Technology Information Law Blog by Charles Gideon Korrell

Tag: prosecution history disclaimer

  • Barrette Outdoor Living, Inc. v. Fortress Iron, LP: Prosecution Disclaimer in a Later Continuation Can Narrow an Entire Patent Family

    Barrette Outdoor Living, Inc. v. Fortress Iron, LP: Prosecution Disclaimer in a Later Continuation Can Narrow an Entire Patent Family

    On October 17, 2025, the Federal Circuit issued a detailed and consequential opinion in Barrette Outdoor Living, Inc. v. Fortress Iron, LP, affirming a judgment of non-infringement while also affirming the district court’s rejection of indefiniteness challenges. The case provides a clear reminder that arguments made during prosecution of a later-filed continuation application can narrow the scope of earlier-issued patents in the same family, even where those earlier patents were already granted and never amended.

    The decision is especially notable for its careful treatment of prosecution disclaimer across time, its distinction between examiner disagreement and applicant acquiescence, and its application of those principles to claim terms that appear, at least facially, to be broader than the disclaimed language. As Charles Gideon Korrell has observed in other contexts, this opinion underscores that prosecution arguments can be as dangerous as claim amendments, particularly in large patent families with overlapping claim language.

    Background and the Asserted Patents

    Barrette owns four related patents directed to fencing and railing assemblies that use sliding, pivoting connectors to attach pickets to rails. The patents share a common specification and trace back to a common parent application. The asserted patents include U.S. Patent Nos. 8,413,332; 8,413,965; 9,551,164; and 9,963,905. The claims generally recite connectors having “bosses,” “projections,” or similar protruding structures that engage holes in the pickets, allowing the pickets to pivot and slide relative to the rails.

    The accused products, Fortress’s Athens Residential fences, use connectors that employ non-integral fasteners. After claim construction, Barrette stipulated that it could not prove infringement under the district court’s construction, while Fortress stipulated that it could not prove indefiniteness. That procedural posture set the stage for a clean appeal on claim construction and indefiniteness.

    Claim Construction and the “Boss” Terms

    The central dispute on appeal concerned the meaning of “boss,” “projection,” and related terms. The district court construed these terms as limited to integral structures, and further concluded that they were fastener-less. Barrette challenged both aspects of that construction.

    The Federal Circuit agreed with Barrette on one point but not the other. First, the court rejected the district court’s conclusion that the specification clearly and unmistakably disclaimed bosses that use fasteners. Relying on Phillips v. AWH Corp., the court reiterated that patents often describe multiple advantages over the prior art and that claims should not automatically be limited to structures that achieve every disclosed advantage. Here, although the specification emphasized fast installation as one benefit of the invention, it also emphasized improved racking ability, which did not inherently require fastener-less connections. The intrinsic record did not support importing a fastener-less limitation into the claims.

    That conclusion, however, did not save Barrette’s infringement case.

    Prosecution Disclaimer and Integral Structures

    The decisive issue was prosecution disclaimer arising from statements made during prosecution of a later continuation application that issued as the ’075 patent. During that prosecution, the examiner rejected claims over the Sherstad reference, which disclosed a pivot pin assembly. In response, Barrette argued that Sherstad failed to disclose a “slip-together connection with the claimed integral boss,” distinguishing Sherstad’s use of a discrete pin member from Barrette’s claimed structure.

    The Federal Circuit held that this argument constituted a clear and unmistakable disclaimer of non-integral bosses. Importantly, the court rejected Barrette’s attempt to characterize the argument as ambiguous or ineffective simply because the examiner ultimately maintained the rejection and Barrette later canceled the claims. The focus of disclaimer analysis, the court emphasized, is what the applicant said, not whether the argument persuaded the examiner or was strictly necessary to secure allowance.

    The court distinguished Ecolab, Inc. v. FMC Corp. and Malvern Panalytical Inc. v. TA Instruments-Waters LLC, where examiner disagreement and applicant acquiescence rendered earlier narrowing arguments ambiguous. Here, the examiner did not disagree with Barrette’s characterization of its own claims. Rather, the examiner disagreed with Barrette’s characterization of the prior art. Nothing in the prosecution history suggested that Barrette’s description of its own invention was mistaken or withdrawn.

    As Charles Gideon Korrell notes, this distinction is critical. Examiner disagreement with claim scope may neutralize a disclaimer, but examiner disagreement with an applicant’s reading of the prior art does not.

