The Federal Circuit Clarifies Who Can Be an Expert in Patent Cases
In September 2024, the Federal Circuit clarified the necessary qualifications for a technical expert to testify in a patent lawsuit, holding that while an expert must possess ordinary skill in the art, they need not have possessed such skill “at the time of the alleged invention.” Osseo Imaging, LLC v. Planmeca USA Inc. 2024 WL 4031140, at *3 (Fed. Cir. Sept. 4, 2024).
Expert witnesses play a critical role in patent litigation, where judges and juries without technical training are expected to adjudicate often highly technical issues related to the patented invention, the accused products, and the state of the art in the relevant industry at the time of the invention. But without the right specialized knowledge, training, or experience, a witness may not qualify as an expert and their opinions will not be helpful. Many issues in a patent lawsuit—including claim construction, infringement, and validity—require assessing evidence from the perspective of a hypothetical “person of ordinary skill in the art.” Thus, to be qualified to offer technical expert testimony in a patent case, “an expert must at a minimum possess ordinary skill in the art.” Kyocera Senco Industrial Tools Inc. v. International Trade Commission, 22 F. 4th 1369, 1377 (Fed. Cir. 2022).
In Osseo Imaging, the patent owner Osseo argued at trial that a person of ordinary skill in the art would have, among other qualifications, three to five years of experience in a diagnostic imaging environment that uses the techniques described in Osseo’s patents. On cross-examination, the accused infringer sought to disqualify and discredit Osseo’s technical expert, Dr. Omid Kia, by showing that, while he met the definition of a person with ordinary skill by the time of trial, he lacked the required diagnostic imaging experience at the time of the invention in 1999. The district court judge rejected the argument, and the jury found in favor of the patent owner. Osseo Imaging, LLC v. Planmeca USA Inc., No. 1:17-cv-01386, 2023 WL 1815975, at *3 (D. Del. Feb. 8, 2023).
On appeal to the Federal Circuit, the accused infringer Planmeca again raised the issue of the expert witness’s qualifications, arguing that the district court erred as a matter of law because “although Dr. Kia became a person of ordinary skill 8 to 10 years after the time of the invention, he was not so skilled at the time of the invention, and thus the verdict cannot be supported by his testimony.” 2024 WL 4031140 at *2. Planmeca argued that the Federal Circuit’s prior decision in Kyocera supported its reasoning, pointing to the holding there that an expert witness must “be qualified to offer expert testimony on issues from the vantage point of an ordinarily skilled artisan in a patent case.” Id., at *3 (emphasis in original). The Federal Circuit summarily rejected this argument and found not only that Planmeca was inferring too much from Kyocera and that there was no support for Planmeca’s proposed timing requirement in the case law, but that it made little sense to impose such a timing requirement because “an expert can acquire the necessary skill level later and develop an understanding of what a person of ordinary skill knew at the time of the invention.” 2024 WL 4031140 at *3. The court concluded that an expert must only possess ordinary skill in the art, nothing more.
The Osseo decision again confirms that when hiring an expert for a patent dispute (whether in district court or before the U.S. Patent and Trademark Office), it is crucial to select an expert witness who meets or exceeds the definition of a person of ordinary skill in the art. Of course, that definition is unlikely to have been settled by the time the expert is engaged, so litigants should be conservative in their selection criteria and seek an expert witness who will qualify under any reasonable definition. Relevant factors that go in to such a definition include “1) the educational level of the inventor; (2) type of problems encountered in the art; (3) prior art solutions to those problems; (4) rapidity with which innovations are made; (5) sophistication of the technology; and (6) educational level of active workers in the field.” See Environmental Designs, Ltd. v. Union Oil Co. of California, 713 F.2d 693, 696 (1983).
The Osseo decision also clarified that an expert witness only needs to have this level of skill, regardless of when they gained such experience. However, the court left litigants with an explicit warning, stating that “[i]n practice, the fact that the expert was not a person of ordinary skill at the time of the invention may well be used during cross examination to undermine the credibility of the expert.” 2024 WL 4031140 at *3. Thus, as the court observed, there remains some risk in using an expert who only gained the experience necessary to testify from the perspective of an ordinarily skilled artisan well after the invention date. Litigants should consider this warning when making hiring decisions. And when an expert with later-acquired experience is used, the expert should be encouraged to explain how they are able to offer opinion testimony from the perspective of someone who acquired similar experience some time earlier than the witness did.
Reprinted with permission from the November 1, 2024 edition of The Intellectual Property Strategist© 2024 ALM Global Properties, LLC. All rights reserved.
