Willis Electric Co. v. Polygroup Ltd. (Macao Commercial Offshore)

Willis Electric v. Polygroup, decided February 17th, 2026. The Federal Circuit, in an opinion by Chief Judge Moore, affirmed a forty-two-million-dollar patent judgment. It held that the district court did not abuse its discretion in admitting the patentee's damages expert: once the court found her apportionment methodology reliable, the challenges to how she applied it went to the weight of her testimony, not to its admissibility. Here's the brief.

Willis Electric owns United States Patent 8,454,186, which covers pre-lit artificial trees. The trees have separable, modular trunk sections. Joining two sections makes the mechanical and the electrical connection at the same time, at any rotational orientation. In the prior art, assembly took two steps — join the trunk sections, then manually connect the electrical cords.

Willis sued Polygroup in the District of Minnesota. Polygroup filed sixteen petitions for inter partes review. After proceedings before the Patent Trial and Appeal Board and two prior trips to the Federal Circuit, only three claims of the '186 patent remained in the district court, and Willis narrowed its case to a single one — claim 15.

Before trial, Polygroup moved under Rule 702 to exclude the opinions of Willis's damages expert, Michele Riley. The district court denied that motion. The jury found claim 15 infringed and not invalid, and awarded Willis forty-two million, four hundred ninety-four thousand, seven hundred seventy-two dollars — about four dollars per tree. Polygroup then moved for judgment as a matter of law that the claim was obvious, and for a new trial on damages. Senior Judge Ericksen denied both motions, and Polygroup appealed.

Two questions were presented: whether substantial evidence supported the jury's verdict of nonobviousness, and whether the damages expert should have been excluded under Rule 702.

Rule 702, as amended in 2023, requires the proponent to demonstrate reliability to the court by a preponderance. The court recalled its own decision from the previous year, sitting en banc, in EcoFactor v. Google, which clarified the scope of Rule 702 and the district court's gatekeeping role.

The standards of review were split. The court reviewed the denial of judgment as a matter of law under Eighth Circuit law, and reviewed evidentiary rulings for abuse of discretion — but applied its own circuit's law to admissibility questions that turn on the patent-law standards governing damages.

On obviousness, Polygroup argued that a skilled artisan would have been motivated to modify a prior-art tree to use coaxial barrel connectors. Willis's expert testified that the substitution would have required four separate redesign steps, and would have abandoned the reference's own teaching about aligning a fixed-orientation tree. The district court had faulted Polygroup for failing to grapple with the specific design challenges the prior-art tree posed, and for offering little concrete evidence that those changes were within a skilled artisan's capability. The Federal Circuit held that substantial evidence supported the jury's presumed finding that there was no motivation to combine.

On damages, Riley used two independent methods. An income approach, apportioned to claim 15, compared profit premiums on patented and unpatented trees to reach a range of four dollars thirty to twenty dollars. A market approach, using comparable licenses, produced a range of two to five dollars. She combined them, then applied the Georgia-Pacific factors to select five dollars. Polygroup's expert had arrived at twenty-five to thirty-five cents.

Polygroup did not argue that any of these approaches was categorically improper. It argued each had been unreliably applied, and that Riley had not adequately explained her methodology to the jury.

The district court had found the opinion, while not bulletproof, incorporated reliable apportionment methodologies grounded in sufficiently comparable licenses and financial data. The Federal Circuit found no abuse of discretion.

Willis Electric applies EcoFactor rather than narrowing it. The gate is real: the district court must find reliability by a preponderance before an opinion reaches the jury. But once that finding is made, disputes over data selection, assumptions, and modeling choices are for cross-examination and contrary evidence. The court tied that allocation to the nature of the remedy — a reasonable royalty, it said, necessarily involves an element of approximation and uncertainty.

Willis Electric Co. v. Polygroup Ltd., 166 F.4th 1363, decided in the Federal Circuit on February 17th, 2026. I'm Kyle Coleman. Thanks for watching.