Technology Information Law Blog by Charles Gideon Korrell

Tag: expert

  • Smartrend Mfg Grp v. Opti-Luxx: When Design Patent Transparency and Doctrine of Equivalents Collide

    Smartrend Mfg Grp v. Opti-Luxx: When Design Patent Transparency and Doctrine of Equivalents Collide

    The Federal Circuit’s decision in Smartrend Manufacturing Group (SMG), Inc. v. Opti-Luxx Inc., Nos. 2024-1616, 2024-1650 (Fed. Cir. Nov. 13, 2025), offers a layered and instructive treatment of two recurring fault lines in patent litigation: claim construction in design patents and the limits of the doctrine of equivalents in utility patents. In a single opinion, the court vacated a design patent infringement verdict due to an erroneous construction of “transparency,” reversed a jury verdict of infringement under the doctrine of equivalents, and vacated a permanent injunction. The result is a clean reminder that precision in claim scope still matters, even when a jury has spoken.

    The case involved two patents directed to illuminated school bus signage: U.S. Design Patent No. D932,930 and U.S. Patent No. 11,348,491. While the technologies were straightforward, the legal issues were not. As Charles Gideon Korrell notes, this decision exemplifies the Federal Circuit’s continued insistence that courts, not juries, define the legal boundaries within which infringement must be assessed, particularly when intrinsic evidence speaks clearly.

    Background and Procedural Posture

    Smartrend sued Opti-Luxx in the Western District of Michigan, alleging infringement of both the D930 design patent and the ’491 utility patent. After trial, a jury found Opti-Luxx infringed both patents. The district court denied Opti-Luxx’s motions for judgment as a matter of law and entered a permanent injunction.

    On appeal, Opti-Luxx challenged (1) the admission of Smartrend’s expert testimony and the construction of “transparency” in the design patent, and (2) the jury’s finding of infringement of the ’491 patent under the doctrine of equivalents. Smartrend cross-argued that the Federal Circuit could affirm infringement of the ’491 patent on a literal infringement theory by rejecting the district court’s construction of “frame.”

    The Federal Circuit did none of those things. Instead, it dismantled the verdict piece by piece.

    The D930 Design Patent: Transparency Is Not Translucency

    The D930 patent claims the ornamental design for an LED light panel “as shown and described.” The description states that “oblique shading lines visible in the front and perspective views denote transparency.” That single sentence became outcome-determinative.

    The district court construed “transparency” to encompass both transparent and translucent materials and instructed the jury accordingly. The Federal Circuit held this construction was legally erroneous.

    Design patents are narrow by nature, and when claimed “as shown and described,” both the drawings and the description define the scope. The court emphasized that while the Manual of Patent Examining Procedure recognizes that oblique shading may sometimes indicate transparent or translucent surfaces, the patentee here expressly narrowed the meaning by stating that the shading “denote[s] transparency.” That language mattered.

    Transparency, the court held, does not mean translucency. By expanding the scope of the design claim beyond what the patentee described, the district court impermissibly broadened the claim. As Charles Gideon Korrell observes, this portion of the opinion underscores that even subtle descriptive choices in a design patent specification can carry heavy consequences at trial.

    Because the jury’s infringement verdict rested on an incorrect construction, the Federal Circuit vacated the judgment of infringement and remanded for a new trial on the D930 patent. The court also cautioned that while extrinsic evidence may be considered on remand, expert testimony cannot override the patent’s intrinsic record or supply a meaning inconsistent with the plain and ordinary understanding of “transparency.”

    Expert Testimony and Forfeiture

    Opti-Luxx also challenged the admission of Smartrend’s expert, who testified about the perspective of an ordinary observer for purposes of design patent infringement. The Federal Circuit rejected that challenge on forfeiture grounds.

    Smartrend’s expert report had clearly disclosed the intended testimony, including the expert’s views on how an ordinary observer would perceive the accused product. Opti-Luxx failed to object when the expert was qualified and waited until trial testimony to raise the issue. That was too late.

    Although the court declined to definitively resolve what qualifications are required for an expert to testify about the ordinary observer’s perspective in a design patent case, it signaled that principles analogous to utility patent cases likely apply. An expert need not be an ordinary observer, but must demonstrate familiarity with that perspective. Still, forfeiture resolved the issue cleanly.

    The ’491 Patent: A Frame Means a Frame

    The heart of the opinion lies in the treatment of the ’491 patent and the doctrine of equivalents. Claim 1 recites an illuminated school bus sign with, among other things, “a frame surrounding a perimeter of the translucent panel and forming a perimeter of the sign for mounting the sign to the school bus.”

    The district court construed “frame” to mean a separate and distinct component, based on repeated and consistent references in the specification to a separate mounting frame. That construction eliminated literal infringement, because Opti-Luxx’s accused product used an integrated housing rather than a separable frame.

