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  • The Preemption Doctrine: A Necessary Course Correction After Recentive v. Fox

        By Manav Das —

    Federal Circuit SealThe landscape of patent law for artificial intelligence (AI) and machine learning (ML) innovations has become fraught with uncertainty.  The U.S. Court of Appeals for the Federal Circuit's precedential opinion in Recentive Analytics, Inc. v. Fox Corp.[1], issued on April 18, 2025, represents a watershed moment for the starkness with which it exposes the fundamental inadequacies of the current subject matter eligibility approach under 35 U.S.C. § 101.  In its first opinion addressing the patent eligibility of ML technologies, the Court affirmed the invalidation of four patents, establishing a formidable and flawed precedent that threatens to stifle innovation in one of the most critical technological sectors of our time.  The decision, while consistent with a problematic line of jurisprudence stemming from Alice Corp. v. CLS Bank International[2], serves as a quintessential example of how the two-step Alice/Mayo framework is ill-equipped to evaluate the true inventive character of ML inventions.  By mischaracterizing applied ML as "generic" and dismissing the very process of training as non-inventive, the Court has constructed a legal framework that is profoundly disconnected from technological reality, creating a potentially insurmountable barrier for patenting a vast and vital category of AI innovations.  A meticulous deconstruction of the Recentive decision reveals not just a flawed outcome, but a flawed legal test as well that is in urgent need of reform.

    I.    The Factual and Procedural Background of Recentive

    The case centered on four patents held by Recentive Analytics, which fell into two families:  the "Machine Learning Training" patents (U.S. Patent Nos. 11,386,367 and 11,537,960) and the "Network Map" patents (U.S. Patent Nos. 10,911,811 and 10,958,957).  The patents claimed methods and systems for using ML to optimize the scheduling of live television events and to generate dynamic network maps for broadcasters; tasks that, as the Court noted, were previously performed manually by humans.  Recentive sued Fox Corp. and its affiliates for infringement, and Fox responded with a motion to dismiss, arguing that the patents were directed to ineligible subject matter under § 101.

    The case highlights by their absence some drafting "best practices" that were not followed and that eventually weighed against the patentee.  For example, the drafters included language stating that the invention could use "any suitable machine learning technique,"[3] providing a laundry list of conventional models such as neural networks, decision trees, support vector machines, and regressions.  This broad, non-specific language provided the Court with textual basis to characterize the claimed technology as "generic" and "conventional."

    Additionally, during litigation, the patentee admitted that it was "not claiming machine learning itself" and that the patents did not claim a specific method for "improving the mathematical algorithm or making machine learning better."  Recentive also acknowledged that "the concept of preparing network maps[] [had] existed for a long time," and that prior to computers, "networks were preparing these network maps with human beings."[4]  These admissions effectively allowed the Court to conclude that the patents did nothing more than apply existing, off-the-shelf technology to a new field.  Unfortunately, the perceived weaknesses related to the Recentive case have led to the creation of a broad, damaging precedent for the entire AI industry, a precedent that future innovators must now navigate.

    A.    The Alice Step One Analysis: An Overly Broad Characterization of the "Abstract Idea"

    Applying the first step of the Alice/Mayo framework, the Federal Circuit had to determine whether the claims were "directed to" a patent-ineligible concept, such as an abstract idea.  The Court affirmed the District Court's finding that they were, characterizing the patents as being directed to the abstract ideas of "producing event schedules and network maps using known generic mathematical techniques".

    The core of the Court's reasoning culminated in an overbroad holding:  "patents that do no more than claim the application of generic machine learning to new data environments, without disclosing improvements to the machine learning models to be applied, are patent ineligible under § 101."[5]  This holding effectively invalidates a common and crucial form of innovation in the AI field:  the novel application of existing ML tools to solve problems in new domains.

    The Court explicitly rejected Recentive's argument that applying ML to a new field of use — in this case, television broadcasting and event scheduling — could confer patent eligibility.  Citing established precedent, the Court reiterated that "[a]n abstract idea does not become nonabstract by limiting the invention to a particular field of use or technological environment."[6]  Similarly, the Court was unpersuaded by the argument that the invention was patentable because it applied existing technology to a novel database or data environment.[7]  This line of reasoning is particularly problematic for AI, where the curation and application of novel datasets is often a key part of the inventive process.

    Furthermore, the Court dismissed Recentive's claims that its inventions were patent-eligible by the fact that "(using existing machine learning technology) they perform a task previously undertaken by humans with greater speed and efficiency than could previously be achieved."[8]  The Federal Circuit has consistently held that improvements in speed or efficiency resulting from the use of a generic computer do not, by themselves, create eligibility unless they are based on improved computer techniques.

    By equating a sophisticated, trained ML model with a "generic computer," the Court overlooked the transformative technological leap that such automation represents.  This line of reasoning has been problematic even prior to Recentive.  Improvements in speed or efficiency resulting from the use of a generic computer or limiting an abstract idea to a particular technological environment are issues that are best handled using the evidentiary approach under Sections 102 and 103.  Indeed, some of these issues should be analyzed from a viewpoint of a person of ordinary skill at the time of the invention.  However, by bringing such issues under the ambit of Section 101, courts have created a legal framework that is confusing, arbitrary, unreliable, and utterly subjective.  This overly broad characterization at Alice Step One set the stage for the claims' inevitable failure at Step Two.

    B.    The Alice Step Two Analysis: The Search for a Non-Existent "Inventive Concept"

    Having concluded that the claims were directed to an abstract idea, the Court proceeded to the second step of the Alice test, which asks whether the claims include an "inventive concept" sufficient to "transform" the abstract idea into a patent-eligible application. The Court searched for something "significantly more" than the abstract idea itself but concluded that it could "perceive nothing in the claims" that met this standard.[9]

    Recentive argued that the inventive concept was the use of "machine learning to dynamically generate optimized maps and schedules based on real-time data and update them based on changing conditions."[10]  The Court dismissed this argument, stating that this was "no more than claiming the abstract idea [of generating event schedules and network maps] itself"[11] and failed to identify any transformative element.

    The Court's most consequential finding at Step Two was its characterization of core ML processes as non-inventive.  It stated that "requirements that the machine learning model be 'iteratively trained' or dynamically adjusted in the Machine Learning Training patents do not represent a technological improvement."[12]  This was despite Recentive's argument that its application of machine learning is not generic because "Recentive worked out how to make the algorithms function dynamically, so the maps and schedules are automatically customizable and updated with real-time data,"[13] . . . and because "Recentive's methods unearth 'useful patterns' that had previously been buried in the data, unrecognizable to humans."[14]  This alone should have been sufficient for a finding of subject matter eligibility.

    The Court's analysis reveals a profound judicial misunderstanding of where innovation in applied ML frequently resides.  The specific process of iterative training on a dataset to solve a particular problem is often the very heart of the invention.  By deeming this process inherent and routine, the Court effectively precludes from patent protection a major avenue of AI innovation.  Moreover, when a "generic" ML model is trained to perform a specific task on a specific training dataset, this clearly transforms the "generic" ML model into a special purpose ML model, which should be subject matter eligible.  Whether such a special purpose ML model and/or use thereof is patent-eligible is properly a consideration under Sections 102, 103, and 112.

    Throughout its analysis, the Court repeatedly returned to the theme of the "missing 'how.'"  It faulted the patents because "neither the claims nor the specifications describe how such an improvement was accomplished"[15] and failed to "delineate steps through which the machine learning technology achieves an improvement."[16]  This demand for a detailed, step-by-step recitation of "how" a technological improvement is achieved is fundamentally misaligned with the nature of ML.  In many cases, the improvement is an emergent property of the training process; the model learns to recognize patterns that may be too complex for a human to explicitly define or describe or even know.  To demand a precise explanation of "how" a neural network achieves its optimized state is to demand an explanation of the unexplainable, setting a standard that is not just high, but often technologically impossible.  This judicial skepticism toward emergent properties and learning-based systems indicates that the Alice/Mayo framework is not merely being applied erroneously; it is being applied in a way that is structurally biased against the very nature of modern AI innovation.

    II.    The "Generic" Model Fallacy: A Fundamental Disconnect Between Patent Law and ML Reality

    The Recentive decision rests upon a flawed premise:  that the patents claimed the mere application of a "generic" machine learning model.  This characterization, while convenient for the Court's legal analysis, is a legal fiction that willfully ignores the technical realities of how machine learning models are developed, trained, and deployed.  It creates a false dichotomy that serves to invalidate legitimate technological advancements and reveals a deep, structural disconnect between § 101 jurisprudence and the actual practice of AI innovation.  Challenging this "generic model" fallacy is essential to understanding why the current patent eligibility test is failing.

    A.    General-Purpose vs. Special-Purpose AI: A Critical Distinction

    To understand the Court's error, one must first grasp the critical technical distinction between general-purpose and special-purpose AI models.  Foundation models, also referred to as general-purpose AI (GPAI), are large models like OpenAI's ChatGPT[17], Meta's LLaMA[18], Google's Gemini[19], image generation models such as OpenAI's DALL-E[20], and so forth which are pre-trained on vast, diverse datasets, and often using unsupervised or self-supervised learning.  These models are the "general" tools of the AI world. They are not typically designed for any single task but possess a broad range of capabilities, such as text summarization, language translation, and image generation.  They are, in essence, powerful but unspecialized starting points.  Typically, prompts are used to discover the emergent utilities of such models.  Such models are also extremely expensive and cannot be developed without vast investments of time, money, and specialized personnel.[21]

    In contrast, specialized models, also referred to as narrow AI, are AI systems that have been designed, trained, or fine-tuned to perform a specific task or operate within a specific domain with high efficiency and accuracy.  A model designed to improve diagnosis and drug discovery in healthcare, enhance risk management and fraud detection in finance, perform predictive maintenance and production optimization in manufacturing, or, as in Recentive's case, optimize television schedules, is a specialized model.  These models often possess more streamlined architectures and are more cost-effective for their narrow purpose, but they require extensive, carefully curated, domain-specific training data to achieve their specialized function.  A primary and ubiquitous method for creating a specialized model is to take a general-purpose architecture (or even a pre-trained foundation model) and train or fine-tune it on a specific dataset to solve a specific problem.

    B.    The Act of Training as an Act of Invention: Transforming a General Tool into a Specific Machine

    The central error in the Recentive court's analysis was its failure to recognize this distinction.  The Court focused on the starting point of the invention — a generic class of algorithms like "neural networks" or "decision trees" listed in the specification — rather than the end product of the invention:  a fully trained, specialized model capable of performing a specific, useful function it could not perform before training.

    The act of training a ML model itself is an act of invention that should be subject matter eligible.  The patentability of this act of invention is a separate consideration.  The process of collecting and curating a specific dataset (e.g., historical broadcast schedules, event parameters, target features, venue locations, and ticket sales, as described in the Recentive patents) and then applying computational resources to train a model on that data is what transforms the general algorithmic tool into a special-purpose machine.

    Once trained, the model is no longer "generic."  It is a new technological artifact.  Its internal configuration, such as the millions or billions of weights and biases within its neural network, has been fundamentally altered and optimized to embody the patterns and relationships learned from the training data.  This newly configured model is a specific machine, designed and built for a particular purpose.  The Court's dismissal of this transformation as a mere "application" of an abstract idea is akin to saying that programming a general-purpose computer to perform a new and useful task is not a technological improvement because the underlying computer hardware is "generic."