    Temporal Reach of Disclaimer Across the Family

    Barrette also argued that statements made during prosecution of the later-filed ’075 patent could not limit the scope of earlier-issued patents such as the ’332 and ’965 patents. The Federal Circuit squarely rejected that argument, citing Teva Pharmaceuticals USA, Inc. v. Sandoz, Inc. for the proposition that statements made during prosecution of related patents may be considered in construing common claim terms, regardless of whether the statements pre- or post-date issuance of the patent at issue.

    This aspect of the opinion reinforces a recurring theme in Federal Circuit jurisprudence: patent families rise and fall together when claim language and specifications are shared. Strategic arguments in one application can echo backward in time.

    Extending the Disclaimer to Related Terms

    Barrette attempted to limit the damage by arguing that even if “boss” was limited to integral structures, other claim terms—such as “projection,” “nub,” and “series of axles”—should retain broader meanings. The court was unpersuaded.

    As to “projection,” the court found forfeiture. Barrette had repeatedly argued before the district court that “boss” and “projection” were commensurate in scope, even characterizing “projection” limitations as “boss” terms in its Markman submissions. Having taken that position below, Barrette could not reverse course on appeal.

    With respect to “nub” and “series of axles,” the court acknowledged that these terms were narrower than “boss,” but concluded that narrowing did not help Barrette. If the broader term was limited to integral structures, then the narrower terms necessarily were as well. Thus, even assuming some error in the district court’s interchangeable-use analysis, the outcome remained the same.

    Indefiniteness: Sliding and “Causes”

    On cross-appeal, Fortress challenged the district court’s rejection of its indefiniteness arguments. Fortress contended that the “sliding” terms were functional and ambiguous, and that the claims failed to specify parameters such as force, friction, or degree of motion.

    The Federal Circuit disagreed. Applying Nautilus, Inc. v. Biosig Instruments, Inc. and Sonix Technology Co. v. Publications International, Ltd., the court emphasized that definiteness requires reasonable certainty, not mathematical precision. The claims and specification provided sufficient guidance by describing how pivoting of the pickets causes the connector to slide along the rail, and by illustrating those interactions in multiple figures.

    Similarly, the court rejected Fortress’s argument that the term “causes” was indefinite because not every act of pivoting necessarily resulted in sliding. The court held that Barrette’s explanation during prosecution merely clarified the causal relationship in context, and that a skilled artisan could ascertain the scope of the term with reasonable certainty.

    Practical Takeaways

    The Federal Circuit’s decision delivers several practical lessons.

    First, prosecution disclaimer remains a potent doctrine, and it applies with full force to arguments, not just amendments. Second, disclaimers can propagate across an entire patent family, even retroactively affecting earlier-issued patents. Third, examiner disagreement only matters if it clearly signals that the applicant’s narrowing characterization was incorrect and accepted as such by the applicant.

    Charles Gideon Korrell believes that this case will encourage applicants to think more carefully about whether an argument is truly worth making in a continuation application. In many cases, the safer course may be to amend claims explicitly or to draft continuation claims that clearly delineate different scopes, rather than relying on argumentative distinctions that may later become shackles.

    In the end, Barrette lost not because its invention lacked merit, but because its own words during prosecution narrowed its claims beyond repair. As patent families continue to grow larger and more complex, this decision serves as a sharp reminder: every prosecution argument is a potential legacy.

    By Charles Gideon Korrell

  • Focus Prods v. Kartri Sales: When Restriction Practice Becomes Prosecution History Disclaimer

    Focus Prods v. Kartri Sales: When Restriction Practice Becomes Prosecution History Disclaimer

    The Federal Circuit’s decision in Focus Products Group International, LLC v. Kartri Sales Co., Inc. delivers a wide-ranging opinion that touches nearly every corner of intellectual property litigation: venue after TC Heartland, prosecution history disclaimer, multi-defendant appellate waiver, trademark standing, trade dress functionality, willfulness, and fee shifting. But at its core, the case stands as a cautionary tale about examiner-driven restriction practice and the long shadow it can cast over claim scope years later.

    The dispute arose from “hookless” shower curtains—products designed to hang directly on a shower rod using integrated rings with slits, eliminating the need for separate hooks. Focus Products and its related entities asserted three related utility patents, along with trademark and trade dress rights, against Kartri Sales Co. and its supplier Marquis Mills. After years of litigation in the Southern District of New York, the district court largely sided with Focus, entering summary judgment of patent infringement, finding trademark and trade dress infringement, determining willfulness, and awarding enhanced damages and attorneys’ fees.

