Disclaimer in Prosecution cannot be Recaptured in Litigation

by Dennis Crouch

Traxcell Technologies, LLC v. Sprint Communications Company, No. 20-1440 (Fed. Cir. 2021); Traxcell Technologies, LLC v. Nokia Solutions and Networks, No 20-1440 (Fed. Cir. 2021)

The patentee primarily these cases on claim construction on two simple terms — based largely on statements made during prosecution to skirt the prior art. 

“Location” – some of the asserted claims take various actions related to the “location of [a] mobile wireless device.”  During prosecution the patentee had argued that its location ability was not limited to “a position in a grid pattern” and did not require a grid pattern overlay.  Rather its location sense was more “adaptable” and “refined.”  The courts found this clear prosecution history disclaimer and so the location term is properly construed to require “not merely a position in a grid pattern.”  This construction excused Nokia from infringement, since the accused Nokia system is arranged in a grid of 50-meter-by-50-meter bins.

“A Computer” – the claims all required “a computer” or “first computer.” The problem was that the accused devices performed the various functions across a set of computers. The district court construed “first computer” and “computer” to mean a single computer that can perform each and every function.  That construction was affirmed on appeal after the Federal Circuit reviewed the claims and specification for supporting evidence.

[I]t would defy the concept of antecedent basis—for the claims to recite “the computer” or “said first computer” being “further” programmed to do a second set of tasks if a different computer were to do those tasks instead.

Slip Op.  This interpretation was also confirmed by the prosecution history statement including a responsive argument submitted to the PTO titled ““Single computer needed in Reed v. additional software needed in Andersson.”  Reed is the Traxcell patent; Andersson was the prior art.  One computer requirement meant no infringement. 

Means For: The case against Sprint partially turned on a means-plus-function limitation: “means for receiving said performance data and corresponding locations from said radio tower and correcting radio frequency signals of said radio tower.”  The patentee pointed to an algorithm disclosed in the specification as the corresponding structural disclosure.  Under Section 112(f), a means-plus-function claim “shall be construed to cover the corresponding structure … in the specification and equivalents thereof.”  It was clear that Sprint did not use the identical algorithm, but the question was whether the “equivalent” penumbra of the claim was broad enough.  In order to determine equivalents under Section 112, the district court applied the function-way-result test generally used in DOE cases.  See Applied Med. Res. Corp. v. U.S. Surgical Corp., 448 F.3d 1324 (Fed. Cir. 2006).  Generally, the function-way-result test ends up with a quite narrow band of equivalents.  Here, the court found that the accused activity not proven to be done “substantially the same way” as that claimed and so was not an equivalent. An aspect of this doctrine that continues to create confusion is whether this “equivalent” evidence is an element of claim construction as suggested by the statute or instead post-construction infringement analysis.

Indefiniteness: Some of the claims were also invalidated as indefinite, even after a certificate of correction. In particular, the those claims required a “means for … suggesting corrective actions . . based upon . . . location” but the specification did not disclose how that might take place. On appeal, the Federal Circuit affirmed. “Although Traxcell demonstrated that the structure makes corrections based on other performance data, it hasn’t shown that any corrections are made using location.”

The Federal Circuit uses a simple if-then shortcut for its indefiniteness analysis of claims that include means-plus-function language. If the specification lacks sufficient structure to support the claimed means; Then the claim is invalid as indefinite.  This approach is probably too rule based. Rather, each time the Federal Circuit should use its lack-of-structure analysis to ask does the claim at issue “particularly point[] out and distinctly claim[] the subject matter which the inventor or a joint inventor regards as the invention.” 35 U.S.C. 112(b).

The four asserted patents U.S. Patent Nos. 8,977,284 (“the ’284 patent”), 9,510,320 (“the ’320 patent”), 9,642,024 (“the ’024 patent”), and 9,549,388. 

5 thoughts on “Disclaimer in Prosecution cannot be Recaptured in Litigation

  1. 2

    Too rule based? Isn’t there something in the law that says if it’s a “means” it has to be described in the specification?

    1. 2.1

      112f says that means elements will be construed to cover the disclosed structure, but it does not state that a claim which fails to provide a complete structural disclosure is automatically indefinite under 112b.

      1. 2.1.1

        Are you distinguishing between “cover” and “subject matter which the inventor regards as the invention”? Otherwise I’m not clear on what the issue is. Can you give an example of where we don’t know what structure is covered and yet the claim is still definite?

        And doesn’t this run up against Aristocrat? The federal circuit has long said that the fact that one of skill would be enabled to perform the function in some manner simply doesn’t have any bearing on the indefiniteness question, but your comment would seem to suggest that if one of skill was enabled to perform the function there would have to be some analysis that identified that the art knew of multiple different ways of achieving the function such that one would be unsure of which one was being claimed. Presumably, if one claimed a means plus function that the art knew EXACTLY ONE way of achieving the function, it would be both definite and enabled under this view but as soon as two competing means were known to the art it would lose the definiteness? Is that right?


          Presumably, if one claimed a means plus function that the art knew EXACTLY ONE way of achieving the function, it would be both definite and enabled under this view but“…

          … you would be screaming “no patent” for undue pre-emption.

          Random, your views across the various aspects of patent law simply are not sustainable together.

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