim Construction on Appeal in TomTom v. Adolph Mobile Tracking System Suit; and (3) Federal Circuit Overrule the “Strong Presumption” Embodied in § 112 para. 6 for Functional Limitations Expressed Without the Term “Means.”

The opinion focused on whether adequate structure corresponding to the “coordinating” function is disclosed in the specification. After determining that a special purpose computer is required to perform the function, the court searched for an algorithm for performing the function, but did not find one. The court rejected Williamson’s argument that the distributed learning control module controls communications among the various computer systems and that the “coordinating” function provides a presenter with streaming media selection functionality. The disclosures relied upon by Williamson were thought of by the court as merely functions of the distributed learning control module and opined that the specification does not set forth an algorithm for performing the claimed functions.

Functional claim language is increasingly being used by practitioners to capture the metes and bounds of an invention, especially in computer-implemented inventions. Sometimes using functional language in a claim limitation is unavoidable. Functional language does not, in and of itself, render a claim improper. However, as recently experienced in Williamson v. Citrix (en banc) and Robert Bosch, using functional language carries a significant risk of having the claim invalidated as indefinite following a determination that the claim invokes § 112(f) even when the patentee does not intend to have the claim treated under § 112(f).