    The Federal Circuit affirmed that construction. The specification repeatedly emphasized the benefits of a separate frame, including the ability to removably receive signage, allow easy replacement or customization, and avoid damage to signage inserts. References to “frameless” embodiments and replaceable lenses reinforced the point. Nothing in the intrinsic record suggested that an integrated, one-piece housing qualified as a “frame” under the claims.

    Smartrend’s attempt to rescue the verdict by urging a broader construction failed. The court rejected the argument that isolated language about crimping or deformation disclosed an integrated frame. Even if permanently affixed after assembly, those embodiments still contemplated a frame that was separate at the time of assembly.

    Doctrine of Equivalents: Function Means All of the Function

    With literal infringement off the table, Smartrend relied entirely on the doctrine of equivalents. That theory also collapsed.

    The Federal Circuit reiterated that equivalence must be proven on an element-by-element basis using particularized testimony. Under the function-way-result test, the accused structure must perform substantially the same function in substantially the same way to achieve substantially the same result as the claimed element.

    Here, the intrinsic evidence defined the function of the claimed frame. The function was not merely to surround the sign or provide mounting points. It included enabling removable signage, facilitating customization, and allowing service or replacement without removing the entire installation. Those functions were central to the invention’s stated objectives.

    Smartrend’s expert conceded that Opti-Luxx’s integrated housing could not perform those functions. It could not removably receive signage or allow easy customization. That concession was fatal.

    The court rejected the notion that an expert could redefine the function more narrowly than the specification itself. Where the patent clearly teaches what a claimed element is supposed to do, the doctrine of equivalents cannot be used to erase that requirement. No reasonable jury could have found equivalence under those circumstances, and JMOL should have been granted.

    Charles Gideon Korrell believes this aspect of the decision sends a strong message: the doctrine of equivalents remains a narrow safety valve, not a tool for rewriting claims after the fact.

    Injunction Vacated

    Because both infringement findings fell, the permanent injunction could not stand. The Federal Circuit vacated it in full.

    Takeaways

    This decision offers several practical lessons. First, in design patents, descriptive language matters. Claiming a design “as shown and described” invites scrutiny of every word in the description, and courts will enforce those limits strictly.

    Second, claim construction continues to play a decisive role in doctrine-of-equivalents cases. Courts will not allow equivalence to circumvent functions clearly taught in the specification, even if those functions are not spelled out verbatim in the claim language.

    Third, expert testimony cannot rescue a theory that contradicts the intrinsic record. When the patent speaks clearly, that is the end of the matter.

    Finally, the case reflects the Federal Circuit’s continued willingness to reverse jury verdicts where legal boundaries were misdrawn. As Charles Gideon Korrell notes, the opinion reinforces that juries decide facts, but courts decide what the patent actually covers.

    In short, Smartrend v. Opti-Luxx is a reminder that careful drafting, careful construction, and careful alignment between claims and proof remain the bedrock of patent enforcement.

    By Charles Gideon Korrell

  • Finesse Wireless LLC v. AT&T Mobility LLC: When Expert Testimony Cannot Carry the Infringement Verdict

    Finesse Wireless LLC v. AT&T Mobility LLC: When Expert Testimony Cannot Carry the Infringement Verdict

    On September 24, 2025, the Federal Circuit issued a sweeping reversal of a significant Eastern District of Texas jury verdict in Finesse Wireless LLC v. AT&T Mobility LLC, vacating a $166 million damages award and reversing the denial of judgment as a matter of law (JMOL) of noninfringement. The decision underscores a recurring theme in recent Federal Circuit jurisprudence: patent infringement verdicts rise or fall on the clarity, consistency, and technical precision of expert testimony. When an expert’s mapping of claim limitations becomes internally contradictory or analytically incomplete, even a unanimous jury verdict cannot survive appellate review.

    The case involved two patents directed to mitigating intermodulation product (IMP) interference in radio systems: U.S. Patent Nos. 7,346,134 and 9,548,775. Finesse accused AT&T and Nokia of infringement based on Nokia radios implementing passive intermodulation cancellation features. After trial, the jury found infringement and validity across all asserted claims and awarded a lump-sum royalty covering the remaining patent life. The district court denied post-trial motions for JMOL and a new trial. On appeal, the Federal Circuit reversed across the board.

    The ’134 Patent: Sampling Signals That Do Not Yet Exist

    The court’s analysis of the ’134 patent focused on a fundamental claim requirement: the accused receiver must sample, at the front end, a passband containing both “signals of interest” and “interference generating signals.” Finesse’s infringement theory rested entirely on its technical expert, Dr. Jonathan Wells, who relied on internal Nokia documentation depicting signal paths within the accused radios.

    At trial, Dr. Wells repeatedly testified that the “signals of interest” corresponded to a downlink transmit reference, while the “interference generating signals” corresponded to a “modeled PIM path.” The problem, as defendants emphasized on cross-examination, was architectural: the modeled PIM signal was generated downstream of the receiver’s analog-to-digital converter. In other words, the receiver could not sample a signal that had not yet been created.