    This reveals a fundamental contradiction at the heart of the court's reasoning.  On one hand, the Court dismisses the process of "iterative training" as an inherent, non-inventive aspect of machine learning.  On the other hand, it demands that the patentee show a specific improvement to the machine learning model itself.  For the vast majority of applied AI inventions, the specific improvement is the direct result of that very training process.  The trained model is the improved model.  By treating the process as inherent and the resulting application as abstract, the Court creates an inescapable trap that leaves no conceptual space for patentability.  This approach, which dissects the invention into its constituent parts ("known training technique" and "abstract application domain") and finds no eligible subject matter in the pieces, fails to recognize the inventive character of the integrated whole.  This is a well-recognized flaw in § 101 analysis, but one that is particularly damaging in the context of AI.

    C.    The Legal Consequences of the "Generic" Fallacy

    By enshrining the "generic model" fallacy into precedential law, the Recentive decision has profound and damaging consequences.  It effectively declares that one of the most common and powerful forms of innovation in the modern technology industry — the practical application and specialization of ML models to solve real-world problems — is presumptively patent-ineligible.

    This essentially creates a paradox:  the more fundamental and broadly applicable a foundational ML technique (like a neural network architecture) becomes, the less likely its specific, value-creating applications are to be deemed patentable.  This is contrary to the constitutional purpose of the patent system, which is to incentivize the reduction of abstract principles to practice. The decision signals that the current § 101 framework is inherently biased toward inventions that can be easily described as a novel physical mechanism or a discrete, new mathematical algorithm.  This framework is structurally incapable of properly valuing inventions where the innovation is embodied in the complex configuration of a system (like the weights of a neural network) that is achieved through a process of data-driven learning.

    The inevitable result of this legal uncertainty and subjectivity is that innovators will be pushed away from the patent system and toward trade secret protection.  While trade secrecy can protect certain AI innovations, such as model weights or proprietary training data, it does so at a great cost to society.  The patent system's core bargain is one of disclosure in exchange for a limited monopoly.  By making patents for applied AI exceedingly difficult to obtain and enforce, the law discourages this disclosure, slowing the overall pace of innovation and preventing the public dissemination of knowledge that is crucial for building the next generation of technology.  At the same time, foreign nations may allow such innovations to be patentable, thereby creating a competitive barrier to American commerce and economic leadership.

    III.    Restoring the Cornerstone of § 101: Preemption as a Superior Analytical Framework

    The labyrinthine complexity of the Alice/Mayo framework, with its ambiguous steps and technologically unsound assumptions, is not an accidental feature; it is a symptom of a deeper doctrinal malady.  The test has become unmoored from its conceptual anchor.  The current two-step inquiry should be set aside in favor of a direct analysis of preemption.  This approach, which is more faithful to the Supreme Court's own foundational jurisprudence, offers a clearer, more consistent, and technologically neutral standard for judging the patent eligibility of machine learning and other computer-implemented inventions.  It is the necessary course correction to rescue § 101 from its current state of incoherence.

    A.    The Doctrinal Foundation: Preemption as the "Ultimate Touchstone" of § 101

    A historical review of the judicial exceptions to patent eligibility — laws of nature, natural phenomena, and abstract ideas — reveals a single, unifying concern:  preemption.  As noted in Alice, the Supreme Court has "repeatedly emphasized this . . . concern that patent law not inhibit further discovery by improperly tying up the future use of these building blocks of human ingenuity."[22]  The fear is that granting a patent on a basic tool of science or technology, such as a mathematical formula or a fundamental economic practice, would "tend to impede innovation more than it would tend to promote it."[23]

    This concern animates the Court's landmark § 101 decisions.  In Gottschalk v. Benson[24], the Court invalidated a claim for converting numerical information because it would "wholly pre-empt the mathematical formula" and effectively be a patent on the algorithm itself.  Conversely, in Diamond v. Diehr[25], the Court found claims using the Arrhenius equation to be eligible because they were tied to a specific industrial process for curing rubber and did not preempt all uses of the equation.  More recently, in Bilski v. Kappos[26], the Court cautioned against claims that would "pre-empt the use of [an] approach in all fields," and in Alice itself, the Court unequivocally stated that "the concern that drives this exclusionary principle is one of pre-emption".  Preemption is not merely a peripheral consideration; it is the "ultimate touchstone" and the very reason the judicial exceptions exist.

    B.    The Jurisprudential Drift: How the Federal Circuit Unmoored the Test from Preemption

    Despite the Supreme Court's clear guidance, the Federal Circuit's application of the two-step Alice/Mayo framework has evolved into a rigid, formalistic exercise that frequently sidelines, and at times openly dismisses, the core preemption inquiry.  The test has become an end in itself, rather than a means to address the underlying policy concern.

    This jurisprudential drift is most evident in the Federal Circuit's explicit holdings on the matter.  In cases like Ariosa Diagnostics, Inc. v. Sequenom, Inc.[27], the Court has declared that "the absence of complete preemption does not demonstrate patent eligibility."[28]  This statement represents a stunning departure from the doctrine's foundational logic.  If the sole purpose of the judicial exception is to prevent the harm of preemption, then the demonstrated absence of that harm should be dispositive of eligibility.  To hold otherwise is to allow the exception to "swallow all of patent law."[29]

    The "abstract idea" category, in particular, has been expanded far beyond its intended role as a proxy for preemptive claims.  It has become a mechanism for courts to invalidate claims that are specific, applied, and non-preemptive simply because their subject matter can be generalized to a high level of abstraction, such as a "fundamental economic practice" or a "mental process."  This has led to the erratic and unpredictable results that now plague § 101 jurisprudence, creating an environment of profound uncertainty for innovators, investors, and the patent system as a whole.

    The internal logic of the two-step framework is itself flawed.  The test allows, and even encourages, a court at Step One to label a claim as being "directed to" an abstract idea even if the claim is narrow and poses no realistic threat of preemption.  This initial characterization, however, is not neutral; it taints the entire subsequent analysis.  At Step Two, the Court is then asked to search for an "inventive concept," but the elements of the claim that were used to label it "abstract" in the first place are effectively discounted.  This makes it nearly impossible for a claim, once branded "abstract," to be saved.  The result is that specific, practical, and non-preemptive inventions are routinely invalidated.  The Supreme Court created the "abstract idea" category as a tool to identify potentially preemptive claims; the Federal Circuit has transformed the tool into the test itself.  By focusing on whether a claim can be described as abstract, rather than whether it is preemptive in its scope, the Court has inverted the analysis and created a doctrine that is inconsistent and untethered from its policy moorings.

    C.    A Better Way Forward: Applying a Preemption-First Analysis

    One remedy for this doctrinal confusion is to return to first principles.  The vague, two-step Alice/Mayo inquiry should be replaced with a more direct and coherent test focused on the only question that matters:  does the claim, as a whole, preempt all practical applications of a law of nature, natural phenomenon, or abstract idea?  If the answer is no, the claim should be deemed patent-eligible under § 101, and the examination should proceed to the substantive requirements of novelty (§ 102), non-obviousness (§ 103), and enablement (§ 112), which are the proper statutory vehicles for assessing the inventive merit of a specific technological implementation.

    Applying this preemption-first analysis to the facts of Recentive demonstrates its superiority.  The claims at issue were directed to a specific application:  using ML to generate optimized television schedules and network maps based on specific types of data, such as historical broadcast information and real-time parameters.

    • Did these claims preempt the abstract idea of scheduling?  No.  Humans and other computer systems remained free to create schedules.
    • Did they preempt all uses of machine learning?  Clearly not.
    • Did they even preempt all uses of machine learning for scheduling?  No.  A competing innovator would remain free to develop a different scheduling system using a different ML model, a different set of training data, different pre- or post-processing techniques, or different feature engineering to achieve a similar result.  The claims did not "wholly pre-empt" a fundamental building block.

    Because the claims under consideration in Recentive posed no danger of disproportionately tying up a basic tool of science or commerce, they should have been found eligible under a proper, preemption-focused § 101 analysis.  Whether Recentive's specific implementation was novel over the prior art or non-obvious to a person of ordinary skill in the art are separate, important questions — but they are questions for §§ 102 and 103, not § 101.  A preemption-centric framework would restore § 101 to its intended role as a "coarse filter" designed to screen out only those claims that truly seek to monopolize a fundamental principle, not those that claim a specific, practical application of one.

    IV.    Conclusion: Realigning Patent Law with Technological Reality

    The Federal Circuit's decision in Recentive is not an anomaly but a predictable outcome of a broken legal framework where a flawed reasoning has been reinforced and amplified.  The ruling, which effectively deems the common practice of applying known machine learning techniques to new domains as patent-ineligible, is built upon the "generic model" fallacy — a fundamental misapprehension of how innovation in artificial intelligence occurs.  By dismissing the transformative act of training as "inherent" and demanding a specific, articulable improvement to the underlying algorithm, the Court has created a standard that is profoundly misaligned with the emergent, data-driven nature of modern technology.

    The ultimate solution lies not in more intricate drafting strategies but in doctrinal reform.  The Alice/Mayo two-step test, having become unmoored from its conceptual foundation, has proven to be an unreliable and technologically unsound instrument.  Its vague standards and internal contradictions have injected a level of uncertainty into patent law that chills investment and discourages the public disclosure that the patent system is meant to foster.

    A clear, direct, and principled analysis based on preemption is the viable path forward.  Restoring preemption as the cornerstone of the § 101 inquiry would provide the clarity, predictability, and technological neutrality that the patent system desperately needs.  It would properly relegate § 101 to its intended role as a coarse filter, shifting the substantive examination of an invention's merit back to the well-established doctrines of novelty, non-obviousness, and enablement.  Such a reform, whether enacted by the judiciary or through legislative action, is essential to realign U.S. patent law with the realities of modern innovation and to ensure that the law continues to fulfill its constitutional mandate to "promote the Progress of Science and useful Arts."

    [1] Recentive Analytics, Inc. v. Fox Corp., No. 23-2437 (Fed. Cir. 2025)

    [2] Alice Corp. Pty. Ltd. v. CLS Bank Int'l, 573 U.S. 208 (2014)

    [3] Recentive Analytics, Inc. v. Fox Corp. at 5

    [4] Id. at 7

    [5] Id. at 18

    [6] Id. at 14 (citing Intell. Ventures I LLC v. Capital One Bank (USA), 792 F.3d 1363, 1366 (Fed. Cir. 2015))

    [7] Id. at 14-15

    [8] Id. at 15

    [9] See, generally, id. at 16

    [10] Id.

    [11] Id. at 17

    [12] Id. at 12

    [13] Appellant's Reply Br. 2,

    [14] Id.

    [15] Id. at 12-13

    [16] Id. at 13

    [17] https://openai.com/chatgpt/overview/

    [18] https://www.llama.com/

    [19] https://ai.google.dev/gemini-api/docs/models

    [20] https://openai.com/index/dall-e/

    [21] https://www.tensorops.ai/post/understanding-the-cost-of-large-language-models-llms

    [22] Alice Corp. v. CLS Bank Int'l, 573 U.S. 208, 214 (2014)

    [23] See, e.g., Mayo Collaborative Services v. Prometheus Labs., Inc., 566 U.S. 66, 71 (2012)

    [24] Gottschalk v. Benson, 409 U.S. 63 (1972)

    [25] Diamond v. Diehr, 450 U.S. 175 (1981)

    [26] Bilski v. Kappos, 561 U.S. 593 (2010)

    [27] Ariosa Diagnostics, Inc. v. Sequenom, Inc., 788 F.3d 1371 (Fed. Cir. 2015)

    [28] Id. at 1379

    [29] Alice Corp. v. CLS Bank Int'l, 573 U.S. 208, 217 (2014)

  • Eye Therapies LLC v. Slayback Pharma, LLC (Fed. Cir. 2025)

    By Kevin E. Noonan —

    Federal Circuit SealPatent law in many respects has its own language and idiosyncratic expressions, and one such respect involves so-called "transitional" words or phrases (discussed in greater depth in the Manual of Patent Examination Procedure § 2111.03).  They are termed "transitional" because they mediate the transition between a claim preamble and the elements of the invention recited therein.  The most common such word is "comprises" or "comprising," which indicates that the claim drafter intends the element to encompass what is expressly recited and anything else (within the limits of what the skilled artisan would understand would be operable; this is not an "everything but the kitchen sink" situation).  On the other hand, the words "consisting of" indicate the exact opposite:  the elements recited following this phrase are limited to just what is recited and nothing more.  In what was considered in simpler days to be especially arcane arts such as chemistry there arose a somewhat looser version of this more restricted terminology, the phrase "consisting essentially of."  This transitional phrase was much more limited than "comprising" but permitted a slightly broader scope than "consisting of"; examples included additional unrecited elements in complicated chemical combinations like shampoos.  Any "loosening" of the strictures of "consisting of" is limited to such elements that do not materially affect the "basic and novel" characteristics of the claimed invention.  See, as examples, In re Herz, 537 F.2d 549, 551-52 (CCPA 1976), and Atlas Powder v. E.I. duPont de Nemours & Co., 750 F.2d 1569 (Fed. Cir. 1984).