    On appeal, the Federal Circuit affirmed some findings, reversed others, vacated substantial portions of the judgment, and remanded for further proceedings. The result was a sharply divided outcome between the two defendants and a detailed roadmap of how procedural and prosecution decisions can dictate substantive outcomes.

    Venue and the Cost of Delay After TC Heartland

    The opinion first addresses venue, rejecting the defendants’ attempt to escape the Southern District of New York under TC Heartland. Although TC Heartland made venue objections newly available, the Federal Circuit emphasized that such objections must still be raised seasonably. Here, the defendants waited nearly four months after TC Heartland—while continuing discovery and depositions—before objecting.

    The court distinguished earlier cases where venue objections were preserved promptly and litigation remained in its early stages. The lesson is straightforward: TC Heartland did not create an open-ended escape hatch. Delay and continued participation in litigation can forfeit venue challenges, even when the law changes mid-case.

    Restriction, Election, and the Birth of Disclaimer

    The most consequential portion of the decision concerns the ’248 and ’609 patents and the meaning of “ring.” During prosecution of the original application, the examiner issued a restriction requirement identifying multiple patentably distinct species. One species included rings with projections or fingers extending from the outer circumference; another species included rings with a flat upper edge.

    The applicant elected the projected-edge species and did not traverse the examiner’s characterization. When the applicant later attempted to include claims expressly reciting a flat upper edge, the examiner withdrew those claims as drawn to a non-elected species. The applicant again did not object and proceeded to allowance.

    Years later, Focus argued that the issued claims were broad enough to encompass flat-topped rings. The Federal Circuit disagreed. Reading the prosecution history as a whole, the court held that the patentee had clearly and unmistakably disclaimed rings with flat upper edges for the ’248 and ’609 patents by acquiescing in the examiner’s species demarcation.

    This was not a case of ambiguous silence. The examiner repeatedly enforced the boundary between species, and the applicant repeatedly accepted it. As the court explained, cooperation with the examiner’s demand to exclude a species—without traversal—can operate as an affirmative disclaimer, even absent express words of surrender.

    The continuation history reinforced that conclusion. When prosecuting the later ’088 patent, the applicant distinguished the earlier patents by adding a “flat upper edge” limitation to overcome a double patenting rejection. That amendment only made sense if the earlier patents did not already cover flat-topped rings. The Federal Circuit treated that prosecution history as confirming the narrowed scope of the earlier claims.

    Because the accused products used flat-topped rings, the court reversed the infringement findings for the ’248 and ’609 patents as to Marquis.

    The ’088 Patent and the Limits of Summary Judgment

    The outcome for the ’088 patent was more nuanced. The Federal Circuit agreed with the district court’s construction of “projecting edge” as “an edge that projects from the outer circumference of the ring.” But it found the infringement analysis insufficiently explained.

    The district court had concluded that a portion of the accused ring constituted a projecting edge, yet failed to articulate where the ring’s outer circumference ended and the projecting edge began. The Federal Circuit noted that the accused rings closely resembled embodiments in the specification that lacked any projecting edge at all.

    Without a clear analytical framework distinguishing circumference from projection, summary judgment could not stand. The court vacated the ’088 patent infringement finding for Marquis and remanded for a more rigorous analysis tied to the intrinsic record.

    Appellate Waiver and Divergent Outcomes

    One of the more unusual aspects of the case was the divergent outcome between Kartri and Marquis, despite their products being essentially identical. That divergence stemmed not from technical differences, but from appellate briefing strategy.

    The defendants filed separate opening briefs that attempted to divide issues between them. Marquis fully developed the patent arguments; Kartri devoted barely a page to them. When challenged, both defendants disclaimed any intent to rely on each other’s arguments—accepting the risk of waiver.

    The Federal Circuit took them at their word. Marquis preserved and won on the key patent issues. Kartri, by contrast, waived its patent non-infringement arguments through underdevelopment. As a result, infringement findings were reversed or vacated for Marquis, but largely affirmed for Kartri.

    This portion of the opinion is a stark reminder that appellate courts will not rescue parties from strategic choices about briefing. Identical facts do not guarantee identical outcomes when arguments are waived.

    Trademarks, Standing, and Ownership Proof

    The court also dismantled the district court’s finding that Focus had standing to assert the EZ ON trademark. Focus relied on a 2012 licensing agreement to show ownership, but the Federal Circuit carefully parsed the contract and found no transfer of trademark ownership before suit was filed.