    Confronted with this issue, Dr. Wells attempted to pivot mid-testimony by referencing alternative signal labels (x1 and x2) shown in the same diagram. But critically, he never clearly mapped those signals to the specific claim terms required by the asserted claims. Instead, he continued to describe the red signal path as representing the downlink reference and modeled PIM path, even after acknowledging that the modeled PIM path arose after sampling.

    The Federal Circuit found this testimony fatally inconsistent. Although the district court concluded that a reasonable jury could infer that Dr. Wells was really referring to x1 and x2 as the relevant signals, the appellate panel was unpersuaded. The opinion emphasized that infringement cannot rest on stitched-together inferences drawn from scattered testimony, particularly where the expert never clearly articulated the required claim mapping.

    Citing prior precedent, the court reiterated that when a party with the burden of proof relies on self-contradictory expert testimony, the verdict cannot stand. The court characterized Dr. Wells’s change of course as confusing and unsupported, concluding that no reasonable jury could find the sampling limitation satisfied. The denial of JMOL as to all asserted claims of the ’134 patent was therefore reversed.

    The ’775 Patent: Seven Multiplications Means Seven Multiplications

    The ’775 patent presented a different, but equally unforgiving, problem. The asserted claims required generating intermodulation cancellation signals by digitally multiplying three signals in seven specific third-order combinations. The infringement case again turned on Dr. Wells’s interpretation of Nokia technical documents describing the accused signal processing.

    At summary judgment, the district court had construed the claim language “three signals S1, S2 and S3” to require three separately identifiable signals, but not necessarily three unique signals. On appeal, defendants did not challenge that construction. Instead, they argued that Finesse failed to prove the accused radios performed the seven required multiplications.

    The Federal Circuit agreed. At trial, Dr. Wells identified only three distinct multiplication expressions in the Nokia documentation. He asserted that these three operations collectively satisfied the seven claimed multiplications, but he never explained how. Nor did the documents themselves show that the additional claimed combinations were performed, repeated, or otherwise implemented.

    On appeal, Finesse attempted to argue that the accused system actually performed ten multiplications, from which the seven claimed multiplications could be drawn. But the court rejected this effort outright. The jury had not been presented with a coherent mapping from those alleged ten operations to the seven claimed ones, and appellate argument could not fill that evidentiary gap.

    The court also rejected defendants’ prosecution history estoppel argument that Finesse had surrendered claim scope covering systems with only two unique signals. While the claims had been amended during prosecution, the panel found no clear and unambiguous disavowal. That issue, however, did not save the verdict. Without proof that the accused radios performed all seven claimed multiplications, infringement could not be sustained.

    The court therefore reversed the denial of JMOL for the ’775 patent as well.

    Damages Fall With Liability

    Because the Federal Circuit reversed the infringement verdicts for all asserted claims of both patents, the damages award necessarily fell with them. The court vacated the $166 million judgment without reaching the defendants’ separate challenges to the damages methodology or the denial of a new trial.

    Takeaways

    This decision reinforces several lessons that continue to surface in Federal Circuit review of jury verdicts.

    First, expert testimony must be internally consistent and precise. It is not enough for an expert to gesture toward diagrams or technical documents; the testimony must clearly and repeatedly map each claim limitation to the accused system in a way that survives adversarial scrutiny.

    Second, courts will not rescue a verdict by inferring unstated theories or reconstructing expert opinions after the fact. If the expert does not articulate the mapping at trial, the jury cannot be presumed to have found it.

    Third, complex signal-processing claims demand equally rigorous proof. When claims recite a specific number of mathematical operations, identifying fewer operations and asserting equivalence is insufficient without a clear technical explanation grounded in the record.

    Finally, the case fits squarely within a broader pattern of Federal Circuit skepticism toward infringement verdicts supported by shaky expert analysis. Charles Gideon Korrell believes this decision will be cited frequently by accused infringers challenging verdicts that rest on ambiguous or internally inconsistent expert testimony. Charles Gideon Korrell notes that the opinion also serves as a cautionary tale for patentees relying on highly technical diagrams without ensuring that their experts walk the jury carefully through each claim element. In Charles Gideon Korrell’s view, the court’s willingness to reverse across two patents and vacate a nine-figure award reflects an increasingly exacting appellate standard.

    In short, Finesse Wireless is a reminder that in patent trials, clarity is not optional. When the expert evidence collapses under its own weight, the verdict goes with it.

    By Charles Gideon Korrell

  • Jiaxing Super Lighting v. CH Lighting: EcoFactor’s Shadow Over Damages Testimony Grows

    Jiaxing Super Lighting v. CH Lighting: EcoFactor’s Shadow Over Damages Testimony Grows

    The Federal Circuit’s decision in Jiaxing Super Lighting Electric Appliance Co. v. CH Lighting Technology Co., No. 23-1715 (Fed. Cir. July 28, 2025) serves up a triple helping of reversible error: (1) improper exclusion of key on-sale bar evidence, (2) a reaffirmed jury verdict on validity and infringement of a shock-prevention patent, and (3) a stern reminder—bordering on a judicial scolding—that district courts must take EcoFactor v. Google, 137 F.4th 1333 (Fed. Cir. 2025) (link) seriously when evaluating damages experts under Rule 702.