    The proper construction of this phrase was at issue in Eye Therapies LLC v. Slayback Pharma, LLC, which arose as an inter partes review of all claims of Patent Owner Eye Therapies' U.S. Patent No. 8,293,742.  This patent claims a method to reduce eye redness using a low-concentration dose of brimonidine, which active ingredient is described in a footnote as being "an alpha-adrenergic receptor agonist, a category of compounds known to cause vasoconstriction."  The footnote goes on to explain that this vasoconstrictive effect counteracts vasodilation, which is the cause of many "clinically undesirable events" such as "surface hemorrhage and hyperemia following Lasik surgery" and "eye redness (conjunctival hyperemia)."

    Claims 1 and 3 are set forth in the opinion as representative:

    1.  A method for reducing eye redness consisting essentially of administering brimonidine to a patient having an ocular condition, wherein brimonidine is present at a concentration between about 0.001% weight by volume and about 0.05% weight by volume.

    3.  A method for reducing eye redness consisting essentially of topically administering to a patient having an ocular condition a composition consisting essentially of brimonidine into ocular tissue, wherein pH of said composition is between about 5.5 and about 6.5, wherein said brimonidine concentration is between about 0.001% and about 0.025% weight by volume and wherein said composition is formulated as an ocular drop.

    (wherein the italicized transitional language was at issue in this appeal).  The opinion sets forth the ex parte prosecution context of the importance of this transitional phrase, wherein the patentee had amended the word "comprising" to "consisting essentially of" in the face of a novelty rejection asserted using prior art disclosing a combination of brimonidine and brinzolamide, and applicant argument that "the revised claims 'do not require the use of any other active ingredients (emphasis added) in addition to brimonidine'" (and wherein the examiner expressly recited this argument in their Notice of Allowance).

    In its Petition, Slayback challenged claims 1-6 of the '742 patent; in the Final Written Decision (FWD), the Patent Trial and Appeal Board found all claims of the patent to be invalid for obviousness.  In its claim construction, the Board expressly rejected Patent Owner's arguments that "consisting essentially of" limited the claim to exclude any other active ingredients (despite both the patent applicant and examiner expressly having relied on this distinction in prosecution of the '742 patent claims to allowance).  The Board's reasoning in the FWD was that to do so would construe the phrase to have the same scope as "consisting of."  Under the Board's construction, "the claimed methods cannot include additional active ingredients that are 'required' to perform the method" (emphasis in FWD).  Nevertheless, the Board considered the addition of other active ingredients that "would not materially affect the basic and novel characteristics of the invention" could be included within the scope of the claim.  Under this construction, the prior art disclosure of the combination of combination of brimonidine and brinzolamide would render the '742 claims obvious.  This appeal followed.

    The Federal Circuit reversed in part and vacated in part the PTAB's decision and remanded, in an opinion by Honorable Mark C. Scarsi, District Judge from U.S. District Court for the Central District of California, sitting by designation, joined by Judges Taranto and Stoll.  The panel opinion came straight to the point:  in view of the prosecution history the Board erred in construing the phrase "consisting essentially of" to encompass methods using active ingredients other than brimonidine.  Because this error permitted the Board to consider the combination prior art formulations as falling within the scope of the claim and thus being obvious, the Court vacated the Board's obviousness determination and remanded.

    The basis for the panel's decision that the Board erred in construing "consisting essentially of" was that this phrase had been "long understood" to "permit inclusion of components not listed in the claim, provided that they do not 'materially affect the basic and novel properties of the invention,'" citing AK Steel Corp. v. Sollac, 344 F.3d 1234, 1239 (Fed. Cir. 2003).  And under Phillips v. AWH Corp., 415 F.3d 1303, 1312–13 (Fed. Cir. 2005) (en banc), a patent applicant "can alter the typical meaning . . . by mak[ing] the intended meaning clear in the specification or disclaim an alternative meaning in the prosecution history," citing Ecolab, Inc. v. FMC Corp., 569 F.3d 1335 (Fed. Cir. 2009).  The panel agreed with Eye Therapies' argument that the prosecution here was an example of the patentee so altering the typical scope of a claim reciting "consisting essentially of" as a transitional phrase.  The opinion sets forth ample quotations from the prosecution history of the '742 patent in support of their decision, from both the applicant and patent examiner.  The opinion relies on Shire Dev., LLC v. Watson Pharms., Inc., 787 F.3d 1359, 1366 (Fed. Cir. 2015), Personalized Media Commc'ns, LLC v. Apple Inc., 952 F.3d 1336, 1339 (Fed. Cir. 2020), and Standard Oil Co. v. Am. Cyanamid Co., 774 F.2d 448, 452 (Fed. Cir. 1985), for the principle that "explanatory remarks" made during prosecution can demonstrate what an applicant "meant" by the amendment.  (Of course the converse is also true, to the extent that improvident or unclear "remarks" can produce a construction not intended or anticipated by an applicant.)

    The panel also considered the "strongest indicators" of patent owner's intention to have a "more-restrictive-than-typical interpretation of the phrase 'consisting essentially of'" to be a comparison with the asserted combination prior art, wherein the Court considered patent owner's representations during prosecution that "Dean teaches away from methods consisting essentially of administering brimonidine (i.e., methods which do not include administering other active agents)" (emphasis in opinion).  Also factoring into the panel's decision here is the use of "i.e.," where use of this abbreviation "indicates an intent to define the claimed 'methods'" to exclude other active ingredients.  The panel also found the intrinsic evidence (the prosecution history) to be incompatible with the Board's claim construction.  Nor was the panel persuaded that the existence of alternative embodiments in the '742 specification, reciting "comprising" were incompatible with the restrictive scope of the altered/amended claim language, citing TIP Sys., LLC v. Phillips & Brooks/Gladwin, Inc., 529 F.3d 1364, 1373 (Fed. Cir. 2008), and Pacing Techs., LLC v. Garmin Int'l, Inc., 778 F.3d 1021, 1026 (Fed. Cir. 2015).

    Petitioner Slayback's argument was that although Patent Owner Eye Therapies had represented to the patent examiner that their claims did not require other active ingredients this was not the same as precluding the use of such ingredients.  The panel rejected Slayback's argument that the circumstances here were analogous to the Court's decision in Aylus Networks, Inc. v. Apple Inc., 856 F.3d 1353 (Fed. Cir. 2017), based inter alia on different factual predicates.  According to the opinion:

    Given the applicant's arguments distinguishing Dean and definitional use of "i.e." to equate its claimed "methods consisting essentially of administering brimonidine" with "methods which do not include administering other active agents," (emphasis added), the appropriate interpretation of the applicant's representation that the claimed methods "do not require" agents other than brimonidine is that its claimed methods preclude the use of such agents.

    On this basis the Court reversed the Board's claim construction.

    The Court's assessment of the Board's obviousness determination was that the Board's claim construction was erroneous and "infected its obviousness analysis."  Evidence for this conclusion was the Board's reliance on other prior art directed to methods using combinations with other active ingredients in support for finding the challenged claims obvious.

    Finally, in explaining the decision to vacate and remand, the opinion states:

    We do not prejudge whether the correct claim construction permits the same factual findings or obviousness conclusion.  We do note, however, that because the Board applied an erroneous claim construction, it had no occasion to consider whether, under the prior art, a person of ordinary skill in the art would have been motivated to employ a method with the properly understood limitation signified by the '742 patent's use of "consisting essentially of."  We conclude that the appropriate course in this case, as in so many others involving a reversal of a Board claim construction, is to vacate the Board's decision and remand the matter, citing Kaken Pharma. Co., Ltd. v. Iancu, 952 F.3d 1346, 1355 (Fed. Cir. 2020).

    Eye Therapies, LLC v. Slayback Pharma, LLC (Fed. Cir. 2025)
    Panel: Circuit Judges Taranto and Stoll and District Judge Scarsi
    Opinion by District Judge Scarsi

  • Government Files Statement in Support of Preliminary Injunction Motion in Radian Memory Systems v. Samsung Electronics

    By Kevin E. Noonan —


     District Court for the Eastern District of TexasAlmost two decades ago, the Supreme Court handed down what has turned out to be one of its most significant patent decisions of this century:  eBay v. MercExchange.  The eBay case has had the effect of precluding prevailing patentees from being able to expect or rely upon obtaining an injunction against an adjudged infringer.  And it has led to the era of "efficient infringement," creating circumstances where it makes economic sense to infringe and pay the price (in patentee lost profits) for doing so rather than obtaining a license.  One of the most significant targets of this stratagem have been so-called "non-practicing entities," usually sole inventors, small companies, and universities.  These parties were castigated (unfairly) at the turn of the century (perhaps creating the climate for eBay) as being "patent trolls" (particularly in high tech industries).  The argument against this group is that they could not be irreparably harmed because royalty payments would make them whole (if they deserved recompense at all) and thus failed one prong of the (traditional) four-part test for obtaining an injunction revitalized in patent cases by the Court's eBay decision.


     Department of Justice (DOJ) SealThere have been efforts in Congress to rectify this situation, most notably the RESTORE Patent Rights Act of 2025 (and unsuccessfully, 2024), which has been introduced in the past Congress and the current one (as H.R. 1574 and S. 708).  The prospects for enactment are murky, particularly in view of the political power of the beneficiaries of the status quo.  Recently there are indications that the current administration has done a rethink about this issue, the evidence of which is the filing of a Statement of Interest under 28 U.S.C. § 517 by the Department of Justice Antitrust Division (DOJ) and the U.S. Patent and Trademark Office (USPTO) in Radian Memory Systems LLC v. Samsung Electronics Co., Ltd. before the U.S. District Court for the Eastern District of Texas, Marshall Division.  This case arose in the context of plaintiff's allegations of patent infringement (also sounding in anticompetitive activity but not antitrust, curiously) that a product standard developed by a private consortium that includes several large firms who practice the standardized technology had exercised monopsony power (see Weyerhaeuser Co. v. Ross-Simmons Hardwood Lumber Co., 549 U.S. 312, 322 (2007)) to preclude Radian's participation in the marketplace.  The DOJ and USPTO filed their Statement in support of Radian's motion for preliminary injunction regarding its technology for improved flash solid-state drives, asserting irreparable harm for loss of market opportunities and market position as a technology pioneer.  Relevant to the Statement, Samsung has opposed Radian's preliminary injunction motion, inter alia, on the grounds that as a non-practicing entity Radian can be made whole by money damages and thus will not be irreparably harmed.

