IP Law Daily, PATENT—Fed. Cir.: Noninfringement and validity rulings affirmed in patent dispute between building material manufacturers, (Oct 17, 2025)

By Saurabh Kashyap, B.A., LL.B., LL.M.

District court correctly construed “integral boss” limitation and properly rejected indefiniteness challenge to “sliding” and “causes” terms in the asserted patents.

The U.S. Court of Appeals for the Federal Circuit affirmed the Northern District of Texas’s rulings in a patent infringement dispute between Barrette Outdoor Living, Inc. and Fortress Iron, LP, upholding findings of noninfringement and no invalidity for indefiniteness. The court held that the district court correctly construed the claim term “boss” as limited to integral structures based on a clear prosecution disclaimer and that the asserted claims were sufficiently definite under Nautilus, Inc. v. Biosig Instruments, Inc., 572 U.S. 898 (2014). Therefore, the judgment of noninfringement and no indefiniteness was affirmed (Barrette Outdoor Living, Inc. v. Fortress Iron, LP, Nos. 24-1231, 24-1359 (Fed. Cir. Oct. 17, 2025)).

Background. The plaintiff/appellant, Barrette Outdoor Living, Inc., is a U.S.-based manufacturer of fencing and railing systems, producing vinyl, steel, and aluminum products for residential and commercial use. The defendants/cross-appellants, Fortress Iron, LP, and its affiliate Fortress Fence Products, LLC, are Texas-based companies specializing in ornamental metal fences and rail systems. Both companies directly compete in the U.S. fencing market.

Barrette’s asserted patents—U.S. Patent Nos. 8,413,332 (the ’332 patent), 8,413,965 (the ’965 patent), 9,551,164 (the ’164 patent), and 9,963,905 (the ’905 patent)—share a common specification and parent application, U.S. Patent No. 9,151,075 (the ’075 patent). These patents describe fencing assemblies using sliding, pivoting connectors that link vertical pickets to horizontal rails, enabling improved angular adjustment (or “racking”) without the need for screws or bolts. The connectors use “bosses,” “nubs,” or “projections” extending from the connector strip to engage pivot holes in the pickets, thereby forming a fastener-less, yet pivotal, connection.

In 2021, Barrette sued Fortress in the Northern District of Texas, alleging that Fortress’s “Athens Residential” fencing systems infringed the above patents. Fortress denied infringement and counterclaimed for invalidity, arguing that key claim terms were indefinite under 35 U.S.C. § 112.

In its Markman order, the district court construed the terms “boss,” “projection,” and “nub” as interchangeable and limited to integral, fastener-less structures. The court based this interpretation on the specification’s repeated references to “fastener-less but still pivotal” connections and on Barrette’s prosecution history statements distinguishing prior art that used separate pins. The court also rejected Fortress’s indefiniteness challenges to the “sliding” and “causes” limitations, holding that the specification provided sufficient guidance through figures and descriptions.

Following claim construction, Barrette stipulated that it could not prove infringement under the court’s “integral boss” construction, while Fortress stipulated that it could not prove indefiniteness under the court’s interpretation. Final judgment of noninfringement and no indefiniteness was entered. Barrette appealed the noninfringement ruling; Fortress cross-appealed on indefiniteness.

Integral versus fastener-less bosses. On appeal, Barrette argued that the district court erred in construing “boss” as both “integral” and “fastener-less.” The Federal Circuit, per Judge Linn (joined by Chief Judge Moore and Judge Cunningham), agreed that the district court’s “fastener-less” limitation was too narrow but affirmed the finding that “boss” was integral.

The court observed that the patents described two main advantages—fast installation and improved racking ability—but not every advantage must appear in every claim. Citing Phillips v. AWH Corp., 415 F.3d 1303, 1327 (Fed. Cir. 2005), the panel explained that “claims should not be construed to require every advancement disclosed in the specification.” While the specification described fastener-less assemblies as advantageous, it did not clearly disclaim fastener use altogether. Thus, the “fastener-less” feature was not mandatory.

