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In Opposing a Motion for Summary Judgment of Noninfringement Under the Doctrine of Equivalents, Patentee Must Present Particularized Evidence of Equivalents to Meet Its Evidentiary Burden

06-1407
February 27, 2007

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Last Month at the Federal Circuit - March 2007

Judges: Rader, Dyk (author), Whyte (sitting by designation)

[Appealed from: M.D. Tenn., Judge Echols]

In AquaTex Industries, Inc. v. Techniche Solutions, No. 06-1407 (Fed. Cir. Feb. 27, 2007), the Federal Circuit affirmed the grant of SJ of noninfringement because AquaTex Industries, Inc. (“AquaTex”) did not satisfy its burden to present particularized evidence of equivalents in opposition to a motion for SJ by Techniche Solutions (“Techniche”).

AquaTex is the assignee of U.S. Patent No. 6,371,977 (“the ’977 patent”). The ’977 patent is directed to a method for cooling a person through evaporation by use of a multilayered, liquid-retaining composite material as a garment. Claims 1 and 9 of the ’977 patent are directed to a method performed using a device comprising, among other things, “a fiberfill batting material.” Techniche manufactures multilayered, liquid-retaining composite materials for use in evaporative cooling garments. Techniche uses a fabric called Vizorb®, which consists of both natural and synthetic fibers, as a filler layer in its composite materials.

AquaTex sued Techniche for contributory infringement, alleging that Techniche made a product that consumers used to perform the method of claims 1 and 9 of the ’977 patent. In 2004, Techniche moved for SJ of noninfringement. While it conceded that its commercial product met most limitations of claims 1 and 9 of the ’977 patent, it argued that its product did not satisfy the “fiberfill batting material” limitation of the claim because Vizorb® incorporates both natural and synthetic fibers, and only materials containing exclusively synthetic fibers constitute “fiberfill.”

The district court construed the phrase “fiberfill batting material” to require only synthetic batting material, and therefore found no literal infringement, as Vizorb® includes natural fibers as well as synthetic fibers. The district court also found that the claim of infringement under the DOE was barred by prosecution history estoppel. On appeal for the first time, in AquaTex Industries, Inc. v. Techniche Solutions, 419 F.3d 1374 (Fed. Cir. 2005), the Federal Circuit affirmed the district court’s finding of no literal infringement. However, the Court also held that prosecution history estoppel did not bar consideration of the DOE because neither the arguments nor the narrowing amendments made during prosecution had any relation to the composition of the fiberfill batting material. The Court then remanded the case to the district court to determine if the claims were infringed under the DOE.

On remand, the district court again granted SJ of noninfringement. It held that “AquaTex’s narrowing amendments made during prosecution of the ’977 patent ‘surrender[ed] subject matter within which [Techniche’s] product falls’ and therefore AquaTex was barred by prosecution history estoppel from asserting infringement by equivalents.” Slip op. at 5 (alterations in original). As an alternative ground for SJ, the district court held that AquaTex had failed to prove infringement under the DOE because AquaTex did not demonstrate that Techniche’s filler layer performs substantially the same function in substantially the same way as the patented method. Critical to the district court’s finding was its determination that AquaTex did not show that Techniche’s “filler layer includes a hydrophobic material, like the fiberfill used in [AquaTex’s] product, to create air pockets to promote evaporation.” Id. at 6 (alteration in original). AquaTex appealed again.

On appeal for the second time, the Federal Circuit held that the district court had again erred in concluding that prosecution history estoppel barred AquaTex from asserting the DOE. The district court stated that this approach was foreclosed by the court’s prior opinion, which held that “[t]he subject matter surrendered by the narrowing amendment bears no relation to the composition of the fiberfill batting material.” Id. at 7-8 (alteration in original).

The Federal Circuit also found that the district court had erred in its analysis of its alternate ground for SJ. A finding of infringement under the DOE requires a showing that the difference between the claimed invention and the accused product or method is insubstantial or that the accused product or method performs substantially the same function in substantially the same way with substantially the same result as each limitation of the patented product or method. The district court determined that the function of the “fiberfill batting material” was to promote evaporation, and the way it did so was by using hydrophobic material to create air pockets. Although the district court asserted that its conclusion regarding the function of the invention came from reading the specification as a whole, the Federal Circuit did not find support for this conclusion in the specification, and instead determined that the district court found these “distinguishing features” in information taken from AquaTex’s Web site describingAquaTex’s product. The Court stated that “the identification of the elements of the function, way, result test solely ‘entails an examination of the claim and the explanation of it found in the written description of the patent,’ as well as ‘[i]n some cases[] the patent’s prosecution history.’” Id. at 11 (alterations in original). Therefore, the Court found that the district court committed error when it relied on features not disclosed in the ’977 patent in concluding that Techniche’s Vizorb® layer was not equivalent to the “fiberfill batting material” limitation.

Although the Federal Circuit found that the district court erred in the grounds on which it granted SJ, the Court affirmed the grant of SJ after conducting its own de novo review of whether Techniche’s product infringed under the DOE. The Court agreed with AquaTex that the function of the fiberfill batting material was to retain and distribute absorbent materials throughout the filler layer, rather than to promote evaporation. However, the Court held that AquaTex failed to meet its evidentiary burden of providing particularized testimony and linking argument on a limitation-by-limitation basis to demonstrate a genuine issue of material fact as to the existence of equivalents. To meet this burden, AquaTex was required to provide testimony of a person of ordinary skill in the art who, on a limitation-by-limitation basis, could explain the insubstantiality of the differences between the patented method and the accused product or discuss the function, way, result test.

AquaTex did not provide this evidence. The only evidence AquaTex presented on the issue of equivalents was the deposition of Chris Frost, Techniche’s Chief Executive Officer. Although Frost explained how Techniche’s product operated, his testimony did not specifically address equivalents or compare Techniche’s product to the patented method on a limitation-by-limitation basis, as required.

Thus, the Federal Circuit concluded that AquaTex had failed to demonstrate a genuine issue of material fact that would prevent the grant of SJ because they “only provided lawyer argument and generalized testimony about the accused product.” Id. at 15.