    USPTO SealIn their Statement, the DOJ and USPTO focused on the second of the conventional requirements for preliminary injunctive relief: "(1) a likelihood of success on the merits; (2) a likelihood of irreparable harm (with no adequate remedy at law); (3) the balance of the hardships is in favor of the party seeking injunction; and (4) that an injunction is in the public interest," citing Winter v. Nat. Res. Def. Council, Inc., 555 U.S. 7, 20 (2008).  The Statement acknowledges the Supreme Court's holding in eBay rejecting the Federal Circuit's "general rule" that "an injunction will issue upon a finding of infringement and validity."  The Statement notes Chief Justice Roberts' concurring opinion explicating the historical reasons for the importance of injunctions in patent disputes in a "long tradition of equity practice" and that Justice Kennedy in his concurrence that historical injunction practice should be limited in instances where "a patentee's use of its patents [is] not for producing and selling goods—but instead for obtaining license fees."  In practice, according to the Statement, as a consequence of eBay the Federal Circuit has found irreparable harm in instances where "patents are hard to value and damages are difficult to calculate"

    Regarding irreparable harm and determinations thereof, the Statement then sets forth arguments why patents can be difficult to value as a unique asset in the context of decisions in several Circuit Courts of Appeal on the difficulties in assessing value.  The Statement emphasizes the loss of control, for example regarding the "scope and terms of a license" and the difficulties in calculating damages as factors for finding irreparable harm in patent and other cases from several Circuits.  Calculating patent damages for a reasonable royalty without an established royalty base has been likened to "involve more the talents of a conjurer than those of a judge," citing Fromson v. W. Litho Plate & Supply Co., 853 F.2d 1568, 1574 (Fed. Cir. 1988) (regarding "hypothetical negotiation" assessments).  These circumstances are illustrated by the outcomes of several damages determinations by the Federal Circuit and that "the difficulty in calculating monetary damages for ongoing patent infringement is evidence of irreparable harm, i.e., that legal remedies are inadequate," citing i4i Ltd. P'ship v. Microsoft Corp., 598 F.3d 831, 862 (Fed. Cir. 2010), and other cases.  And while the Court has recognized that "[e]ven without practicing the claimed invention, the patentee can suffer irreparable injury," citing Presidio Components, Inc. v. Am. Tech. Ceramics Corp., 702 F.3d 1351, 1362 (Fed. Cir. 2012), it is also the case that "the Federal Circuit has yet to find harm for patentees who rely solely on licensing, at times citing Justice Kennedy's concurrence in eBay," citing Verinata Health, Inc. v. Ariosa Diagnostics, Inc., 809 Fed. App'x 965, 976 (Fed. Cir. 2020).  Completing the litany of what the Federal Circuit has and has not done in this regard, the Statement asserts that the Court has found it to be "quite the opposite" that "the Federal Circuit has not held that an ongoing royalty can never be difficult to calculate or that it meant there could be no irreparable harm," citing ActiveVideo Networks, Inc. v. Verizon Communs., Inc., 694 F.3d 1312, 1338 (Fed. Cir. 2012), and that "the prospect of an injunction can facilitate negotiation among the parties," citing In re Mahurkar Double Lumen Hemodialysis Catheter Pat. Litig., 831 F. Supp. 1354, 1397 (N.D. Ill. 1993) (Circuit Court Judge Easterbrook, sitting by designation).

    The Statement gets to the crux of the difficulties created by eBay when it asserts that "[t]he possibility of an injunction also helps prevent potential licensees from viewing infringement as economically efficient, which would further erode the patent's value and the patentee's control over it," crediting law review articles by Kristen Osenga ("Efficient" Infringement and Other Lies, 52 SETON Hall L. Rev. 1085 (2022)) and Adam Mossoff (The Injunction Function: How and Why Courts Secure Property Rights in Patents, 96 NOTRE DAME L. REV. 1581 (2021)) for this insight as well as pre-eBay decisions from the Federal Circuit; see Hybritech Inc. v. Abbott Labs., 849 F.2d 1446, 1456-57 (Fed. Cir. 1988).  This situation affects the judicial system negatively as well according to the Statement, noting that "the chances any company will take a license are significantly reduced until a court renders a final verdict, thereby reducing incentives to settle and increasing the number and durations of cases, while also inflicting additional cost on the patent owner simply to get to that result."

    The DOJ and USPTO clarifies that it is not advocating for a particular outcome in this case but that the district court should consider, in assessing the irreparable harm prong of the preliminary injunction test, the difficulties of calculating damages in ongoing litigation as well as the effect (without having an injunction) of Radian's loss of control of its patent.  And the Statement emphasizes the importance of the other prongs of the test in the district court making a decision on whether the circumstances justify grant of Radian's motion for summary judgment.  Finally, the Statement disclaims outcomes where summary judgment provides either party (but particularly the patentee) with "leverage" in excess of what is justified by the value of the patent and accompanying value of the claimed technology by the parties.

    The eBay case joined many handed down by the Court (such as KSR Intl. v. Teleflex, In re Bilski, and Association of Molecular Pathologists v. Myriad Genetics, among others) to address the Federal Circuit's jurisprudence that, as one commentator characterized it, "quietly walked away from" Supreme Court precedent thought to be in error or outdated during the twenty-plus years where the High Court gave the new appellate court time to get its institutional legs under it.  While certainly having its desired effect (re-establishing expressly the High Court's supremacy over patent law), it is unlikely that the Justices considered what is hoped to have been the unexpected consequences of this decision and other such decisions.  The DOJ/USPTO Statement is at best a toe in the water or a trial balloon regarding administrative reactions to these consequences; Congress is where any lasting change is to be sought no matter how unlikely or protracted that process proves to be.

  • MSN Laboratories Private Ltd. v. Bausch Health Ireland Ltd. (Fed. Cir. 2025)

    By Kevin E. Noonan —

    Federal Circuit SealAs has been noted recently (Agilent Technologies, Inc. v. Synthego Corp.), fact-based decisions from the U.S. Patent and Trademark Office (typically from the Patent Trial and Appeal Board) are reviewed under the substantial evidence standard enunciated in the Administrative Procedures Act (5 U.S.C. § 706) according to the Supreme Court's decision in Dickinson v. Zurko.  The stringency of this standard of review has reduced the frequency with which the Federal Circuit has reversed (or vacated and remanded) PTAB decisions, but such decisions still exist.  The circumstances under which such consequences can arise are illustrated in MSN Laboratories Private Ltd. v. Bausch Health Ireland Ltd. (non-precedential) (wherein questions arose regarding the PTAB's factual determinations for both parties).

    The appeal arose from separate inter partes review challenges for obviousness by Mylan Pharmaceuticals and MSN Laboratories over Bausch's U.S. Patent No. 7,041,786, directed towards guanylate cyclase receptor agonist peptides, used to treat gastrointestinal disorders.  These compounds are understood to work by stimulating production of cyclic guanosine monophosphate (cGMP) which "regulates sodium and water secretion in the intestinal lumen."  Bausch sells its patented product as Trulance® "for use as an oral laxative to treat constipation."

    A relevant feature of these compounds is that they are known to exhibit topoisomerism, wherein the peptide can exist in alternate three-dimensional forms, one of which being biologically active and the other inactive.  Claim 1 of the '786 patent is reproduced in the opinion as being representative:

    1.  A peptide consisting of the amino acid of SEQ ID NO:20.

    Wherein SEQ ID NO. 20 is a synthetic analog (plecanatide) of prior art uroguanylin that differs by a single amino acid substitution (aspartic acid (Asp)-to-glutamic acid (Glu)):
    Uroguanylin: Asn1-Asp2–Asp3-Cys4-Glu5-Leu6-Cys7-Val8-Asn9-Val10-Ala11-Cys12-Thr13-Gly14-Cys15-Leu16
    Plecanatide: Asn1-Asp2–Glu3– Cys4-Glu5-Leu6-Cys7-Val8-Asn9-Val10-Ala11-Cys12-Thr13-Gly14-Cys15-Leu16
    (this substitution is termed "conservative" due to the similarities between the amino acids, i.e., differing on a single methylene (-CH2-) in the amino acid sidechain).

    MSN's IPR obviousness challenge asserted two principle references:  U.S. Patent No. 5,489,670 and a scientific publication to Li entitled "Purification, cDNA Sequence, and Tissue Distribution of Rat Uroguanylin."  MSN argued that there was motivation in the art to make the Asp->Glu substitution distinguishing plecanatide from uroguanylin because first, the '670 patent taught the use of uroguanylin for treating constipation; second, the Li reference taught that this specific amino acid substitution would produce a compound (plecanatide) "having an affinity to guanylate cyclase receptors"; and third, that the person of ordinary skill in the art would understand the conservative nature of the Asp->Glu substitution and the consequences thereof.  Bausch countered by arguing first, that the skilled worker would not have been motivated to select uroguanylin as a "lead compound" under the Federal Circuit's analytical framework for chemical obviousness (see, e.g., Otsuka Pharm. Co. v. Sandoz, Inc., 678 F.3d 1280, 1291 (Fed. Cir. 2012)).  Second, Bausch argued that there would not have been a reasonable expectation of success in making this substitution resulting in the desired biological activity.

    While the PTAB disagreed with Bausch's arguments and instituted the IPR, additional argument proffered by Bausch asserting unexpected results was persuasive during the IPR proceedings.  In its Final Written Decision, the Board found that there was motivation to select uroguanylin as the lead compound and that there would have been a reasonable expectation of success in making the aspartic acid-to-glutamic acid substitution, but that the asserted unexpected results arising from Bausch's proffered experiments outweighed MSN's prima facie obviousness case.  Importantly for the Federal Circuit's opinion, the Board asserted as its basis for this finding that this evidence "reflect[ed] the use of human uroguanylin as it naturally exists, i.e., a mixture with some interconversion between topoisomers, which is the closest prior art to the peptide of claim 1."  This appeal followed.*

    The Federal Circuit vacated the PTAB's decision and remanded, in an opinion by Judge Lourie joined by Judges Dyk and Chen.  Both parties appealed, with Bausch asking the Court to reverse the Board's finding that the skilled worker would have been motivated to select uroguanylin as a lead compound (a finding that the panel held was supported by substantial evidence).  According to Bausch's argument, the skilled worker would have chosen a different lead compound, bacterial ST peptide, which was a "far more promising option," inter alia because it did not have the topoisomerism property (wherein a portion of the compound is inactive) and it produced "'remarkabl[y]' more cGMP than uroguanylin."  The panel agreed with the Board's decision against finding the ST peptide to be the preferred lead compound because it was produced by a pathogenic bacteria and thus posed a danger in being administered to humans and that this apprehension was consistent with the disclosure in the cited prior art.  On these grounds (and because Bausch did not challenge the Board's decision regarding the reasonable expectation of success attendant upon the conservative substitution), the panel affirmed the Board's finding that MSN had established a prima facie obviousness case.

    Turning to the Board's decision that Bausch had rebutted MSN's obviousness case with a showing of unexpected results, the Federal Circuit recognized four sets of experiments proffered for this showing:

    (1) the amount of cGMP produced by each peptide at a neutral pH, (2) the amount of cGMP produced by each peptide across different pHs found in the GI tract, (3) the binding affinity of each peptide for guanylate cyclase receptors, and (4) the ratio of active to inactive topoisomers after each peptide was incubated in an acidic solution.

