In this case, Kyocera Senco Industrial Tools Inc. brought a complaint against Koki Holdings America Ltd. for infringement of several patents related to Koki’s importation of gas spring nailers in the International Trade Commission (ITC). The claims of the asserted patents were generally directed to fastener driving tools and methods for controlling fastener driving tools. To support its case, Kyocera offered testimony from an engineering expert, Dr. John Pratt. Dr. Pratt had advanced degrees in engineering and vast experience in the design and manufacture of fastener driving tools, but no experience specifically in designing power nailers.
During claim construction, Koki proposed a definition of a skilled artisan that required, among other things, at least two years of experience in power nailer design. Kyocera did not contest the definition, or object after it was adopted by the administrative law judge (ALJ). Relying on this definition, Koki moved to exclude Dr. Pratt’s testimony on the basis that he did not qualify as a person of ordinary skill in the art because he lacked the required experience in power nailer design. The ALJ agreed, but only excluded Dr. Pratt from testify regarding infringement under the doctrine of equivalents. The ALJ permitted Dr. Pratt to testify as to literal infringement.
Both parties challenged the ALJ’s partial exclusion on appeal. Kyocera argued that Dr. Pratt should have been allowed to testify on both infringement issues, while Koki argued that Dr. Pratt should have never been allowed to testify at all.
The Federal Circuit agreed with Koki, and held that an expert must, at a minimum, possess ordinary skill in the art to offer testimony from the perspective of a skilled artisan, including on issues of claim construction, invalidity and infringement. Regarding literal infringement, the Federal Circuit explained that while proof of literal infringement does not always require testimony from an expert, an expert must possess at least ordinary skill in the art when such testimony is offered. That is, it makes no difference whether the expert is testifying about literal infringement or infringement under the doctrine of equivalents—the minimum qualifications to testify remain the same. The court further explained that its finding in this case did not contradict prior decisions holding that an expert may qualify as having a higher level of skill in the art, i.e., exceptional skill in the art.
Because Dr. Pratt’s experience failed to meet the definition of ordinary skill in the art, the Federal Circuit held that his proffered testimony on both literal infringement and infringement under the doctrine of equivalents was neither relevant nor reliable.
Practice Tip: Here, testimony from an expert who appeared to possess exceptional experience in a general field of study was excluded based on a relatively narrow definition of the level of skill in the art. This case should serve as a reminder to all parties to carefully consider both the qualifications of their experts and the potential implications of narrowly defining the level of skill in the art early in litigation, and to preserve objections when an expert’s qualifications and the level of skill may not align.
Kyocera Senco Indus. Tools Inc. v. Int’l Trade Comm’n, 22 F.4th 1369 (Fed. Cir. 2022).