Last Month at the Federal Circuit
Last Month at the Federal Circuit

January 2013

Claim Vitiation Is Not an Exception to DOE


Judges:  Rader (author), Newman, Plager
[Appealed from S.D. Iowa, Senior Judge Wolle]

In Deere & Co. v. Bush Hog, LLC, Nos. 11-1629, -1630, -1631 (Fed. Cir. Dec. 4, 2012), the Federal Circuit vacated the district court’s construction of the term “into engagement with” and reversed the associated grant of SJ for noninfringement.  The Court also affirmed the construction of “rotary cutter deck” and the determination that the terms “substantially planar” and “easily . . . washed off” do not render the asserted claims invalid under 35 U.S.C. § 112.

Deere & Co.’s (“Deere”) U.S. Patent No. 6,052,980 (“the ’980 patent”) discloses an “easy clean dual wall deck” for a rotary cutter.  Claim 1 of the ’980 patent requires an upper deck wall to be “sloped . . . into engagement with, and being secured to, said lower deck wall.”  Deere filed suit against Bush Hog, LLC and Great Plains Manufacturing, Inc. (collectively, “Defendants”), alleging infringement. 

The district court construed the term “into engagement with” to mean “brought into contact with,” and construed “being secured to” as “fastened or attached.”  Slip op. at 4.  The district court granted SJ of noninfringement, holding Deere did not raise a genuine issue of material fact as to literal infringement because the upper deck walls do not come into contact with the lower deck walls in any of the Defendants’ accused products.  Moreover, the district court held that Deere could not assert infringement under the DOE because doing so would vitiate the “into engagement with” limitation.  Deere appealed.

On appeal, the Federal Circuit held that the district court erroneously construed the term “into engagement with” to require direct contact between the upper and lower deck walls.  Clarifying that “into engagement with” and “being secured to” convey distinct meanings, the Court construed “into engagement with” to include indirect contact.


[T]he vitiation test cannot be satisfied by simply noting that an element is missing from the claimed structure or process . . . .  If mere observation of a missing element could satisfy the vitiation requirement, this ‘exception’ would swallow the rule.  Slip op. at 11.

With regard to the DOE, the Court reiterated that “vitiation” is not an exception to the DOE.  The district court had construed “contact” to require “direct contact,” and thus found that allowing “no direct contact” for purposes of the DOE would vitiate the district court’s construction of the term “into engagement with.”  In the Federal Circuit’s view, the district court erred by invoking the vitiation exclusion in this context because “a reasonable jury could find that a small spacer connecting the upper and lower deck walls represents an insubstantial difference from direct contact.”  Id. at 11.  According to the Court, “the vitiation test cannot be satisfied by simply noting that an element is missing from the claimed structure or process because the doctrine of equivalents, by definition, recognizes that an element is missing that must be supplied by the equivalent substitute.  If mere observation of a missing element could satisfy the vitiation requirement, this ‘exception’ would swallow the rule.”  Id.

Addressing the additional claim construction arguments, the Court affirmed the construction of the remaining terms.  The Court first affirmed the district court’s construction of “rotary cutter deck” as “the blade housing on a power mower,” but the Court refused to limit the term to a device mounted to a tractor.  Id. at 14.  Next, the Court affirmed the district court’s determination that the limitations “substantially planar” and “easily . . . washed off” failed to render the respective claims indefinite, and, thus, the terms are not invalid under 35 U.S.C. § 112, ¶ 2.

Accordingly, the Federal Circuit remanded the case to the district court for further proceedings consistent with its opinion.