    Although MSN asserted four arguments in response (that the experiments did not compare plecanatide with the closest prior art; that the experiments were not "commensurate on scope"; that these experiments just showed "difference in degree" and not a "difference in kind"; and that these experiments failed to rebut their prima facie case), the panel rendered its decision solely on the first of these arguments.  The opinion asserts that the standard for establishing unexpected results is that the claimed compound must be compared with the closest prior art, citing In re Merchant, 575 F.2d 865, 869 (CCPA 1978).  Where, as here, the comparator compound can exist in two alternative forms the comparison must be between the "structurally closest" forms of the compounds under AstraZeneca Pharms. LP v. Teva Pharms. USA, Inc., 583 F.3d 766, 775 (Fed. Cir. 2009) (relying on Merchant).  One basis for MSN's argument was that plecanatide, like uroguanylin, can exist in two alternative forms, only one of which is biologically active (relying on assertions by Bausch made before the EPO) and on Bausch's challenged claims not reciting any limitations regarding the existence of such alternative forms.  MSN further argued that the experimental evidence proffered by Bausch used only the active form of plecanatide while both active and inactive forms of uroguanylin were used for comparison (despite the availability in the art of methods for producing pure biologically active forms of uroguanylin).  Under these conditions (asserted but not definitively established by MSN), MSN argued that Bausch's evidence considered by the Board did not satisfy the requirement for comparison of the lead compound with the structurally closest prior art compound.  The Board had rejected this argument from MSN, finding that there was an inevitable production of a mixture of active and inactive forms of uroguanylin and thus such mixtures were the closest prior art compounds.  The Board recognized that such a topoisomeric mixture was the comparator used in Bausch's experiments but did not make a determination regarding whether plecanatide used in those experiments interconverted between active and inactive forms (the opinion stating that "[t]hose would seem to be essential inquiries").

    Based on these considerations, the panel held that "the Board's determination that the experiments compared the claimed invention with the closest prior art lacks adequate explanation" based on three reasons.  First, the opinion states that "the Board sidestepped the critical threshold issue of whether the claims encompass plecanatide compounds in both the active and inactive forms . . . explicitly leaving open the question whether the challenged claims encompass both active and inactive topoisomers of plecanatide."  Second, the panel held that the Board had erred for failing to determine whether pure preparations of biologically active uroguanylin could be obtained suitable for comparison with putatively pure preparations of biologically active forms of plecanatide.  Third, according to the Federal Circuit the Board had not addressed whether the uroguanylin preparations used by Bausch were actually the closest prior art (based on the experimental evidence submitted by Bausch in support of its conclusions).

    The panel mandated that on remand "the Board should determine, based on the evidence put forward by the parties, whether plecanatide exhibits topoisomerism and whether the testing of the challenged claims should encompass both the active and inactive forms" and "reevaluate the experimental evidence consistent with its determination regarding what is the closest prior art compound."

    (Not limiting its discernment of error to the Board (or Bausch), the panel also found that MSN had taken "contradictory positions" regarding a prior art description of methods for determining levels of purity for the topoisomeric forms relevant to its "commensurate in scope" arguments presented to the panel.)

    The Federal Circuit recognized that resolution of these issues is necessary in order to decide whether Bausch's experiments compared its claimed plecanatide to the closest prior art, and that to the extent they do not "their value with respect to its unexpected results determination is considerably diminished."

    * Mylan separately appealed and then voluntarily dismissed its appeal according to the opinion.

    MSN Laboratories Private Ltd. v. Bausch Health Ireland Ltd. (Fed. Cir. 2025)
    Nonprecedential disposition
    Panel: Circuit Judges Lourie, Dyk, and Chen
    Opinion by Circuit Judge Lourie

  • Edwards Lifesciences Corp. v. Cardiovalve Ltd. (Fed. Cir. 2025)

    By Kevin E. Noonan —

    Federal Circuit SealOne of the assumptions, or promises, or hopes, attendant on the inauguration of post-grant review proceedings (particularly inter partes reviews) under the Leahy-Smith America Invents Act was that, as in European Opposition Proceedings, a Patent Owner would be able to propose amendments to overcome unpatentability arguments raised by Petitioners.  This was not how these reviews were implemented, however, ostensibly due to the statutorily mandated timeframe (one year from institution of the proceedings) that a European-like proceeding would not accommodate.  Accordingly, it has been rare for the Patent Trial and Appeal Board (PTAB) to grant a Patent Owner leave to file such amendments ("Over 450 such motions were decided between 2012 and 2023, and 83% of them were denied").  One of those rarae aves where the motion was granted is Edwards Lifesciences Corp. v. Cardiovalve Ltd., which in addition illustrates how such motions and the claims amendments submitted therewith can result in claims passing patentability muster.

    Petitioner Edwards Lifesciences challenged all claims of U.S. Patent No. 10,702,385 directed to methods for using a prosthetic heart valve support that provides "minimally invasive (e.g., transcatheter and/or transluminal) implantation of a prosthetic valve at a native valve of a subject."  Edwards asserted six grounds of unpatentability relying on two patents to Goldfarb, U.S. Patent Nos. 7,563,267 and 7,635,329.  As explained in the opinion, these patents disclosed a particular prosthetic heart valve support identified in the opinion as embodiment A:

    Image 1
    Image 2Relevant elements disclosed in the Goldfarb patents include (as illustrated in the drawings) "a 'fixation device' (depicted in Fig. 22A–22B [above] as element 14) [that] has 'distal and proximal elements' (elements 18 and 16 respectively) on each side of the fixation device that can move towards each other to capture tissue flaps and 'lateral branches' (elements 19A, 19B) and/or the distal elements (element 18) that can move independently of each other."  Coupling member 19 in the Figures "is bifurcated into two resilient and flexible branches 19A, 19B" that can move from the position shown in Fig. 22A to the one shown in Fig. 22B below:

    Image 3
    The opinion explains that Goldfarb describes "fixation device 14 [being] coupled to the shaft 12 by a coupling mechanism," wherein "[o]ne embodiment of the coupling mechanism includes 'an upper shaft 20 and a detachable lower shaft 22 which are interlocked at a joining line or mating surface 24."  Another feature of the Goldfarb device is a "sigmoid curve defining a male element and female element" on the upper shaft of coupling member 19 which 'interlock respectively with corresponding female and male elements' on the lower shaft."

    The Board instituted the IPR and a little less than three months thereafter Patent Owner Cardiovalve file its Motion to Amend (and a little more than six months later a Revised Supplemental Motion to Amend), clarifying that its motion was not contingent and cancelling the ten challenged claims in lieu of substitute claims 11-20.  Claim 11 set forth below is written here to identify with italics the change in original independent claim 1:

    11.  A method for use at a native valve of a heart of a subject, the valve including a first leaflet and a second leaflet, the method comprising:
        transluminally advancing, to the heart, an implant coupled to a delivery apparatus,
            the implant including a first clip, a second clip, and a support portion flexibly coupled to the first and second clips, the support portion having an opening that surrounds a central longitudinal axis of the implant, the first clip and the second clip fixedly coupled to each other, the first clip including a first-clip arm, and the second clip including a second-clip arm, the first-clip arm and the second-clip arm each having an end most displaceable from the central longitudinal axis of the implant, and
            the delivery apparatus including a delivery tube and at least one clip controller disposed within the delivery tube,
                the first-clip arm, the second-clip arm, and the support portion being disposed within the delivery tube during the transluminal advancing to the heart;
        advancing the implant out of the delivery tube by advancing the end of the first-clip arm and the end of the second-clip arm out of the delivery tube before advancing the support portion out of the delivery tube;
        forming the first leaflet and the second leaflet into a double-orifice arrangement by using the implant to couple a middle scallop of the first leaflet to a middle scallop of the second leaflet by, using the clip controller:
            opening the first clip by deflecting the first-clip arm;
            independently of opening the first clip, opening the second clip by deflecting the second-clip arm;
        gripping the first leaflet with the first clip by closing the first clip by deflecting the first-clip arm; and
            independently of gripping the first leaflet, gripping the second leaflet with the second clip by closing the second clip by deflecting the second-clip arm;
        decoupling the clip controller from the implant; and
        withdrawing the delivery apparatus from the subject.

    The Board granted Cardiovalve's motion, which perforce occasioned judgment against Edwards, because the basis of the motion grant was that Edwards had not shown by a preponderance of the evidence that the substitute claims were unpatentable.  This appeal followed.

    The Federal Circuit affirmed, in an opinion by Judge Cunningham joined by Chief Judge Moore and Judge Hughes.  The opinion informs that the error raised by Edwards in the appeal were related to these claim elements:

    (1) "a support portion flexibly coupled to the first and second clips, the support portion having an opening that surrounds a central longitudinal axis of the implant" (the "support portion" limitation); and (2) "advancing the implant out of the delivery tube by advancing the end of the first-clip arm and the end of the second-clip arm out of the delivery tube before advancing the support portion out of the delivery tube" (the "advancing" limitation).

    Specifically, Edwards raised five arguments that the Board erred:

    (1) adopting an implicit construction of "support portion" that excluded the male element portion of the coupling member; (2) finding that Goldfarb's male element does not have an opening that "surrounds" the central longitudinal axis of the fixation device; (3) finding that Goldfarb does not disclose or render obvious the "advancing" limitation, i.e., that the ends of the clip arms are advanced out of the delivery tube before the support portion; (4) finding that Goldfarb's collar does not satisfy the "support portion" limitation; and (5) misconstruing "advancing" and "having an end most displaceable."

    The opinion states that Edwards asserted only the first, fourth, and fifth arguments at oral argument.

    Regarding Edwards' argument that the "implicit construction" of the term "support portion" excluded the "male element" of the coupling member, the panel agreed with Cardiovalve's characterization of the Board's decision as being a factual finding and not part of claim construction.  These factual findings included that "the male element of the coupling member alone does not constitute a support portion" but that the coupling member was "plainly a single, unitary structure."  According to the opinion, all the illustrated elements performing the ascribed function were not separate as argued by Edwards but "together form a solid, single component" (emphasis in opinion).  The opinion relies on Trading Techs. Int'l, Inc. v. Open E Cry, LLC, 728 F.3d 1309, 1319 (Fed. Cir. 2013), for the distinction that the Board was not "directed towards 'discern[ing] the meaning of a particular term'" and accordingly had engaged in factfinding (reviewed for substantial evidence) rather than claim construction (reviewed de novo).  Under the proper standard, the Federal Circuit found the Board's decision was supported by substantial evidence and accordingly affirmed.

    For the Edwards' second argument, that the Board erred regarding the collar element 131 illustrated above not being a support portion, the panel held that according to the plain language of substitute claim 11 the support portion is required to be coupled to the first and second clips when the implant is advanced and that substantial evidence supported the Board's finding that Goldfarb's collar does not constitute the claimed support portion.  The Board's interpretation was supported in the panel's opinion by the Goldfarb disclosure that "the collar and coupling member can freely move with respect to each other," and thus "Goldfarb's collar 'cannot provide the support functions' required of a support portion."  The Board also rejected Edwards' argument that "the collar may eventually be permanently coupled to the clips" in use because at the time the implant was delivered the collar is not so coupled (and once again the plain language of substitute Claim 11 requires it to be so).  The Federal Circuit held that, using the plain language of substitute claim 11, the Board's decision that the cited art did not render these claims unpatentable was supported by substantial evidence.

    The panel considered Edwards's final argument as having two aspects:  first, that the Board erred in construing the "advancing" limitation; and second, that under the proper construction the Board's determination that the Goldfarb reference did not disclose (and thus render obvious) claims reciting the "advancing" limitation was error.  On the first aspect of this argument, Edwards argued that under the Board's erroneous construction what construed "advancing" encompassed the end of the clips to "precede any part of the support portion, not the entire support portion, when advanced'" (emphasis in opinion).  In Edwards' view, the proper construction required the entire support portion to be delivered from the delivery tube element.  Cardiovalve agreed with the Board, that whatever was advanced it just need to "begin[ ] to emerge from the delivery tube."  Again relying on the plain and ordinary meaning standard for construing claim terms, the panel held that such language indicated that "the support portion must only be partially advanced out of the delivery tube."  The opinion set forth an illustration from the '385 patent specification in support of this interpretation:

    Image 4
    wherein "the clip arms emerge in their entirety, while the prosthetic valve support 22, which includes the support portion 60, is only partially out of the delivery tube."

