Tessenderlo Kerley, Inc. v. D&M Chem, Inc., CV-11-3112-LRS, Slip Op. (E.D. Wa. Mar. 25, 2013) (Suko, J.)
Tessenderlo Kerley, Inc. (“TKI”) and D&M Chem manufacture competing sun protectants for crops. TKI makes and sells products under the brand names Surround® and Purshade®. These products coat plant surfaces with a protective film that scatters light and dissipates heat, resulting in enhanced photosynthesis.
D&M, of Moxee, Washington (population 3,308), distributes a crop protectant under the brand name Eclipse®. According to TKI, D&M’s Eclipse® product, like Purshade®, is a calcium carbonate-based liquid used to control sunburn and minimize the effects of heat stress in plants.
In August 2011, TKI sued D&M for patent infringement in the Northern District of California. TKI claimed that D&M infringed U.S. Patent Nos. 6,110,867 (“Method for Providing Enhanced Photosynthesis”) and 6,464,995 (“Treated Horticultural Substrates”) by distributing the Eclipse® crop protectant. D&M successfully moved to transfer the case to the Eastern District of Washington.
Following a Markman hearing in Yakima, Washington (home of the world-famous Sun Dome, pictured below), Judge Suko entered a 36-page order construing five claim terms, including the term “effective amount,” which appears in claim 1 of the ‘867 patent:
1. A method for enhancing photosynthesis of a horticultural crop by increasing carbon dioxide assimilation of said horticultural crop which comprises applying to the surface of said horticultural crop an effective amount of one or more highly reflective particulate materials, said particulate materials being finely divided, and wherein the particles as applied allow for the exchange of gases on the surface of said crop and the finely divided particulate materials have a median individual particle size below about 3 microns.
D&M argued that the claim 1 was invalid for indefiniteness under 35 U.S.C. § 112 ¶ 2 because one of ordinary skill in the art would not understand what amount of highly reflective particulate materials constitutes an “effective amount” for a given application. Notably, D&M did not rely on expert testimony in support of its indefiniteness argument, and it represented that it intended to file a separate motion for summary judgment of indefiniteness.
TKI argued that the term “effective amount” was not indefinite and was defined in the specification and prosecution history as “an amount that is sufficient to increase photosynthesis of horticultural crops by increasing carbon dioxide assimilation of said crops.” During the Markman hearing, TKI’s counsel argued that a person of ordinary skill in the art would be able to determine the amount necessary to enhance photosynthesis by measuring “carbon dioxide uptake, stomatal conductance and the like” using available equipment.
The Court held that D&M failed to meet its “heightened burden” of proving indefiniteness: “D&M failed to offer sufficient evidence that a person of ordinary skill in the art could not discern what would be considered ‘effective amount’ for the given commercial purpose of improving photosynthesis as applied to horticultural crops.” The Court was critical of D&M’s “unsupported assertion” in in its claim construction brief that “effective amount” was indefinite, noting that its argument “is no substitute for evidence to this effect.”
Ultimately, the Court adopted TKI’s proposed construction of “effective amount,” and the parties filed a stipulation for dismissal four days after Judge Suko entered his claim construction order.
The obvious takeaway here is that accused infringers arguing indefiniteness should consider supporting their arguments with extrinsic evidence, including expert testimony. As I have argued before, indefiniteness is an issue of claim construction and, as such, little (if any) extrinsic evidence should be required to determine whether a claim term is indefinite. But who cares what I think? The Federal Circuit has looked to extrinsic evidence in determining whether a claim term is indefinite; therefore, accused infringers should not overlook extrinsic evidence when asserting indefiniteness. See, e.g., Datamize, LLC v. Plumtree Software, Inc., 417 F.3d 1342 (Fed. Cir. 2005).







