Trademark Functionality Did Not Require Literal Patent Infringement

In FUJI KOGYO CO., LTD v. PACIFIC BAY INTERNATIONAL, INC., (6th Cir.; Augiust 23, 2006) Fuji argued that the district court erred when it considered the utility patents as evidence of design functionality (for fishing rod line guides) without first determining whether Fuji’s trademarked product configuration was claimed in any of the patents. "Fuji dissects the language of its patents in an attempt to distinguish its claims from similar features in its trademarks," wrote Circuit Judge Boggs. "In light of TrafFix, we find these arguments unconvincing:"

Fuji argues that we must remand this case to the district court so that court can conduct a claim construction analysis in the first instance before we can evaluate the patents under the doctrine of equivalents. This argument fails, not because it is an incorrect statement of the law regarding infringement, but because the district court was never charged with determining the validity of the patents. Rather, it was evaluating and weighing the patent as evidence of functionality. See Applied
Med. Res. Corp. v. U.S. Surgical Corp., 448 F.3d 1324, 1332 (Fed. Cir. 2006). The patents in this case were probative evidence, see Fed. R. Evid. 401, and the district court, as the trier of fact, could credit or discount the patent evidence by considering the likelihood that various features of the trademarked designs were claimed in any of the patents. Accordingly, we affirm the district court’s use of Fuji’s patents in
its functionality analysis and hold that an evaluation under the doctrine of equivalents is appropriate in the course of this kind of factual finding.

We conclude, in light of the applicable law, that the district court’s determination that Fuji’s registered and claimed trademarks in its previously patented designs were functional was not clearly erroneous. The court’s investigation was properly illuminated by the language of the patents, consideration of the doctrine of equivalents, and witness testimony—in short all the evidence considered during the trial.