    With regard to the second aspect of Edwards' argument, the panel agreed with Cardiovalve's argument that as a consequence of the Board's construction of the "advancing" term the collar and coupling member recited in substitute claim 11 could not meet that limitation.  Specifically, "flexible arms 19A and 19B (which are part of coupling member 19) are attached to the bases of both proximal and distal elements 16 and 18 and must therefore be advanced from the delivery tube as the clips begin to emerge."  The Federal Circuit held that Edwards' arguments were "largely speculative" and based on how Edwards interpreted the Figures set forth in the Goldfarb reference and that these Board findings were supported by substantial evidence.  On that basis the Court affirmed the Board.

    A lesson to be learned from this decision is that while it may be an unlikely eventuality for the Board to grant a motion to amend claims involved in an IPR all that effort will be for naught unless the amended claims overcome the patentability challenge raised by Petitioner.  And any such amendments must be supported by the specification of the challenged patent(s).  While achieving these goals may resemble an extensive juggling act concerning understanding of the prior art, anticipating how that prior art may be asserted in a patentability dispute, and claiming accordingly is just another complication in competent patent prosecution; in other words, as Branch Rickey said in another context, "Luck is the residue of design."

    Edwards Lifesciences Corp. v. Cardiovalve Ltd. (Fed. Cir. 2025)
    Nonprecedential disposition
    Panel: Chief Judge Moore and Circuit Judges Hughes and Cunningham
    Opinion by Circuit Judge Cunningham

  • Agilent Technologies, Inc. v. Synthego Corp. (Fed. Cir. 2025)

    By Kevin E. Noonan —

    Federal Circuit SealAn argument could be made that one of the most significant Supreme Court decisions in U.S. patent law in the last thirty years was Dickinson v. Zurko.  In that case the Court held that the Federal Circuit was bound by the provisions (5 U.S.C. § 706) of the Administrative Procedures Act to defer to factual determinations made by administrative agencies within the area of their expertise.  (It should be understood that the Supreme Court's more recent decision in Loper Bright Enterprises v. Raimondo did not disturb this statutory standard, being limited to agency interpretations of the laws under which they were established or administered.)  The effects of this interpretation of the laws governing judicial review can be observed (and have been amplified) in the Federal Circuit's opinions regarding Patent Trial and Appeal Board decisions, particularly as applied in inter partes review (IPR).  The most recent application of this standard can be found in Agilent Technologies, Inc. v. Synthego Corp.

    Synthego challenged two Agilent patents in its IPRs:  U.S. Patent Nos. 10,337,001 and 10,900,034. These patents were directed to CRISPR-Cas9* systems for gene editing.  Claim 1 in each of these patents are set forth in the opinion:

    The '001 patent:

    A synthetic CRISPR guide RNA having at least one 5′-end and at least one 3′-end, the synthetic guide RNA comprising:
        (a) one or more modified nucleotides within five nucleotides from said 5′-end, or
        (b) one or more modified nucleotides within five nucleotides from said 3′-end, or
        (c) both (a) and (b);
        wherein said guide RNA comprises one or more RNA molecules, and has gRNA functionality comprising associating with a Cas protein and targeting the gRNA:Cas protein complex to a target polynucleotide, wherein the modified nucleotide has a modification to a phosphodiester linkage, a sugar, or both.

    (emphasis added).

    The '034 patent:

    A synthetic CRISPR guide RNA comprising:
        (a) a crRNA segment comprising (i) a guide sequence capable of hybridizing to a target sequence in a polynucleotide, (ii) a stem sequence; and
        (b) a tracrRNA segment comprising a nucleotide sequence that is partially or completely complementary to the stem sequence,
        wherein the synthetic guide RNA has gRNA functionality comprising associating with a Cas protein and targeting the gRNA:Cas protein complex to the target sequence, and comprises one or more modifications in the guide sequence, wherein the one or more modifications comprises a 2′-O-methyl.

    (emphasis added).

    The opinion characterizes as "[t]he key prior art" supporting Synthego's challenge on anticipation grounds to be an International Application, published as International Publication No. WO 2015/026885, filed on August 20, 2014 by Pioneer Hi-Bred International. This application disclosed "compositions and methods" for performing CRISPR featuring "guide polynucleotide[s]["gRNA"]" in both single- and dual-molecule forms; specific disclosure included Example 4, for modifying the nucleotide base, phosphodiester bond linkage or molecular topography of the guiding nucleic acid component(s) of the guide polynucleotide/Cas endonuclease system" "for increasing cleavage activity and specificity."  Also disclosed were modified RNA molecules comprising "nucleotide and/or phosphodiester bond modifications [that] may be introduced to reduce unwanted degradation."  With regard to Synthego's contentions of invalidity for obviousness, two additional references were asserted:  a first scientific publication by Threlfall et al. (2011, Synthesis and Biological Activity of Phosphonoacetate- and Thiophosphonoacetate-modified 2′-O-methyl Oligoribonucleotides, 10 Org. Biomol. Chem. 746–54) and a second scientific publication by Deleavey et al. (2012, Designing Chemically Modified Oligonucleotides for Targeted Gene Silencing, 19 Chem. & Bio. Review 937–54).  The Threlfall reference discloses specific nucleotide modifications using PACE (phosphonoacetate)- or thioPACE (phosphonothioacetate)-modified phosphate groups, and the Deleavey reference discloses "a vast array" of nucleotide modifications to stabilize oligonucleotides (including RNA oligonucleotides).

    The PTAB found all claims in each patent to be unpatentable.**  The Board found that the Pioneer Hi-Bred reference disclosed a functional gRNA and was enabling, and that those claims that were not anticipated were obvious.  This appeal followed.

    The Federal Circuit affirmed, in a decision by Judge Prost, joined by Judges Linn and Reyna.  In announcing the "substantial evidence" standard for the Board's factual determinations (which included anticipation, citing St. Jude Med., LLC v. Snyders Heart Valve LLC, 977 F.3d 1232, 1238 (Fed. Cir. 2020)), the opinion relies on In re Bayer Aktiengesellschaft for the principle that "[w]here two different conclusions may be warranted based on the evidence of record, the Board's decision to favor one conclusion over the other is the type of decision that must be sustained by this court as supported by substantial evidence," 488 F.3d 960, 970 (Fed. Cir. 2007) (emphasis added).

    Agilent propounded three arguments in its appeal:  first, that the Board's anticipation determination was not supported by substantial evidence; second, that the Pioneer Hi-Bred application was not enabling; and third, that the skilled worker would not have had a reasonable expectation of success (with regard to the Board's obviousness determinations) that the PACE and thioPACE modifications would have been successfully used to modify gRNA in a CRISPR-Cas9 system.  Regarding Agilent's first argument, the panel determined that the Board's anticipation decision was supported by substantial evidence.  The opinion enumerates the facts the Board relied upon concerning the Pioneer Hi-Bred disclosure:

    "Pioneer Hi-Bred discloses that the guide polynucleotides described therein can: (1) form a complex with a Cas endonuclease; and (2) enable the endonuclease to recognize a DNA target site.  That disclosure reads on both the associating and targeting aspects of the 'gRNA functionality' recited" in the challenged claims.

    Examples 4 and 5 of the Pioneer Hi-Bred disclosure were specifically called out in the opinion for referring to "modified guide nucleotides," which the Board interpreted as "indicating that those sequences have [the claimed gRNA] functionality," supported by several additional statements in the Pioneer Hi-Bred disclosure.  The Board had rejected (and the Federal Circuit affirmed as being supported by substantial evidence) Agilent's argument that the purported lack of cleavage activity using such modified gRNA nucleotide "demonstrate[d] that Pioneer Hi-Bred does not disclose gRNA functionality," based in part on admissions by Agilent's expert that "just because a gRNA in Table 4 [in Pioneer Hi-Bred] lacks cleavage activity does not demonstrate that it also lacks the ability to bind a Cas protein and target that complex to target polynucleotide."  Taken in its totality, the panel held that the Board's decision that the Pioneer Hi-Bred application anticipated certain of the claims of the '001 and '034 patents was supported by substantial evidence.

    The opinion then turns to Agilent's argument that the disclosure of the Pioneer Hi-Bred application was not enabling, where the panel "[saw] no error" in the Board's conclusion that the reference was enabling.  One basis for the Court's decision in this regard was recognition that for assertion as an anticipating reference only an enabling disclosure, not evidence of actual reduction to practice is required, under inter alia, Schering Corp. v. Geneva Pharms., 339 F.3d 1373, 1380 (Fed. Cir. 2003); Rasmusson v. SmithKline Beecham Corp., 413 F.3d 1318,1326 (Fed. Cir. 2005); and In re Morsa, 803 F.3d 1374, 1376 (Fed. Cir. 2015) (cited in the opinion).  Moreover "[p]rior art disclosures are presumed enabling" under Impax Labs., Inc. v. Aventis Pharms., Inc., 545 F.3d 1312, 1316 (Fed. Cir. 2008), according to the opinion.  The panel appreciated that the Board performed its enablement assessment under the conventional rubrics set forth in In re Wands, 858 F.2d 731 (Fed. Cir. 1988), and that the Pioneer Hi-Bred disclosure passed muster under those standards (while recognizing that certain disclosures, including Examples 4 and 5 were prophetic).  Regarding the relative novelty of CRISPR-Cas9 systems when the Pioneer Hi-Bred application was filed the Board stated that:

    [W]hile the art was somewhat unpredictable in December 2014, it was far from a blank slate with a [person of ordinary skill in the art] understanding how the different elements of a CRISPR/Cas system are used and function together, including the role of gRNA; the types of chemical modifications that had been successfully used in other systems to reduce RNA degradation, while preserving functionality; and standard techniques for making gRNAs with the modifications disclosed and exemplified in Pioneer Hi-Bred.

    The Federal Circuit in affirming the Board's holding that the Pioneer Hi-Bred disclosure was enabling rejected Agilent's argument that the factual circumstances in the Court's Impax decision were analogous.  There the issue was enablement of a disclosure of "hundreds or thousands of compounds and several diseases," as well as "broad and general" dosage guidelines "without sufficient direction or guidance to prescribe a treatment regimen, whereas here "Pioneer Hi-Bred exemplifies particular crRNA sequences having the recited chemical modifications at the recited locations and teaches that gRNA comprising such may be used as guide polynucleotides in a CRISPR Cas system."  In addition the Board had supported its enablement holding because "the particular types of chemical modifications disclosed in Pioneer Hi-Bred and recited in the challenged claims had been known and used for decades to stabilize RNA against unwanted degradation in other systems."  Also unavailing was Agilent's reliance on the Supreme Court's Amgen Inc. v. Sanofi decision, the opinion noting distinctions "in two meaningful ways."  First, the Court's Amgen decision involved "whether the asserted claims were sufficiently enabling to be valid under 35 U.S.C. § 112, not whether a prior-art reference was enabling and could thus support anticipation," which are "two separate inquiries," citing Novo Nordisk Pharms., Inc. v. Bio-Tech. Gen. Corp., 424 F.3d 1347, 1355 (Fed. Cir. 2005).  According to the panel, enablement under Section 112 requires a disclosure to enable the skilled worker to be able to use the claimed invention, whereas for Section 102 purposes no such disclosure of utility is required.  Second, the Board found that the Pioneer Hi-Bred disclosure would have been understood by the person of ordinary skill in the art with regard to "how the different elements of a CRISPR/Cas system are used and function together, including the role of gRNA; the types of chemical modifications that had been successfully used in other systems to reduce RNA degradation, while preserving functionality; and standard techniques for making gRNAs with the modifications disclosed and exemplified in Pioneer Hi-Bred" and that this disclosure was enabling.  In addition, the Federal Circuit rejected Agilent's argument regarding Pioneer Hi-Bred's purported disclosure of "many inoperable guide [RNAs]" because the data Agilent relied upon for this argument related to synthetic DNA sequences not modified RNA recited in the challenged claims.  The last specific Agilent argument rejected by the Board and affirmed by the panel was that the Pioneer Hi-Bred disclosure did not enable a "single guide RNA" (sgRNA), which according to the opinion was expressly disclosed in the reference.