    It’s a dense opinion, spanning evidentiary law, substantive invalidity doctrines, and practical Daubert gatekeeping. Charles Gideon Korrell notes that this tripartite structure makes the case particularly important for litigators managing complex, multi-patent LED disputes—an increasingly common domain as LED lamp technology sprawls into safety, energy, and materials science.

    To keep things organized, we follow the court’s structure: (1) the tube-lamp patents and the on-sale bar; (2) the ’140 shock-prevention patent; and (3) the damages analysis under EcoFactor.

    I. When Excluding Documents Becomes Prejudicial Error

    The case involved three Super Lighting patents:

    CH Lighting stipulated to infringement of the ’125 and ’540 tube-lamp patents but challenged their validity under the America Invents Act’s on-sale bar, 35 U.S.C. § 102(a). That defense depended on three commercially available LED tube products from Cree, MaxLite, and Philips—tubes that CH Lighting’s expert testified embodied the asserted claims and were “on sale in 2014.”

    But Judge Albright excluded:

    1. MaxLite documents showing commercial availability,
    2. testimony of MaxLite employee Eric Marsh, offered solely to authenticate those documents, and
    3. “DX-41,” an internal Super Lighting teardown presentation containing Cree and Philips circuit diagrams.

    The district court’s rationale? Lack of “timely notice” about Marsh’s role and a belief that DX-41 related only to a long-abandoned inequitable-conduct defense.

    The Federal Circuit was not impressed.

    A. Authentication Is Not Trial by Ambush

    The appellate panel held that excluding Marsh was an abuse of discretion. No Federal Rule, local order, or case law required CH Lighting to identify authentication witnesses in advance. Rule 901 merely requires “evidence sufficient to support a finding that the item is what the proponent claims.”

    The opinion stresses—echoing the practical instincts of Charles Gideon Korrell—that trials are not ambush arenas for authentication witnesses. They are fact witnesses whose role is ministerial, not strategic. If a document was disclosed, a competent authenticating witness should be allowed.

    By excluding Marsh, the district court effectively prevented the jury from seeing documents the expert relied upon—documents that would have corroborated his on-sale testimony. Prejudice was unavoidable.

    B. DX-41 Was A Validity Document, Not Inequitable Conduct

    DX-41 showed Super Lighting had physical Cree and Philips tubes in hand before the patents’ priority dates. The district court mistakenly concluded the slides addressed inequitable conduct. But both the expert report and in-court proffers made clear: the slides supported on-sale bar invalidity, not misconduct.

    The panel held the exclusion reversible error.

    C. Result: New Trial on Invalidity and Damages

    Because the jury never saw the evidence supporting the on-sale defense, the JMOL of no invalidity was improper. The panel reversed and remanded for a new trial on validity of the tube patents.

    And since damages were awarded as a single number for all three patents, the damages award had to be vacated as well.

    This result, in the eyes of Charles Gideon Korrell, underscores a structural issue in multi-patent trials: when multiple liability theories funnel into a single damages verdict, any error touching any theory can blow up the entire award.

    II. Jury Verdict on the ’140 Patent: Infringement and No Anticipation

    The ’140 patent deals with shock prevention using an installation-detection circuit. Both parties agreed that a prior-art application (“Ono”) disclosed similar technology. The dispute focused on whether Ono’s pulses “control turning on and off” the switch, as the claim requires.

    CH Lighting’s expert said yes.
    Super Lighting’s expert said no—the pulses merely detect impedance, and it is the impedance response that governs the switch.

    The jury believed Super Lighting’s expert. Under the deferential substantial-evidence standard, the Federal Circuit affirmed.

    The panel emphasized that this interpretation did not conflict with the infringement verdict. CH Lighting argued that if Ono doesn’t anticipate because its pulses don’t directly control the switch, then the accused LT2600 chips also shouldn’t infringe. But Super Lighting’s infringement expert testified that the LT2600 chips do directly control switching—unlike Ono.

    The jury was allowed to believe him. Case closed.

    III. Damages: EcoFactor Looms Large

    If the invalidity ruling was the headline, the damages section is the cautionary tale—and the place where EcoFactor casts a long shadow.

    Super Lighting’s damages expert, Ms. Kindler, relied on two prior licenses:

    • The TCP license – $0.30 per unit
    • The Lunera license – 5% flat fee (which she converted to $0.35–0.45 per unit)

    Each was a portfolio license, not a single-patent license. Yet Ms. Kindler claimed that a “subset” of three patents—comparable to the asserted patents—“drove the negotiation.”

    Her evidence?

    1. A list of 15 allegedly infringed patents Super Lighting sent TCP during pre-negotiation correspondence.
    2. “Discussions with Super Lighting personnel” about relative patent importance.