    The agreement licensed HOOKLESS®, not EZ ON. Provisions concerning “Licensed Products” did not establish mark ownership, and a clause discussing assignment of later-developed intellectual property did not plausibly apply to trademarks through “reduction to practice.” Actual assignment of the EZ ON mark occurred years after the lawsuit began.

    Because standing must exist at filing, the Federal Circuit reversed the EZ ON trademark infringement finding outright.

    The court also vacated the HOOKLESS® trademark infringement finding, concluding that the district court’s likelihood-of-confusion analysis improperly focused on product similarity rather than mark-to-mark comparison in the marketplace context.

    Trade Dress and TrafFix Revisited

    Trade dress fared no better. The district court found Focus’s asserted trade dress non-functional based on its “neat and orderly” appearance and the availability of alternative designs. The Federal Circuit held that analysis incomplete under TrafFix.

    Where an expired utility patent claims the same features asserted as trade dress, functionality is strongly presumed. The district court failed to meaningfully compare the claimed trade dress elements with the features claimed in Focus’s expired patent. Without that comparison, Focus could not meet its burden to prove non-functionality.

    The trade dress infringement finding was vacated and remanded for proper application of TrafFix.

    Willfulness, Fees, and the Unraveling of Enhancements

    With large portions of the infringement judgment undone, the Federal Circuit also vacated findings of willfulness and the resulting enhanced damages. Notice of patent rights alone was insufficient, particularly where defendants articulated consistent non-infringement positions grounded in prosecution history. Similarly, trade dress willfulness could not predate notice of the asserted trade dress.

    The attorneys’ fee award was likewise vacated. While the district court did not abuse its discretion in deeming the case exceptional, the fee calculation failed to separate compensable work from claims on which Focus no longer prevailed.

    Takeaways

    This decision reinforces several practical lessons. Restriction requirements and elections matter, especially when untraversed. Acquiescence can shape claim scope just as powerfully as express disclaimer. Continuation practice can lock in those boundaries rather than erase them. Appellate briefing choices can determine winners and losers independent of product facts. And trademark and trade dress claims demand disciplined proof of ownership and non-functionality.

    As Charles Gideon Korrell notes, restriction practice is often treated as a procedural inconvenience, but Focus Products shows it can become substantive destiny. Charles Gideon Korrell believes that patent prosecutors should treat elections with the same care as claim amendments, assuming every concession may later be read as intentional surrender. And Charles Gideon Korrell observes that this case is also a reminder that appellate courts enforce waiver rules strictly, even when doing so leads to asymmetrical results.

    The Federal Circuit’s opinion is long, detailed, and unsparing. It rewards precision and punishes shortcuts—both in prosecution and in litigation.

    By Charles Gideon Korrell

  • Top Brand LLC v. Cozy Comfort Company LLC: Federal Circuit Reverses $18.5M Infringement Verdict Based on Design Patent Disclaimer and Weak Trademark Use

    Top Brand LLC v. Cozy Comfort Company LLC: Federal Circuit Reverses $18.5M Infringement Verdict Based on Design Patent Disclaimer and Weak Trademark Use

    In a significant ruling that underscores the Federal Circuit’s evolving approach to design patent claim scope and the evidentiary burden in trademark cases, the court in Top Brand LLC v. Cozy Comfort Company LLC, No. 24-2191 (Fed. Cir. July 17, 2025), reversed a jury’s $18.5 million verdict for design patent and trademark infringement. Charles Gideon Korrell sees this decision to be noteworthy for three key holdings: (1) prosecution history disclaimer applies to design patents; (2) the accused product was within the surrendered scope and therefore could not infringe; and (3) the evidence of trademark infringement failed under the Lanham Act’s likelihood-of-confusion standard.

    Background: Oversized Hoodies and the D788 Design Patent

    Cozy Comfort markets a popular oversized wearable blanket called “The Comfy,” protected by U.S. Design Patent No. D859,788 (“D788 patent”) and two federal trademark registrations for “THE COMFY.” Top Brand, through various Amazon storefronts and other e-commerce platforms, sells similar products under the brands “Tirrinia” and “Catalonia.”

    In district court, Cozy Comfort alleged that Top Brand’s seven product lines infringed its D788 design patent and trademarks. Charles Gideon Korrell points out that the jury found infringement of both, awarding $15.4 million in disgorged profits for the design patent claim and $3.08 million for trademark infringement. The district court denied Top Brand’s motion for judgment as a matter of law (“JMOL”), and Top Brand appealed.