    Finally, the opinion assessed and rejected Agilent's arguments that the Board erred in finding certain other claims in each patent to be invalid for obviousness.  The grounds for these arguments was that the Pioneer Hi-Bred disclosure "did not expressly disclose the functionality of the claimed PACE- or thioPACE-modified guides" and that the Board did not explain its findings regarding there being a reasonable expectation of success.  Regarding the former argument, the opinion states that Agilent conflated the requirements for anticipation with those for obviousness, wherein the lack of PACE- or thioPACE-modified guides disclosure in the Pioneer Hi-Bred reference was remedied by combination with the Threlfall and Deleavey disclosures, as supported by expert testimony adduced by Synthego.  Regarding Agilent's latter argument, the panel considered as "thorough" the Board's analysis that the person of ordinary skill would have reasonably expected success from the combination of the Pioneer Hi-Bred reference with either the Threlfall or Deleavey disclosures.  The opinion sets forth the Board's reasoning to illustrate its decision to affirm:

    [B]y December 2014, several studies had shown that the CRISPR/Cas system could successfully tolerate modifications.  While these studies describe different types of modifications than those in the challenged claims, such evidence nevertheless supports Dr. Furneaux's testimony that a [person of ordinary skill in the art] would have expected that chemical modifications could be made at the 5[′] and 3[′]-ends of a gRNA while preserving the Cas enzyme's gene editing function.

    The record further demonstrates that shortly after the discovery of the CRISPR/Cas system for gene editing and prior to December 2014, there were already a number of researchers in addition to the authors of the Pioneer Hi-Bred publication suggesting the use of the claimed chemical modifications to improve the resistance of gRNA to degradation.  [Agilent's] expert, Dr. Marshall, conceded as much on cross-examination.  The fact that multiple groups of researchers independently suggested the same types of gRNA modifications re cited in the challenged claims evidences that a [person of ordinary skill in the art] would have had a reasonable expectation those modifications could be successfully employed in a CRISPR/Cas system.  Moreover, while [Synthego] points to multiple references suggesting such modifications to gRNA, neither [Agilent] nor Dr. Marshall identify any reference expressing doubt that such modifications could be successfully implemented in a CRISPR/Cas system.  This contrast undermines [Agilent's] argument that a [person of ordinary skill in the art] would not have reasonably expected the prior art modifications to work in a CRISPR/Cas system.

    This record was sufficient for the Federal Circuit to affirm the Board's decision as being supported by substantial evidence.

    Agilent Technologies, Inc. v. Synthego Corp. (Fed. Cir. 2025)
    Panel: Circuit Judges Prost, Linn, and Reyna
    Opinion by Circuit Judge Prost

    * The opinion in a footnote informs that "CRISPR" stands for "clusters of regularly interspaced short palindromic repeats."

    ** Claims 1–7, 9, 10, 12–15, 17, 18, 20–25, and 27–30 of the '001 patent and claims 1–5, 8–21, and 24–33 of the '034 patent were anticipated, and claims 8, 11, 16, 19, and 26 of the '001 patent and claims 6, 7, 22, and 23 of the '034 patent were obvious over the cited references.

  • Subject Matter Eligibility in the 21st Century: Echoes of pre-§ 103 Obviousness*

    By Kevin E. Noonan —

    The evolution of subject matter eligibility after the Supreme Court's decisions in Prometheus v. Mayo, Alice v. CLS Bank, and Association for Molecular Pathology v. Myriad Genetics has resulted in a regime of predictable unpredictability and certain uncertainty (a recent cogent treatment of the phenomenon in computer science technology patenting can be found in "The Narrow Pathway to Patent Eligibility in the Federal Circuit").  The situation is reminiscent of the state of obviousness in mid-Twentieth century prior to enactment of § 103 of the patent statute, when whether a patented invention was protected was a matter of judicial subjectivity.  As a consequence and as recognized by Justice Jackson, "the only patent which is valid is one which this court has not been able to get its hands on," Jungerson v. Ostby, 335 U.S. 560, 571 (1949).

    A brief survey of seminal obviousness cases illustrated this similarity:

    • Hotchkiss v. Greenwood (1850) standard:  an inventor's invention must have "more" than what an "ordinary or skillful mechanic" would provide.

    • Cuno Engineering Corp. v. Automatic Devices Corp. (1941):  the inventive act had to come into the mind of an inventor in a "flash of genius" and not as a result of tinkering.  "The new device, however useful it may be, must reveal the flash of creative genius, not merely the skill of the calling."

    • Graham v. John Deere (1966):  interprets the statute to conform to the Court's requirements that a patentable invention must be distinguished over the relevant prior art.

    • Sakraida v. Ag Pro, Inc. (1976):  necessary to show some "synergy" between those known elements and denied patentability because the invention "simply arrange[d] old elements with each performing the same function it had been known to perform."

    • Sakraida expressly disregarded by Federal Circuit in Stratoflex, Inc. v. Aeroquip Corp. (Fed. Cir. 1983):  "[a] requirement for 'synergism' or a 'synergistic effect' is nowhere found in the statute . . . virtually all patents are 'combination patents,' if by that label one intends to describe patents having claims to inventions formed of a combination of elements."

    • "Teaching, Suggestion, or Motivation" (TSM) test developed by Federal Circuit, set aside by Supreme Court in KSR v. Teleflex but based on Graham and tied to the statute and prior art.

    Even the semantics of subject matter eligibility (SME) determinations and their analysis conjures the subjectivity and uncertainties of obviousness; how more defined or reliable is the existence of an "inventive concept" and the "flash of genius," "synergy," or something "more" that the endeavors of an "ordinary mechanic"?  The history of how the Patent Office, Patent Trial and Appeal Board, numerous district courts, and the Federal Circuit have implemented the two-part Mayo/Alice test shows that subjectivity and unreliability.  It isn't far-fetched to consider that these consequences are not definitive for the same reasons obviousness without reliance on prior art was subject to subjective considerations (hindsight in obviousness); it is often more productive to recognize a "know it when you see it" approach ala Justice Potter Stewart (on entirely different circumstances and subject matter).  Indeed, one of the organizing principles (to the extent they can be understood) of subject matter ineligibility is often based on overbroad claiming (as in Morse v. O'Reilly, a case cited in support of SME deficiencies that had been better recognized for over a century as having failed to satisfy the disclosure requirements under Section 112).

    The history of Federal Circuit jurisprudence (that has led some members of that Court to bemoan the outcome of these cases; see Judge Moore's dissent in Athena Diagnostics, Inc. v. Mayo Collaborative Services, LLC ) are set forth below:

    Table 1
    Table 2
    There are some certainties in these cases, nevertheless.  For example, diagnostic methods are almost per se ineligible.  There has been some eligibility traction in formulating claims based on natural laws in the context of a novel assay employing the natural law in certain situations; however, the consequences can be relying on new assays for each circumstance and avoiding "routine, well-understood, and conventional" assays.  More frequently claims are drafted in the context of a method of treatment informed by the results of diagnostic assay (see "Natural Alternatives International, Inc. v. Creative Compounds, LLC (Fed. Cir. 2019)" and "Endo Pharmaceuticals Inc. v. Teva Pharmaceuticals USA, Inc. (Fed. Cir. 2019)").  Such claims are susceptible to two well-recognized caveats:  inherent prior art anticipation (when individuals identified as treatment recipients received drug prior to development of the diagnostic assay; novel pharmaceuticals can avoid this outcome), and the "divided infringement" problem, when infringement is effectuated by separate practitioners of the recited limitations of the treatment method (wherein, for example, who administers the test is different from who administered the treatment and either actor cannot be characterized as being under the "direction and control" of the other).  The most coherent calculus for method claims to pass SME muster was enunciated by Judge Lourie in his Vanda decision, illustrating the advantages of claiming specifically and thereby avoiding overbreadth:

    At bottom, the claims here are directed to a specific method of treatment for specific patients using a specific compound at specific doses to achieve a specific outcome.  They are different from Mayo.  They recite more than the natural relationship between CYP2D6 metabolizer genotype and the risk of QTc prolongation.  Instead, they recite a method of treating patients based on this relationship that makes iloperidone safer by lowering the risk of QTc prolongation.  Accordingly, the claims are patent eligible [emphasis added].

    Similarly, natural products are per se generally ineligible, although Cellzdirect and Illumina decisions suggest isolated natural product having specific utility not possessed by product in nature may be eligible when properly/adequately claimed.  Generally, formulations and combinations not arising in nature can be eligible and while databases of biological information are often per se ineligible, their use may be (as in XY).

    An Illustration of when formulations have failed to be eligible is Chromadex v. Elysium Health (Fed. Cir. 2023) (which is explained at least in part as being granted in 2005, prior to the imposition of current standards of SME).  The claims of U.S. Patent No. 8,197,807 are directed to dietary supplements comprising nicotinamide ribonucleotide, converted in vivo to NAD+, a co-enzyme involved in redox reactions:

    Image 1Claimed were compositions formulated with other components as set forth in the table (reproduced in the opinion), which had in common many similarities to milk except for the limitation that the nicotinamide ribonucleotide ([NR]) was isolated.  The Federal Circuit's analysis resembled in many respects an obviousness assessment and characterized the claims as "reading on" milk with the exception that [NR] is "isolated."  But under Myriad being "isolated" is not enough (in contrast to the state of SME when these claims were prosecuted under, inter alia, In re Bergy).  The opinion also noted that the claims were "very broad," consistent with overbreadth being a hallmark of claims failing to recite eligible subject matter, and with the distinctions with Natural Alternatives Int'l, Inc. v. Creative Compounds, LLC, where the Court recognized that claims to a natural product (beta-alanine) were patent-eligible for reciting "specific treatment formulations that incorporate[d] natural products" and that those formulations "ha[d] different characteristics and c[ould] be used in a manner that beta-alanine as it appears in nature cannot."

    Image 2To the extent a claiming strategy can be elucidated from these cases it might be to assiduously avoid overbroad claiming, based on current application of Section 112 criteria (Judge Lourie's Vanda specificity example).  A useful analogy might be to adopt a "pointillist approach" that avoids overbreadth and preemption by reciting a plurality of narrow claims directed to specific embodiments, as illustrated by Georges Seurat's "A Sunday Afternoon on the Island of La Grande Jatte" (also analogous to Twentieth Century television transmission; see "The Last Lone Inventor" for further descriptions).

