In a decision that serves as a powerful reminder of the enduring impact of the prosecution file wrapper, the U.S. Court of Appeals for the Federal Circuit has affirmed a judgment of non-infringement, binding a patentee to a narrowing statement made years after some of the asserted patents had already issued. The case demonstrates the critical, and sometimes perilous, nature of arguments made to distinguish prior art, even when those arguments fail to win allowance.
The October 17, 2025, precedential opinion in Barrette Outdoor Living, Inc. v. Fortress Iron, LP, Nos. 2024-1231, 2024-1359 (Fed. Cir. 2025), provides exemplary analysis of prosecution history disclaimer, clarifying when an applicant’s statements become a permanent surrender of claim scope and when they might be excused as mere argument.
Background of the Dispute
The case involves patents owned by Barrette Outdoor Living, Inc. (”Barrette”) directed to fencing assemblies. The technology centers on a “sliding pivotal connection” that joins vertical pickets to horizontal rails. This design purportedly offers two main advantages over the prior art: it allows the pickets to “rack” or pivot to a greater degree, and it is “very easy and fast to install” (Slip Op., p. 3).
This quick installation was achieved through connectors featuring “small projections (e.g., bosses)” that fit into holes on the pickets, creating what the specification calls a “fastener-less but still pivotal connection” (p. 3). Some of the asserted patents explicitly claim a “boss”, while another claims a “projection.”
Barrette sued Fortress Iron, LP (”Fortress”), alleging that Fortress’s “Athens Residential” fences infringed four of its patents. The case turned, as patent disputes often do, on claim construction. At the district court, Fortress argued that the term “boss” (and its related terms like “projection”) should be construed as being both fastener-less and integral (i.e., formed as a single piece with the connector). The district court agreed, adopting this narrow construction (pp. 6-7).
This construction was fatal to Barrette’s case, as it conceded that Fortress’s accused products use “non-integral fasteners” (p. 7). Barrette stipulated to a judgment of non-infringement, preserving its right to appeal the claim construction. Fortress cross-appealed, arguing that other claim terms—specifically “sliding” and “causes”—were invalid for indefiniteness.
A Tangled Web: The Patent Family and Prosecution Timeline
A critical element of this case is the relationship between the asserted patents and the timing of the key prosecution event. Barrette asserted four patents: 8,413,332, 8,413,965, 9,551,164, and 9,963,905. All of these “share a common specification and parent application that issued as U.S. Patent No. 9,151,075 (the ‘075 patent’)” (p. 2).
The crucial event—Barrette’s disclaimer regarding “integral” bosses—did not occur during the prosecution of the patents asserted in the lawsuit. Instead, it happened “during the prosecution of the ‘075 patent, but after the ‘332 and ‘965 patents had already issued” (p. 4). This timeline created a central legal question: could a statement made to the patent office in a later application be used to narrow the scope of claims in patents that were already granted? As the Federal Circuit would later confirm, the answer is a resounding yes. This fact pattern underscores the portfolio-wide effect that prosecution arguments can have, reaching backward in time to impact the scope of previously issued patents.
The Court’s Analysis: A Split Decision on Construction
The Federal Circuit’s analysis tackled the claim construction and indefiniteness issues separately. While Barrette won a partial victory on the “fastener-less” limitation, it was the “integral” limitation that proved dispositive.
The “Fastener-less” Construction: A District Court Error
The Federal Circuit disagreed with the district court that the claims required a “fastener-less” connection. The court found that the specification presented multiple advantages, not just one. While the specification praised the “fastener-less” connection for its quick installation, it credited the sliding capability of the connector for the improved racking ability.
Citing its own precedent, the court reiterated that “the fact that a patent asserts that an invention achieves several objectives does not require that each of the claims be construed as limited to structures that are capable of achieving all of the objectives” (p. 9).
Because the improved racking advantage did not depend on a fastener-less connection, the specification’s discussion of that feature was not a “clear and unmistakable” disavowal of all fasteners (pp. 10-11). This part of the district court’s construction was held to be in error.
The “Integral” Construction: A Binding Disclaimer
Barrette’s victory was short-lived. The Federal Circuit affirmed the district court’s construction of “boss” as being “integral.” This construction was based not on the patent’s specification, but on statements Barrette made during the prosecution of the related ‘075 patent.
During that prosecution, the patent examiner rejected claims over a prior art reference, Sherstad. In response, Barrette attempted to distinguish the reference, arguing that Sherstad disclosed “a conventional pivot hole and pivot pin assembly,” and not Barrette’s “slip-together connection with the claimed integral boss” (p. 5).
