Only an Expert Can Offer Opinions on Obviousness

Feb 25, 2020

Reading Time : 3 min

HVLPO2, LLC (HVO) sued Oxygen Frog for infringement of U.S. Patent Nos. 8,876,941 and 9,372,488, directed to methods and devices for controlling an oxygen-generating system used to manage airflow for torch glass artists. The district court granted summary judgement to HVO and the case proceeded to a jury trial on Oxygen Frog’s assertions that the claims were obvious over two prior art references. At trial, Oxygen Frog introduced deposition testimony of a glass blowing artist whose online video was offered as prior art. The witness had not been qualified as an expert witness, and while proffered as a fact witness, he opined that it would have been obvious to modify a prior art system in a way that matched the claimed invention. HVO objected, arguing improper expert testimony. The district court overruled the objection but provided limiting instruction to the jury that “a witness such as [the glass blowing artist] certainly can offer his observations and explain to you how a system works and what he thinks would occur to him from his perspective would or would not be obvious.” The district court further instructed the jury that the testimony did not answer the ultimate question of obviousness. The jury then found the claims to be obvious. The district court subsequently denied HVO’s motion for a new trial that based upon the artist’s testimony.

On appeal, the Federal Circuit reversed and remanded for a new trial, holding that it was improper to admit the lay witness testimony and that the district court’s limiting instruction was insufficient to cure the substantial prejudice caused by the testimony. The opinion cites Federal Rule of Evidence 702 on expert witness testimony, emphasizing that issues of infringement and validity “are analyzed in great part from the perspective of a person of ordinary skill in the art,” and that a witness who is not “‘qualified as an expert by knowledge, skill, experience, training, or education’ in the pertinent art cannot assist the trier of fact to understand the evidence or to determine a fact in issue.” As a consequence, the Federal Circuit said that allowing a non-expert witness to testify on issues of non-infringement or invalidity is an abuse of discretion.

Citing also to Federal Rule of Civil Procedure 26, the Federal Circuit noted that certain protections are in place with expert witnesses that allow both sides in a case to prepare adequately and without surprise. Here, Oxygen Frog provided neither notice to HVO of anticipated expert testimony nor a written expert report. To contrary, Oxygen Frog argued that it was not required to comply with the Rules governing experts since the witness was not proffered as an expert. Further, according to Oxygen Frog, its witness only offered views based on perception and experience. The Federal Circuit rejected these arguments, stressing that the opinion testimony was directed to the central legal and technical question of the dispute.

The Federal Circuit also dismissed Oxygen Frog’s contention that any error associated with the admission of a lay expert’s testimony was harmless, explaining that by permitting improper testimony, the district court deprived HVO of its right to have the obviousness inquiry decided based on an admissible, qualified expert testimony and prejudiced it by not providing the relevant procedures to ensure the reliability and relevance of the testimony.

While the Federal Circuit acknowledged it might be possible for a district court to cure inadmissible testimony by instructing the jury to disregard it, the error in the present case was not cured and the new trial was necessary.

Practice tip: Determining the expected scope of witness testimony during trial requires care and attention early in the case. To ultimately have a witness opine on questions of validity or infringement, they must be qualified as an expert, and all necessary Federal Rules governing expert witnesses must be adhered to. Failure to do so can be case determinative.

HVLPO2, LLC v. Oxygen Frog, LLC, No. 2019-1649 (Fed. Cir. Feb. 5, 2020)

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