    The Federal Circuit, invoking EcoFactor, explained that this sort of testimony is insufficient. Experts must:

    • show actual evidence that specific asserted patents drove value,
    • reliably apportion portfolio royalties to patented technology at issue, and
    • base methodology on “sufficient facts or data” under Rule 702.

    The panel noted that Ms. Kindler relied heavily on interested-party assertions and bare inference, not documentary evidence or detailed license analysis. Worse, the district court’s Daubert ruling offered no meaningful reasoning, something EcoFactor explicitly condemns.

    Charles Gideon Korrell believes this portion of the opinion will have immediate impact: where portfolio licenses are involved—as they so often are in LED litigation—experts now must produce concrete, comparative evidence or risk exclusion.

    What Happens Next?

    On remand, the district court must conduct a rigorous EcoFactor analysis. If Ms. Kindler’s testimony cannot be rehabilitated with actual evidence, Super Lighting may need a completely new damages theory.

    IV. Takeaways for Patent Litigators

    This case is unusually instructive across multiple doctrinal areas. Several lessons stand out:

    1. Authentication Witnesses Should Not Be a Flashpoint

    Courts must not impose extra-textual disclosure obligations for authentication witnesses. A fact witness who can identify documents disclosed long before trial should generally be permitted.

    2. On-Sale Bar Evidence Requires Corroboration—And Jurors Should See It

    Expert testimony alone cannot carry an on-sale bar unless grounded in record evidence. Excluding documents supporting that testimony is high-risk error.

    3. EcoFactor Now Governs the Damages Landscape

    EcoFactor demands:

    • concrete documentary support,
    • apportionment tied to specific patent value, and
    • a detailed Rule 702 analysis from district courts.

    Blanket adjustments and “trust me, I’ve done this before” methodology are no longer acceptable. Charles Gideon Korrell observes that this trend is pushing damages law toward a more empirical, data-driven model—one many litigants may not be structurally prepared for.

    4. Single Damages Verdicts Are Fragile

    When a verdict hangs on multiple liability findings, any reversible error affecting any theory can unravel the entire award.

    Conclusion

    The Federal Circuit affirmed validity and infringement of the ’140 shock-prevention patent but reversed and remanded on the tube-lamp patents and damages. As Charles Gideon Korrell insightfully puts it, EcoFactor has not just shifted the landscape—it has raised the floor. Going forward, damage experts must bring real evidence, not narrative gloss, especially in portfolio-license cases.

    By Charles Gideon Korrell

  • EcoFactor, Inc. v. Google LLC (En Banc): CAFC Clarifies Daubert Gatekeeping for Patent Damages Experts

    EcoFactor, Inc. v. Google LLC (En Banc): CAFC Clarifies Daubert Gatekeeping for Patent Damages Experts

    In a closely watched en banc decision issued on May 21, 2025, the Federal Circuit reversed the district court’s denial of a new trial on damages in EcoFactor, Inc. v. Google LLC, No. 2023-1101. The court held that the trial court abused its discretion by admitting expert damages testimony that was not based on sufficient facts or data, in violation of Federal Rule of Evidence 702 and Daubert. While the Federal Circuit reinstated the prior panel’s decision on non-damages issues, its en banc ruling significantly clarifies and tightens the standard for admissibility of expert testimony in patent damages cases.

    Background

    EcoFactor sued Google in the Western District of Texas, alleging that Google’s Nest thermostats infringed U.S. Patent No. 8,738,327. The jury found infringement and awarded a $20 million lump-sum damages award based on testimony from EcoFactor’s expert, David Kennedy. Kennedy opined that comparable licenses supported a reasonable royalty of $X per unit and that Google should pay damages on that basis.

    Google challenged the admissibility of Kennedy’s opinion under Daubert, arguing that his damages theory was not based on sufficient facts or reliable methodology. A panel of the Federal Circuit affirmed the district court (with Judge Prost dissenting in part), but the court subsequently granted rehearing en banc to consider whether the trial court complied with Rule 702 and Daubert in admitting Kennedy’s per-unit damages theory.

    The En Banc Holding

    Chief Judge Moore, writing for the majority, reversed the district court and ordered a new trial on damages. The court held that Kennedy’s opinion was inadmissible under Rule 702(b) because it relied on an unsupported factual premise: that three prior licensees (Daikin, Schneider, and Johnson Controls) agreed to a $X per-unit royalty in lump-sum settlements with EcoFactor.

    The court emphasized that Rule 702, especially after its 2023 amendment, requires trial courts to determine whether expert opinions rest on sufficient facts and whether those facts support the conclusions the expert seeks to offer. The court clarified that the judicial gatekeeping function under Daubert is not limited to methodology but extends to whether the factual basis itself is adequately supported by the record.

    Why Kennedy’s Testimony Was Excluded

    Kennedy relied on three license agreements to support his conclusion that a $X per-unit royalty had been accepted by other companies in the market. But the court found:

    • The license agreements expressly stated that the lump sums were not based on unit sales and did not reflect a royalty.
    • The “whereas” clauses recited only EcoFactor’s belief about the $X royalty and did not reflect any agreement or shared understanding with the licensees.
    • Kennedy’s testimony that prior licensees paid $X per unit was not supported by the contracts or any underlying sales data.

