Claim Construction: Too Much Structure Will Spoil the Brew
In affirming-in-part grants of summary judgment on non-infringement by two separate district courts, the U.S. Court of Appeals for the Federal Circuit reiterated the role of a district court in claim construction is to give meaning to the limitations actually contained in the claims, “not to redefine claim recitations or to read limitations into the claims.” American Piledriving Equip., Inc. v. Geoquip, Inc., Case Nos. 10-1283, -1314 (Fed. Cir., Mar. 21, 2011) (Linn, J.).
American Piledriving filed suit against Geoquip in the Eastern District of Virginia and separately against Bay Machinery in the Northern District of California alleging that each infringed its patent by selling piledrivers manufactured by Hydraulic Power Systems. The patent in issue relates to counterweights for “vibratory” piledrivers, which rely on vibrations to drive piles into the ground. The representative claim recites, inter alia, a limitation requiring “counterweights having a cylindrical gear portion and an eccentric weight portion integral with said cylindrical gear portion, said eccentric weight portion having at least one insert-receiving area formed therein.”
A Markman hearing was held in each case and each of district courts consistently construed the term “integral” to mean “formed or cast of one piece.”
The district courts diverged, however, on their construction of “eccentric weight portion” and “insert-receiving area.” The California district court construed “eccentric weight portion” to mean “the bottom portion of the counterweight, which extends forward from the front face of the gear portion, containing more weight than the top portion due to its larger mass, including at least one insert receiving area formed therein to receive at least one solid tungsten rod.” The Virginia district court construed the same term to mean “that portion of the counterweight that extends either forward or rearward from the front or back face of the gear portion such that it shifts the center of gravity radially outward from the gear’s rotational axis.”
With regard to the term “insert-receiving area,” the Virginia district court construed that term to mean “a bore located, at least in part, within the eccentric weight portion that is shaped to hold securely a solid insert member,” whereas the California district court construed the same claim language to mean “a bore formed in the eccentric weight portion of the counterweight, which extends fully through the gear portion and fully through the eccentric weight portion of the counterweight capable of receiving a solid tungsten rod.”
In both the California and Virginia actions, the defendants moved for, and the district courts granted, summary judgment of non-infringement. The summary judgment grants were based on each court’s constructions of the disputed phrases “integral,” “insert-receiving area” and “eccentric weight portion.” American Piledriving appealed.
On appeal, American Piledriving argued that the district courts misconstrued these three terms. The Federal Circuit affirmed the Virginia court’s construction of each of these claim terms, as well as the California court’s construction of “integral” (which was identical to that of the Virginia court).
In upholding the Virginia constructions, the Federal Circuit found that the California constructions imported unnecessary limitations into the construction of “eccentric weight portion” and “insert-receiving area.” In its analysis, the Court reviewed the claims, the specification and the file history as it related to each of these terms. With regard to both “eccentric weight portion” and “insert-receiving area,” the Court found that there was no support in the intrinsic evidence for the additional structural limitations imported by the California district court.
The Federal Circuit affirmed both of the district court’s grants of summary judgment of non-infringement with regard to the accused products.