IP Law Daily, PATENT—Fed. Cir.: PTAB’s invalidation of curved treadmill patent affirmed, (Jul 21, 2026)

By Carolin Dennis, B.Sc., LL.B., LL.M.

Patent Trial and Appeal Board (PTAB) did not err in rejecting the patent owner’s narrow construction of the term “running surface” because it conflicts with the language in the specification.

In a non-precedential disposition, the U.S. Court of Appeals for the Federal Circuit affirmed the PTAB’s determination finding that several claims of Woodway USA Inc.’s curved treadmill patent were unpatentable as obvious. The Federal Circuit found that the patent owner failed to show that the PTAB’s obviousness determination was not supported by substantial evidence (Woodway USA, Inc. v. Lifecore Fitness, LLC, No. 25-1323 (Fed. Cir. Jul. 17, 2026)).

Woodway USA, Inc. (Woodway) owned the U.S. Patent 10,561,884 (’884 patent) generally directed to manually operated treadmills and mechanisms for controlling the motion of the treadmill’s running belt. Lifecore Fitness, LLC, dba Assault Fitness, (LifeCore) filed a petition for inter partes review of claims 30–34, 37–54, 57, and 59 of the ’884 patent. LifeCore argued that the claims containing the curved running surface limitation (i.e., all claims on appeal) would have been obvious over U.S. Patent 3,637,206 (Chickering) in combination with U.S. Patent 5,538,489 (Magid) and certain disclosures from the reference book Mechanisms & Mechanical Devices Sourcebook (Sclater) at the time of filing the ’884 patent application. LifeCore argued that Chickering’s single-belt embodiment, satisfied the “curved running surface” limitation because the disclosed belt of that embodiment follows the contour of rollers arranged in upward and downward-sloping planes, producing a curved central portion where the planes meet. Woodway contended that the claimed curved running surface is a surface with which a runner’s feet are intended to make contact when using a treadmill and, in Chickering, a runner’s feet are not intended to contact the belt at the area where the forward rollers meet the rearward rollers.

The PTAB agreed with LifeCore, finding that Chickering’s single-belt embodiment disclosed a curved running surface, as recited by claim 30, while rejecting Woodway’s expert testimony that limited the claimed “curved running surface” to be a surface that a runner’s feet would make contact with during normal use. The PTAB also rejected Woodway’s motivation to combine and secondary consideration arguments. The PTAB found claims 30–34, 37–39, 41, 45–49, 57, and 59 unpatentable as obvious over Chickering in combination with Magid and Sclater. Woodway appealed arguing that the PTAB erred in its obviousness determination because it applied an incorrect claim construction, and that under its view of the proper construction the PTAB’s findings were not supported by substantial evidence.

On appeal, Woodway contended that the PTAB implicitly construed the term “running surface” incorrectly to include portions of the running belt on which users would not be expected to place their feet. In Woodway’s view, the claimed “curved running surface” is limited to a surface that a “runner’s feet would typically make contact with when the user is running on the treadmill during normal use.” Under that construction, it contended that Chickering cannot disclose a “curved running surface” because the only portion of Chickering’s running belt that is “arguably curved is not a portion with which a user’s feet are expected or intended to make contact.”

The Federal Circuit found that neither party requested that the PTAB expressly construe the term “running surface,” and the PTAB did not construe this term. It merely rejected Woodway’s expert testimony regarding the plain and ordinary meaning of “running surface,” while making a fact finding regarding the differences between Chickering’s endless belt and the ’884 patent’s “curved running surface” limitation. Therefore, the Federal Circuit rejected Woodway’s attempt to recast a factual dispute as a claim construction issue to obtain de novo review. The Federal Circuit also noted that the PTAB correctly pointed out that the ’884 patent consistently describes the claimed “running surface” as a continuous surface that may comprise multiple regions (e.g., front, central, and rear regions) with varying geometric configurations (e.g., curved and linear portions). Thus, the Federal Circuit concluded that the PTAB did not err in rejecting Woodway’s narrow construction of the term “running surface” because that construction conflicted with the language in the specification.

Regarding the motivation to combine argument, Woodway did not dispute that the combination of Chickering, Magid, and Sclater teaches the “safety device” limitations. It contended that a person of skill would have had no reason to combine those references because Magid teaches away. However, the PTAB’s determination was supported by substantial evidence because it explained that a “person of skill would have modified Chickering to include a safety device as taught by Magid in order to reduce the risk of a user falling” based on the express teachings of those references and LifeCore’s expert’s, Dr.Giachetti, testimony. It further explained, relying on other expert testimony, that the evidence supported an obvious substitution of “Sclater’s one-way sprag-type bearing for Magid’s ratchet and pawl one-way mechanism to obtain predictable results, e.g., reduced noise and improved durability.” It then rejected Woodway’s teaching away arguments because those arguments did not concern the modification proposed in the petition. Therefore, the Federal Circuit concluded that the evidence, including the prior art disclosures and accompanying expert testimony, provide substantial evidence for the PTAB’s motivation to combine finding.

As for Woodway’s secondary considerations argument, the PTAB weighed Woodway’s evidence of secondary considerations and found that Woodway did not sufficiently establish a nexus between the unique features of the claimed invention and the evidence of secondary considerations. Here, the PTAB relied on Woodway’s failure to establish coextensiveness for purposes of a presumption of nexus and its failure to show that the alleged secondary considerations were attributable to the claimed safety features rather than unclaimed features of its relevant commercial treadmills. The PTAB specifically found Woodway’s witness testimony purporting that “safety is a critical factor for commercial success” not credible because that same witness testified that Woodway’s alleged commercial success could be due to other factors, such as Woodway’s reputation. Thus, the PTAB’s lack of nexus finding was supported by substantial evidence.

Accordingly, the Federal Circuit affirmed the PTAB’s decision.

The Case is No. 25-1323.

Judge: Lourie, A.

Attorneys: Kadie M. Jelenchick (Foley & Lardner LLP) for Woodway U.S., Inc. Andrew B. Turner (Brooks Kushman PC) for LifeCORE Fitness, LLC.

Companies: Woodway U.S., Inc.; LifeCORE Fitness, LLC

Cases: Patent FedCirNews