    Moreover, EcoFactor’s CEO, Shayan Habib, testified that he lacked access to sales data from the licensees and based his understanding of the lump sums on generalized knowledge of the industry and advice from undisclosed advisors. The court found this insufficient to support Kennedy’s expert conclusions.

    Because Kennedy’s opinion that others paid $X per unit was central to his damages analysis, and because the jury may have relied on that opinion in reaching its verdict, the error was not harmless.

    The Role of the 2023 Amendment to Rule 702

    A key part of the opinion is its reliance on the 2023 amendment to Rule 702, which clarified that courts must determine whether it is “more likely than not” that the proffered expert testimony meets the requirements of the rule. Importantly, the amendment emphasizes that questions of sufficiency of the facts or data are questions of admissibility, not weight. The court explicitly criticized the trend among some trial courts to defer these issues to cross-examination or jury consideration, reaffirming that trial judges must exclude opinions that extend beyond what the expert’s basis and methodology can reliably support.

    Interaction with Appellate Review Standards

    Although not the primary focus of the decision, the ruling has prompted commentary (including from Patently-O) about the Federal Circuit’s application of de novo review to what is ostensibly a discretionary evidentiary ruling. While the court couches its holding as a classic abuse-of-discretion review, its willingness to re-interpret the license agreements and witness testimony may suggest a more searching, fact-driven analysis than the deferential standard traditionally implies.

    Charles Gideon Korrell believes that this raises the question of whether the Federal Circuit is re-calibrating its approach to evidentiary rulings in damages cases, especially where expert conclusions turn on contract interpretation or disputed factual premises.

    Reinforcing Precedent on Licensing and Reasonable Royalties

    The decision is rooted in long-standing precedent regarding the use of license agreements in reasonable royalty calculations:

    EcoFactor builds on this line of cases by reinforcing that a reasonable royalty analysis must be grounded in actual, verifiable facts and that experts cannot rely on implied or asserted beliefs absent factual substantiation.

    Broader Implications: Is the Remedies Remedy Now Complete?

    Charles Gideon Korrell sees that the Federal Circuit’s en banc ruling sends a clear message: damages experts must tie their opinions to the factual record in a way that satisfies Rule 702’s admissibility standard—not just survive cross-examination. This decision may mark the culmination of a doctrinal tightening that began over a decade ago.

    If LaserDynamics began the process and Apple v. Motorola accelerated it, the en banc EcoFactor ruling may indeed represent the near-completion of the “remedies remedy”—a recalibration of how courts scrutinize damages theories in patent litigation.

    Experts must now be prepared not only to explain their methodologies but also to demonstrate a verifiable factual foundation for the inputs to their calculations. When the basis for a per-unit royalty is a prior license, courts will require clear evidence that the license actually reflects such a royalty—not just that a party believes it does.

    Final Thoughts

    While the decision is nominally about one expert’s flawed opinion, Charles Gideon Korrell believes that it carries broader implications for how trial courts are expected to apply Rule 702. The Federal Circuit has reinforced that trial judges must actively police the admissibility of expert testimony, particularly in patent damages cases where technical complexity and legal ambiguity often converge.

    Going forward, Charles Gideon Korrell believes that litigants should expect closer scrutiny of any damages theory that relies on settlement agreements or implied royalty rates—and should be ready to defend the factual integrity of those theories from the outset.

    By Charles Gideon Korrell

  • AMP Plus v. DMF: A Closer Look at Obviousness Analysis

    AMP Plus v. DMF: A Closer Look at Obviousness Analysis

    On March 19, 2025, the United States Court of Appeals for the Federal Circuit issued its decision in AMP Plus, Inc. v. DMF, Inc., affirming the Patent Trial and Appeal Board’s (PTAB) ruling that AMP Plus, doing business as ELCO Lighting, failed to prove claim 22 of U.S. Patent No. 9,964,266 was unpatentable as obvious. This case highlights the rigorous evidentiary requirements for demonstrating obviousness in inter partes review (IPR) proceedings and serves as a cautionary tale for petitioners relying on implicit reasoning rather than explicit proof.

    Obviousness and the Challenge to Claim 22

    ELCO argued that claim 22 of DMF’s patent should be invalidated as obvious in view of two prior art references: Imtra 2011 and Imtra 2007. The key limitation in dispute—referred to as “Limitation M”—requires that the compact recessed lighting system be “coupled to electricity from an electrical system of a building.”

    PTAB found that ELCO failed to present sufficient evidence demonstrating that a person of ordinary skill in the art (POSITA) would have modified the marine lighting systems disclosed in Imtra 2011 to be installed in a building. The Federal Circuit affirmed this conclusion, emphasizing that an obviousness argument must be supported by more than assumptions or conclusory statements.