On appeal, Barrette argued this statement should not be a binding disclaimer, relying on cases where disclaimers were not found after an applicant abandoned an argument rejected by an examiner like 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) (pp. 11-12).
The Federal Circuit found those cases distinguishable, providing a critical clarification:
“Here, although Barrette maintains that the examiner rejected the view that the claims required an integral boss, the examiner disagreed not with Barrette’s characterization of the ‘boss’ term in its own claims but with Barrette’s assessment of the scope of Sherstad’s disclosure” (p. 15).
In essence, Barrette clearly characterized its own invention as having an “integral boss” to distinguish the prior art. The examiner’s disagreement was about the prior art, not Barrette’s characterization of its claims.
Barrette’s statement, therefore, remained a clear clarification of its claim scope. The fact that the argument “proved unavailing does not render it ineffective as a disclaimer” (p. 16).
The Scope of the Disclaimer
The court confirmed that the disclaimer made during the ’075 prosecution was properly applied to the already-issued patents. The court stated plainly that “a statement made during prosecution of related patents may be properly considered in construing a term common to those patents, regardless of whether the statement pre- or post-dates the issuance of the particular patent at issue” (p. 17).
Furthermore, the court rejected Barrette’s attempt to argue that the term “projection” (used in the ’905 patent) was broader than “boss.” The court found this argument forfeited because Barrette had argued the opposite to the district court, where it “urge[d] that a ‘boss’ in the context of the Patents-in-Suit is simply a projection or protrusion” (p. 18). Barrette, the court concluded, “may not argue differently here” (p. 18).
The Indefiniteness Cross-Appeal
The court summarily affirmed the district court’s finding that the terms “sliding” and “causes” were not indefinite. Fortress argued that the specification failed to provide guidance on parameters like the force needed to slide or acceptable levels of friction. The court disagreed, finding that the claims, specification, and figures provided ample context. Quoting precedent, the court noted that an inventor “need not define his invention with mathematical precision in order to comply with the definiteness requirement” (p. 22).
Key Takeaways and Practical Implications
The Barrette decision provides several critical reminders for patent practitioners, litigators, and inventors.
Statements Characterizing the Claims Carry Enduring Weight: The prosecution history of any single patent application can have a lasting and retroactive impact across an entire patent family (i.e., a shared specification). Practitioners must exercise extreme caution with any statement that characterizes the scope of their own claims to distinguish prior art. As this case shows, such statements are likely to be treated as a permanent and binding surrender of scope for all related patents, even those already granted, and even if the argument ultimately fails to persuade the examiner. The key is whether the statement defines the invention, not just what the prior art discloses.
The Nuance of Disclaimer: The court offered a useful test. When an applicant characterizes their own claims to gain allowance, it is likely a binding disclaimer. The examiner must explicitly disagree with the applicant’s characterization of their own claims—not just the prior art—for the disclaimer to potentially be excused.
Litigation Strategy and Forfeiture: Barrette’s case was severely damaged by its own arguments. Arguing at the district court that “boss” and “projection” were synonymous forfeited the ability to argue on appeal that they were different. This highlights the need for a consistent and forward-looking claim construction strategy from the very beginning of a dispute.
Advocacy vs. Surrender: The court distinguished between highlighting one of several advantages (the “fastener-less” feature) and explicitly surrendering scope (the “integral” feature). Practitioners can and should advocate for their inventions by describing their benefits, but they must be vigilant to avoid language that “clearly and unmistakably” limits the claims to only the structure that achieves a particular benefit.
Conclusion
The Federal Circuit affirmed the district court’s judgment. Although the district court erred in limiting the claims to a “fastener-less” design, its “integral” construction was correct. Because Barrette had already stipulated that its products did not meet this “integral” limitation, the judgment of non-infringement was proper.
Barrette v. Fortress Iron reinforces a foundational principle of patent law: what is said during prosecution, especially to distinguish prior art, will be used to define the boundaries of the patent grant. The decision underscores the need for extreme care and strategic foresight in all communications with the patent office, as a single, ill-considered phrase can have portfolio-wide, and case-dispositive, consequences.
Disclaimer: This is provided for informational purposes only and does not constitute legal or financial advice. To the extent there are any opinions in this article, they are the author’s alone and do not represent the beliefs of his firm or clients. The strategies expressed are purely speculation based on publicly available information. The information expressed is subject to change at any time and should be checked for completeness, accuracy and current applicability. For advice, consult a suitably licensed attorney and/or patent professional.