Pods v. Porta Stor (Fed. Cir. 2007)
Pods and Porta Star are competing storage and moving companies. Pods sued Porta Stor for patent infringement based on its patent directed to a method and apparatus for moving a storage container in and out of a truck. A jury found infringement and the judge held the patent not invalid.
On appeal, Porta Star focused-in on the claim term "carrier frame." That term was used in both claim 1 and claim 29. The lower court applied diverging meanings to the two instances, but no-one could explain why the claim construction should vary from the traditional "presumption that the same terms appearing in different portions of the claims should be given the same meaning unless it is clear from the specification and prosecution history that the terms have different meanings at different portions of the claims."
The parties agree that the structure described as a “carrier frame” in claim 1 is “a four-sided or rectangular-shaped carrier frame” that surrounds the container on all sides. . . . PODS has pointed to no evidence in the specification or the prosecution history that the term “carrier frame” in claim 29 has any meaning other than the uncontested meaning in claim 1.
The agreed definition of claim 1 construed "carrier frame" as four-sided frame, and because "the only embodiments disclosed in the specification are four-sided," the CAFC held that the claim 1 definition should prevail throughout the claimset. Based on this claim construction, the court found non-infringement.
Notes: The problem with this decision is that claim 1 explicitly limits a carrier frame with four sides while claim 29 only includes the limitation "carrier frame:"
Claim 1: . . . carrier frame including right and left longitudinal elements [and] having front and rear transverse elements . . .
Claim 29: . . . a carrier frame . . .
Despite this clear textual difference, the CAFC determined that the carrier frame of claim 29 must be defined as having four sides because (a) the parties agreed that claim 1 requires a four-sided carrier frame and (b) the only embodiments included four-sided carrier frame.
The court also denied coverage under the doctrine of equivalents because of prosecution estoppel -- in particular, the patentee had argued against a rejection of claim 1 by stating that claim 1 required a rectangular frame.
Why the patentee lost: It used the word "invention" when arguing against the rejection of claim 1: "the present invention which allows the carrier frame to be elevated and positioned as a rectangular-shaped frame with respect to the container, the vehicle and the ground.”