    The Federal Circuit’s Analysis of ELCO’s Argument

    ELCO’s IPR petition asserted that “wire connections between the fixture and the power source can be made in a variety of ways” and that the use of junction boxes in lighting systems was well known. However, PTAB determined—and the Federal Circuit agreed—that ELCO never specifically addressed how the prior art actually disclosed or suggested adapting the marine lighting system for a building’s electrical infrastructure.

    The court underscored several key deficiencies in ELCO’s argument:

    1. Lack of Direct Evidence – The cited portions of the Imtra 2011 brochure and supporting expert testimony never explicitly discussed installation in a building’s electrical system. Instead, the reference described marine applications, leaving a gap in ELCO’s argument about how or why a POSITA would have been motivated to adapt it for use in buildings.
    2. Failure to Establish Motivation to Combine – While ELCO asserted that modifying a marine lighting system for a building would have been an obvious design choice, PTAB found—and the Federal Circuit agreed—that ELCO did not provide sufficient evidence of a motivation to make that change. As the Supreme Court held in KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398 (2007), an obviousness analysis must consider whether a POSITA would have been motivated to make the modification, not just whether they could have.
    3. Improper Reliance on Expert Testimony – ELCO relied on its expert’s declaration to argue that a POSITA would recognize the adaptability of marine lighting systems to buildings. However, the Federal Circuit found that the cited paragraphs of the expert report did not actually support this assertion, as they failed to address the specific limitation at issue—installation in a building’s electrical system.
    4. The Importance of Addressing Every Claim Limitation – The court reaffirmed the principle that every limitation in a claim must be shown to be disclosed or suggested by the prior art. Because ELCO failed to adequately address Limitation M, its obviousness argument fell short, regardless of the strength of its other arguments.

    Lessons for Patent Practitioners and Petitioners

    This decision reinforces a fundamental rule in patent litigation and IPR proceedings: Obviousness cannot be assumed; it must be demonstrated with clear, persuasive evidence. Key takeaways include:

    • IPR petitions must explicitly address each claim limitation. Courts and PTAB will not fill in evidentiary gaps left by a petitioner’s argument.
    • Obviousness requires more than a general assertion of industry knowledge. Petitioners must show both how the prior art discloses a limitation and why a POSITA would have been motivated to modify it in the claimed manner.
    • Expert testimony must be specific and directly tied to claim limitations. Vague or conclusory statements from experts will not suffice to establish obviousness.

    Conclusion

    The Federal Circuit’s ruling in AMP Plus v. DMF underscores the challenges in proving obviousness in IPR proceedings. While ELCO had strong prior art references, its failure to explicitly demonstrate how a POSITA would have modified marine lighting for building use proved fatal to its case. For future patent challengers, this case serves as a reminder that thorough, well-supported arguments are critical in overcoming the presumption of patent validity.

    By Charles Gideon Korrell

  • Patent Litigation and Expert Testimony: Lessons from Trudell v. D R Burton

    The recent decision in Trudell Medical International Inc. v. D R Burton Healthcare, LLC by the United States Court of Appeals for the Federal Circuit highlights significant issues in intellectual property law, particularly in the realm of patent litigation. This case, which revolves around the infringement of U.S. Patent No. 9,808,588, serves as a critical reminder of the procedural and evidentiary requirements in patent disputes.

    Background of the Case

    Trudell Medical International Inc. (“Trudell”) sued D R Burton Healthcare, LLC (“D R Burton”) for infringement of its patent covering oscillatory positive expiratory pressure (OPEP) therapy devices. Trudell alleged that D R Burton’s vPEP®, iPEP®, PocketPEP®, and related products infringed claims 1–7, 9, and 18 of its patent. After a three-day trial, the jury found the asserted claims valid but not infringed.

    Trudell appealed on multiple grounds, including the improper admission of expert testimony by Dr. John Collins, an expert retained by D R Burton. The Federal Circuit ultimately reversed the district court’s decision allowing Dr. Collins’ testimony, granted a new trial on infringement, and ordered the case to be reassigned to a different judge.

    Key Legal Issues in the Case

    1. Expert Testimony and Compliance with Federal Rules

    One of the most significant issues in the case was the admission of expert testimony. Under Federal Rule of Civil Procedure 26(a)(2), expert reports must include a complete statement of opinions, the basis and reasons for those opinions, supporting data, and a list of prior cases where the expert has testified. Additionally, under Rule 37(c)(1), failure to disclose expert information as required by Rule 26 results in automatic exclusion unless the failure is substantially justified or harmless.

    The court found that D R Burton failed to comply with these disclosure requirements, as Dr. Collins did not submit a timely expert report on noninfringement. His testimony was introduced at trial despite not being disclosed during discovery, depriving Trudell of an opportunity to challenge or cross-examine his findings adequately. The court held that this failure was neither substantially justified nor harmless, leading to the exclusion of his testimony and the ordering of a new trial.