    Design Patent: The Federal Circuit Applies Prosecution History Disclaimer

    Judge Dyk, writing for the unanimous panel, held that the district court erred in failing to apply prosecution history disclaimer to the design patent. Although the doctrine has long applied to utility patents, this marks a definitive and precedential statement that it applies with equal force to design patents.

    The court relied on Pacific Coast Marine Windshields Ltd. v. Malibu Boats, LLC, 739 F.3d 694 (Fed. Cir. 2014), which recognized disclaimer by amendment in a design patent context, and extended the rationale to disclaimer by argument. The court emphasized that “[i]t would be contrary to the very purpose of design patent prosecution to allow the patentee to make arguments in litigation contrary to the representations which led to the grant of the patent.”

    Charles Gideon Korrell notes that Cozy Comfort had narrowed the scope of the D788 patent during prosecution to overcome prior art (specifically, the White reference) by distinguishing its design based on four features:

    1. A marsupial pocket that was narrow and square-like,
    2. Pocket placement beneath the armholes,
    3. A downward-sloping bottom hemline,
    4. A different armscye-pouch vertical alignment.

    Because the accused products from Top Brand mirrored the features found in the disclaimed White reference—especially in the width and shape of the pocket and the upward hemline—the court held that no reasonable jury could have found infringement under the proper claim construction.

    This decision reaffirms Egyptian Goddess, Inc. v. Swisa, Inc., 543 F.3d 665 (Fed. Cir. 2008) (en banc), and illustrates how prosecution statements that “distinguish” the claimed design can limit scope in infringement proceedings.

    Trademark: Descriptive Use of “Comfy” Not Likely to Confuse

    The Federal Circuit also reversed the jury’s trademark infringement verdict, finding insufficient evidence under the Ninth Circuit’s Sleekcraft factors. Most notably, the court concluded:

    • “THE COMFY” is a weak mark, given the descriptive nature of “comfy” for wearable blankets.
    • Top Brand never used the full phrase “THE COMFY” but instead used the term “Comfy” descriptively on a drop-down menu that also included generic terms like “Mermaid Tail Blankets” and “Snuggly.”
    • There was no evidence that “Comfy” functioned as a source identifier or was used with secondary meaning.
    • Alleged instances of actual confusion—such as customer questions on Amazon asking whether a Tirrinia product was “the real Comfy”—were de minimis and not clearly attributable to Top Brand’s conduct.

    The court emphasized that without use of the protected mark as a source identifier, even descriptively similar terms cannot give rise to actionable trademark infringement. It cited KP Permanent Make-Up, Inc. v. Lasting Impression I, Inc., 543 U.S. 111 (2004), and Booking.com B.V., 591 U.S. 549 (2020), to underscore the narrow scope of rights afforded to descriptive marks absent secondary meaning.

    Strategic Implications

    This decision contains several important takeaways:

    1. Design Patentees Must Live With Prosecution History: Just as in utility patents, representations made to the USPTO can and will be used to limit design patent claim scope. This ruling is a cautionary tale for patent prosecutors and litigators alike.
    2. Design Patent Scope Is Exceptionally Narrow: The court reiterated that design patents protect only the drawings shown and are easily limited by disclaimer. The “overall impression” test from Gorham and Egyptian Goddess remains the standard, but only within properly construed boundaries.
    3. Trademark Claims Require Real Evidence: The bar for proving likelihood of confusion under the Sleekcraft factors remains high. Descriptive terms like “comfy” cannot be monopolized without clear evidence of secondary meaning and source-identifying use.
    4. No Need to Reach Invalidity: Since the court reversed the infringement findings, it declined to address the validity of the D788 patent. This follows CloudofChange, LLC v. NCR Corp., 123 F.4th 1333 (Fed. Cir. 2024), and Cardinal Chemical Co. v. Morton Int’l, Inc., 508 U.S. 83 (1993), reinforcing that courts need not reach invalidity if it is conditionally abandoned and no longer relevant to the outcome.

    Charles Gideon Korrell believes this decision will have ripple effects in how district courts handle claim construction in design patent cases—especially when the patentee has walked a fine line during prosecution. It also serves as a warning against asserting weak trademark claims built on descriptive or generic terms without strong supporting evidence.

    By Charles Gideon Korrell