Red Dog Mobile Shelters, LLC v. Kat Industries, Inc.
664 F. App'x 905
| Fed. Cir. | 2016Background
- Red Dog Mobile Shelters sued KAT, alleging KAT’s Tuffy shelter infringed U.S. Patent No. 8,534,001, asserting multiple claims (including claim 60 and several other claims represented by claim 44).
- The ’001 patent claims shelters with rails/elongate members that "support" or "elevate" a floor above a substrate and, in some claims, a ballast beneath specified locations; the specification emphasizes rails that lift the floor to create a substantially enclosed sub-floor region and exploit airflow (Bernoulli effect).
- KAT moved for summary judgment of non-infringement; the district court granted summary judgment, finding no genuine dispute that the accused shelter did not meet the "support" and "elevate" limitations and also lacked evidence for the "ballast" limitation of claim 60.
- Red Dog’s infringement theory relied on an expert who opined (via structural/physics reasoning) that side or raised elements of the KAT shelter could "support" or "elevate" the floor by load transfer and that the shelter’s bottom plate constituted part of the rails.
- The district court rejected that interpretation as inconsistent with the patent’s emphasis on rails placed beneath the shelter to raise the floor, and found the expert’s claim interpretation not consistent with how a person of ordinary skill would read the patent.
- The Federal Circuit reviewed the grant of summary judgment de novo, affirmed the district court’s constructions of "support" and "elevate," and affirmed summary judgment of non-infringement as to all asserted claims.
Issues
| Issue | Plaintiff's Argument (Red Dog) | Defendant's Argument (KAT) | Held |
|---|---|---|---|
| Claim construction: meaning of "support" (claims except 60) | "Support" should encompass raised/side elements that, via stiffness and load transfer, bear part of the load even if not directly beneath the shelter | "Support" means rails that sit beneath and physically support/elevate the shelter as described in the specification | Court: "support" construed consistent with specification—rails beneath shelter; Red Dog’s physics/load-transfer reading rejected; summary judgment for KAT affirmed |
| Meaning of "elevate" in claim 60 | "Elevate" should cover cases where the floor is above the substrate by virtue of the floor’s own thickness and where the bottom plate is part of the rails | "Elevate" requires rails that lift the floor above the substrate creating a gap as described in the patent | Court: "elevate" requires rails that lift the floor above the ground; Red Dog’s interpretation (any floor with thickness is "elevated") is unreasonable; claim 60 not met |
| Sufficiency of expert evidence to create triable issue | Expert’s physics analysis (Hooke’s Law, Newton’s Third Law) shows load transfer and thus support/elevation by the accused structure | Expert interpretation is inconsistent with ordinary skilled artisan reading and the patent’s description; insufficient to raise genuine dispute | Court: Expert’s analysis did not establish claim meaning or infringement; district court properly discounted it; summary judgment affirmed |
Key Cases Cited
- Akzo Nobel Coatings, Inc. v. Dow Chem. Co., 811 F.3d 1334 (Fed. Cir. 2016) (summary judgment appropriate when no reasonable factfinder could find accused product meets every claim limitation)
- Wright v. Excel Paralubes, 807 F.3d 730 (5th Cir. 2015) (standard for reviewing summary judgment)