    2. Claim Construction and Expert Reliability

    The Federal Circuit also addressed issues with the methodology of Dr. Collins’ testimony. The district court had construed specific claim terms, including the definition of “a vane” and “rotate relative to the opening.” Despite this, Dr. Collins provided testimony that contradicted the court’s construction, effectively redefining key claim terms. His approach was deemed unreliable under Federal Rule of Evidence 702, which requires that expert opinions be based on reliable principles and methodologies.

    This aspect of the decision underscores the importance of ensuring that expert witnesses adhere to judicial claim constructions rather than reinterpreting patent terms in a manner inconsistent with the court’s ruling.

    3. The Impact of Procedural Missteps on Patent Trials

    Another crucial takeaway from this case is the procedural mismanagement at the district court level. The judge overseeing the case made multiple contradictory rulings regarding Dr. Collins’ testimony, initially excluding it, then allowing it, then reversing again. Additionally, comments made by the judge suggested a predisposition toward resolving the case quickly, rather than ensuring a fair trial. These concerns led the Federal Circuit to order a reassignment of the case to a different judge on remand—a rare but important corrective measure to preserve judicial impartiality.

    Implications for Patent Law and Litigation Strategy

    This decision has several important takeaways for patent litigants:

    • Strict Compliance with Expert Disclosure Rules: Failure to provide timely and complete expert reports can lead to exclusion of testimony, which can be case-dispositive in patent disputes.
    • Adherence to Claim Construction: Experts must base their testimony on the court’s claim construction and avoid introducing conflicting interpretations.
    • The Role of Judicial Conduct in Patent Trials: The reassignment of this case underscores the importance of judicial impartiality and procedural fairness in complex intellectual property disputes.

    Conclusion

    The Trudell v. D R Burton case highlights the complexities of patent litigation, particularly in the areas of expert testimony and claim construction. For attorneys and companies engaged in intellectual property disputes, this ruling reinforces the necessity of procedural diligence, expert reliability, and fair trial practices. As the case moves forward on remand, it will be interesting to see how the new trial unfolds without the tainted expert testimony that influenced the first jury’s verdict.

    By Charles Gideon Korrell

  • BEARBOX LLC v. LANCIUM LLC: A Legal Examination of Inventorship and State Law Preemption in Patent Law

    In the recent case of BearBox LLC v. Lancium LLC, the United States Court of Appeals for the Federal Circuit addressed pivotal issues concerning inventorship claims and the preemption of state law by federal patent statutes. This case underscores the intricate balance between state and federal jurisdictions in intellectual property disputes.

    Case Background

    Austin Storms, founder of BearBox LLC, engaged in discussions with Lancium LLC’s co-founders, Michael T. McNamara and Dr. Raymond E. Cline, Jr., during a Bitcoin mining conference. Subsequently, Storms sent an email containing technical information about BearBox’s technology. Lancium later secured U.S. Patent No. 10,608,433 (“the ‘433 patent”), leading Storms to assert that he should be recognized as an inventor. BearBox pursued legal action, alleging conversion under Louisiana state law and seeking correction of inventorship on the ‘433 patent.

    Key Legal Issues Addressed

    1. Preemption of State Law Conversion Claim
      • BearBox’s conversion claim centered on Lancium’s alleged unauthorized use of its unpatented technology. The district court dismissed this claim, determining it was preempted by federal patent law. The court reasoned that allowing such a state law claim would conflict with the objectives of federal patent statutes, which aim to promote public disclosure and free use of unpatented ideas. The Federal Circuit affirmed this decision, emphasizing that state laws cannot offer patent-like protection to intellectual creations unprotected under federal law.
    2. Exclusion of Supplemental Expert Report
      • BearBox submitted a supplemental expert report after the close of discovery without seeking the court’s permission. The district court excluded this report, citing procedural rules and the untimely nature of its submission. The Federal Circuit upheld this exclusion, noting that BearBox had ample opportunity to address claim construction issues earlier in the proceedings and failed to justify the delayed submission.
    3. Inventorship Claims
      • At the heart of the dispute was whether Storms should be recognized as a sole or joint inventor of the ‘433 patent. The district court, after a thorough bench trial, found that BearBox did not provide clear and convincing evidence to support Storms’ inventorship claims. The court highlighted that the information shared by Storms did not establish his conception of the claimed invention, nor did it precede Lancium’s independent development. The Federal Circuit affirmed this finding, underscoring the necessity for corroborated evidence in inventorship disputes.

    Implications for Intellectual Property Law

    This case reinforces the principle that federal patent law preempts state laws that attempt to grant patent-like protections to unpatented ideas. It also highlights the critical importance of timely and procedurally correct submissions in litigation, especially concerning expert reports. For inventors and companies, the decision underscores the necessity of maintaining thorough documentation and clear communication when collaborating or sharing technical information, as these records are vital in establishing claims of inventorship.

    In conclusion, the BearBox LLC v. Lancium LLC decision provides valuable insights into the complexities of patent law, particularly regarding the boundaries of state and federal jurisdictions and the stringent requirements for proving inventorship.

    By Charles Gideon Korrell