However, the court held that during prosecution of the parent ’075 patent, Barrette unmistakably disclaimed non-integral bosses. In response to a rejection over U.S. Patent Publication No. 2009/0065755 (Sherstad), Barrette had argued that Sherstad’s “pivot pin” structure did not disclose the “claimed integral boss.” This, the panel held, was a clear and unmistakable prosecution disclaimer limiting “boss” to an integral structure.

Prosecution disclaimer. Barrette contended that any disclaimer in the ’075 prosecution should not apply retroactively to the earlier-issued ’332 and ’965 patents. The Federal Circuit disagreed, citing Teva Pharms. USA, Inc. v. Sandoz, Inc., 789 F.3d 1335, 1343 (Fed. Cir. 2015), which allows statements made during prosecution of related patents—whether before or after issuance—to inform claim construction. The panel emphasized that “a statement made during prosecution of related patents may be properly considered in construing a term common to those patents.”

The court also rejected Barrette’s reliance on Ecolab, Inc. v. FMC Corp., 569 F.3d 1335 (Fed. Cir. 2009), and Malvern Panalytical Inc. v. TA Instruments-Waters LLC, 85 F.4th 1365 (Fed. Cir. 2023), which found no disclaimer where applicants had abandoned prior arguments or acquiesced to examiner corrections. Unlike those cases, Barrette never retracted its integral-boss argument or indicated examiner disagreement. Thus, the disclaimer remained effective.

Finally, citing Hakim v. Cannon Avent Group, PLC, 479 F.3d 1313 (Fed. Cir. 2007), the court explained that even though Barrette later canceled the rejected claims and refiled new ones, it could not recapture disclaimed subject matter without clearly notifying the examiner, which it failed to do.

Synonymous terms. The Federal Circuit further held that Barrette could not distinguish between “boss” and “projection” on appeal because it had treated them as synonymous before the district court. Citing Interactive Gift Express, Inc. v. Compuserve Inc., 256 F.3d 1323 (Fed. Cir. 2001), the court found the argument forfeited. Although “nub” and “series of axles” were narrower terms, they were necessarily integral because they depended on the broader “boss” or “projection” language.

The noninfringement finding was affirmed since Barrette had stipulated that Fortress's products lacked integral bosses or projections.

Indefiniteness. Fortress’s cross-appeal challenged the definiteness of the “sliding” terms (“slidably engaged,” “sliding surface,” etc.), arguing that the functional nature of the language made the claim scope unclear. The Federal Circuit disagreed, applying the Nautilus standard and finding that the claims, read with the specification, would “inform, with reasonable certainty, those skilled in the art about the scope of the invention.”

Citing Sonix Tech. Co. v. Publ’ns Int’l, Ltd., 844 F.3d 1370, 1377 (Fed. Cir. 2017), and Nevro Corp. v. Boston Scientific Corp., 955 F.3d 35, 39–40 (Fed. Cir. 2020), the court reasoned that exact mathematical precision was unnecessary. The figures and descriptions—particularly Figures 7C and 7D—adequately demonstrated the sliding mechanism, enabling artisans to understand the claimed relationships.

Fortress also argued that the phrase "pivoting … causes the respective connector to slide" was indefinite because it suggested a strict one-to-one causal relationship. The court rejected this argument, holding that the specification and prosecution history clarified the term's meaning. The language merely described the physical interaction between components, which a skilled artisan could interpret with reasonable certainty.

Thus, the Federal Circuit concluded that the district court’s claim construction and indefiniteness rulings were sound and affirmed the judgments of noninfringement and no invalidity for indefiniteness, with each party bearing its own costs.

The Case is Nos. 24-1231, 24-1359.

Judge: Linn, R.

Attorneys: Tyler Robert Marandola (Duane Morris LLP) for Barrette Outdoor Living, Inc. Paul V. Storm (Foley & Lardner LLP) for Fortress Iron, LP and Fortress Fence Products, LLC.

Companies: Barrette Outdoor Living, Inc.; Fortress Iron, LP; Fortress Fence Products, LLC

Cases: Patent FedCirNews TexasNews