    Image 3
    There is another way to look at the issue of SME and the 'judicial exceptions" contained in Shahshahani, "Against the abstract ideas exclusion," 40 Berkeley Technology Law Journal (forthcoming 2025).  In this paper the rationales for SME are applied to conventional abstract ideas and natural laws and found wanting.  Rather than accepting the conventional wisdom for the need to protect inventions that are "building blocks" due to perceived risks of inhibiting future innovation (by preemption), Professor Shahshahani argues that such building block inventions are important to incentivize by patents because their recognition and the application of natural laws and abstract ideas provides the capacity for development of future inventions employing them.  One illustration of this analysis is that while natural law often predates human discovery of it and could fall under the eligibility limitations in Parker v. Flook, human knowledge of the law provides the opportunity and ability to apply such natural laws and thus the applications thereof should not be precluded from eligibility.  The deficiencies of the conventional rationale for the judicial exceptions are further developed by recognizing that evidence supporting the conventional wisdom regarding preemption is not always correct, citing evidence that patents on genes did not inhibit genetic research, as shown by Bhaven Sampat & Heidi Williams, How Do Patents Affect Follow-On Innovation? Evidence from the Human Genome, 109 AMER. ECON. REV. 203, 217-19, 232 (2019) (existence of "gene patents" did not inhibit genetic research ) and Janet Freilich & Sepehr Shahshahani, Measuring Follow-On Innovation, 52 RES. POL'Y 104854 (2023) (finding that gene patents close to expiration caused an increase in follow-on research but those that were far from expiration had no effect).  This scholarship suggests that a reevaluation of the premises upon which the exceptions (natural laws, natural phenomena, abstract ideas) are based ("tying up" and thereby inhibiting fundamental building blocks necessary for future innovation) should be reconsidered for not being valid and not having the deleterious effects ascribed to them.  While perhaps not being (at the present time) a strategy for successfully arguing patent eligibility before the PTO or a district court in the absence of the Supreme Court addressing SME concerns (having denied certiorari to do so in almost 100 cases), further empirical evidence on the continued viability of SME restrictions may someday spur a necessary and beneficial reassessment.

    * Taken from a presentation at the American Conference Institute's 23rd Annual Advanced Summit on Life Sciences Patents, presented on May 19th, 2025 in New York City.

  • Dancing with Abstract Ideas: Patent Eligibility in 2025

    By Michael Borella —

    2025-06-09 ImageIn June 2014, the U.S. Supreme Court handed down Alice Corp. v. CLS Bank Int'l, establishing a now-infamous two-step, judicially-imposed test for patent subject-matter eligibility that narrowed the broad statutory eligibility principles set forth in 35 U.S.C. § 101.  Under Alice, one must first determine whether a patent claim is directed to an ineligible concept such as an abstract idea, a law of nature, or a natural phenomenon.  If so, the second step requires further determination of whether the claim as an ordered combination amounts to significantly more than just the ineligible concept.  In theory, this framework was meant to prevent the sweeping preemption of fields of technology that ostensibly should remain in the public domain.  In practice, however, the Alice test has proven exceedingly difficult to apply consistently, especially for software inventions.  Despite software having a concrete manifestation on physical media and being used to change the state of tangible devices, it often gets lumped into the abstract idea category even when claimed so narrowly that it can only preempt a specific use case.

    The disarray is such that even older precedents that were once shining examples of eligibility have been thrown into doubt.  The Supreme Court's own 1981 Diamond v. Diehr decision, which upheld the eligibility of a patent on a computer-implemented rubber curing process, was reaffirmed as good law in Alice.  Yet, the Alice test as currently applied could easily be used to argue that Diehr's claims are actually ineligible.[1]  This uncertainty has real-world consequences, raising the risk and cost for small and mid-sized companies seeking to protect their innovations.

    If Alice set the stage, the U.S. Court of Appeals for the Federal Circuit — the court that hears all patent appeals from district courts and the United States Patent and Trademark Office (USPTO) — has written the chapters that followed.  The last decade has seen the Federal Circuit dramatically narrow the scope of patent-eligible software, decision by decision.  First, many business methods were declared ineligible, then more and more software inventions implemented on a general-purpose computer, then even software on any platform, and eventually some non-software innovations got swept up as well.

    This tightening chokehold is reflected in the Federal Circuit's own track record.  In 2024, for example, the Federal Circuit decided 22 patent cases on substantive grounds of § 101 and found the claims eligible in only one.[2]  In other words, a staggering 95.5% effective invalidity rate of patents on appeal.  For patent owners, the Federal Circuit has become an abattoir for software patents, with only the rarest of claims surviving.

    On the front lines of patent eligibility, the USPTO has tried to bring some stability to the chaos.  The USPTO periodically issues guidance to help examiners (and applicants) navigate the morass of § 101 case law.  A notable effort was the January 2019 Revised Patent Subject Matter Eligibility Guidance, which categorized abstract ideas into three buckets (mathematical concepts, methods of organizing human activity, and mental processes) and instructed examiners to consider a claim to recite an abstract idea only if it falls into one of those recognized categories.  The 2019 guidance also introduced the notion of considering whether a claim involving an abstract idea integrates it into a practical application.  If the claimed invention is applied in a specific manner that improves technology or another field, it might be deemed patent-eligible at step one despite involving an abstract idea.  This gave applicants new arguments to overcome rejections by pointing to technological benefits in their inventions.

    By many accounts, the 2019 guidance somewhat reined in the wild inconsistency of examiner decisions and led to a modest increase in software patent allowances . . . for a while.[3]  However, unpredictability still rules the USPTO's application of Alice, especially across different examiner art units.  Some examiners (particularly in business-method oriented units) continue to issue near-automatic § 101 rejections, while others in computer hardware, software, and communications art units might be more receptive if the applicant articulates a clear technical improvement.  Appeals to the Patent Trial and Appeal Board (PTAB) are often an uphill battle — recent statistics show the PTAB affirms examiners' § 101 rejections about 90% of the time.[4]  In effect, unless you can fit your claim into the mold of a past case found eligible or an example from USPTO guidance, the safer bet is that the PTAB will say "no patent for you."

    The subjective nature of Alice leaves room for reasonable minds to differ.  And they do.  The experience of practicing before the USPTO can feel like trying to shoot at a moving target.  Even after the 2019 guidance, applicants faced divergent outcomes on similar inventions.  Examiners have significant discretion in characterizing what a claim is "directed to" at step one and what counts as "conventional" at step two.  Thus, a savvy applicant must preemptively stack the deck in their favor through careful drafting (more on that below).

    In late 2023 and 2024, the USPTO began grappling with how emerging technologies like artificial intelligence (AI) fit into the eligibility framework.  Under a mandate from former President Biden's 2023 Executive Order on AI, the USPTO issued an Updated Subject Matter Eligibility Guidance in July 2024 focusing on AI-related inventions.  Many had hoped this update — the first in almost five years — would address some of the widely voiced concerns about the unpredictability of examining AI and software inventions. Unfortunately, the 2024 Guidance dashed those hopes.[5]

    The update largely restated generic eligibility principles and added only a few AI-specific examples.  Even worse, the guidance arguably doubles down on a hardline approach suggesting that advances in AI and uses of AI are likely ineligible unless they are implemented in specific hardware circuitry or cause a significant change to the state of an ancillary system.  In other words, merely improving an AI algorithm in software might not satisfy the USPTO's idea of a practical application unless you tie it to a particular machine or a real-world effect, even if that improvement saves massive amounts of compute and storage capacity on the algorithm's host computer.

    The Supreme Court, for its part, has repeatedly declined to hear new patent eligibility cases that might clarify the doctrine.  This includes denying certiorari in 2022's American Axle case, which many hoped would address the Federal Circuit's overly aggressive application of the law of nature exception and maybe soften Alice's impact.  In Congress, a bipartisan group of legislators has been pushing for reform.  Senators Thom Tillis and Chris Coons, among others, recently re-introduced the Patent Eligibility Restoration Act (PERA) to rewrite § 101 and roll back some of the Alice-era exclusions.  But this is not the first time that a version of PERA has been introduced, and the patent community is waiting for the bill to get much closer to being a law before giving it their full attention.

    Thus, 2025 can be characterized as largely status quo in terms of patent eligibility.  Stakeholders are still watching the Supreme Court and Capitol Hill for rays of hope, perhaps a sense that someone, somewhere is going to pull the eligibility doctrine back to solid constitutional ground.  But there is no reason to believe that meaningful change will take place this year.

    Given this challenging landscape, what can attorneys, applicants, and patentees do to improve their odds of surviving a § 101 challenge?  While no strategy is foolproof (indeed, even the most meticulous drafting cannot guarantee eligibility under an uncertain test), there are techniques that can tip the scales at least a modest amount.  Patent practitioners over the last decade have essentially reverse-engineered the patterns of decisions to develop a playbook for software patents.  Below are some best practices as a mix of drafting tips and prosecution strategies to help prevent or overcome a § 101 challenge.

    1.  Focus on a specific technical improvement: Frame the invention as a solution to a technical problem, not a business.  Put differently, the claimed invention should improve the operation or performance of machines rather than that of businesses or people.  In the specification, clearly articulate the technological improvement or advantage the software provides.  For example, does it make a computer run faster, use memory more efficiently, use less network capacity, or operate under reduced power requirements?  Does it improve features fundamental and specific to computer technology, such as network security, data compression, parallel processing, or overall availability?  The Federal Circuit has emphasized that software claims directed to an improvement in computer functionality are not abstract.  Make sure the claims explicitly recite the features that form this improvement, and that the specification describes how those features solve a specific technical challenge.  In short, tell a story of innovation in real-world technology rather than casting the invention of an automation of a business process or human task.  In fact, try to avoid emphasizing or even mentioning any business process or human task at all.

    2.  Avoid outcome-driven claim language: Draft concrete, step-by-step claims that explain how the invention achieves its results.  Purely functional or result-oriented claims (e.g., "determining a classification for the data using machine learning") are red flags.  Instead, include the specific mechanisms or steps that carry out the improvement.  If your invention uses an algorithm, spell out key steps of that algorithm rather than claiming just the end result.  If it processes data, indicate how the data is processed in a new way.  Broad and generic claims are especially vulnerable under § 101, so consider adding technical limitations.  For instance, instead of "generating a network map," you might claim a specific step like "iteratively constructing a network map based on real-time telemetry data received from network nodes."  This helps tie the idea to concrete procedures or components.

    3.  Recite hardware or real-world effects (when possible): One way to show a claim is not abstract is to root it in a physical context or device.  If the software interacts with new or specialized hardware, include those details.  Even if it's running on a generic computer, mention any sensors, controllers, or other devices that are part of the system and used by the invention. Similarly, if the software produces a tangible real-world result (e.g., controlling an industrial process, adjusting a camera's settings, or providing a specific type of medical treatment), emphasize that.  Simply saying "by a computer" or "on the internet" is unlikely to help. But describing, for example, how a specific AI algorithm embedded in a medical imaging device yields clearer images for diagnosis will make the invention more concrete.

    4.  Highlight any non-conventional techniques: Under Alice step two (the inventive concept analysis), claims that merely use routine or well-known computer functions won't cut it.  If your invention uses an algorithm or data processing technique that is not conventional, or combines steps in a unique way, call that out in the specification.  The goal is to create a factual basis that, if someone later alleges that the claimed invention involves just standard computing, you can rebut that by pointing to your disclosure.  After the Federal Circuit's 2018 Berkheimer decision and ensuing USPTO memos, examiners are supposed to provide evidence when they claim something is well-understood, routine, or conventional.  While this policy is not always followed strictly, it arms you with an argument:  if you have described why your solution is innovative at a technical level, you can insist that an examiner (or court) acknowledge those concrete details rather than ignoring them.

    5.  Include a statement of technical improvement in the specification: In the unpredictable world of software patents, the specification is your lifeline.  Use it to explicitly teach why the invention is technologically significant.  Don't assume the benefit is obvious.  Include an explanation of the technical problem (e.g., "existing media distribution systems could not handle real-time network changes without significant adaptation delay, which led to failures in live streaming or broadcasting") and how your invention overcomes it ("the claimed embodiments provide a solution by incorporating an iterative machine learning model that dynamically updates a representation of the network in real-time, something not achievable with prior manual or static methods").  The statement of technical benefit can take various forms, but it should include descriptions of at least:  (i) the technical deficiencies in previous systems, (ii) the how the claimed invention overcomes these technical deficiencies, (iii) as many of the claimed invention's technical advantages as you can come up with (e.g., "by reducing the number of database accesses by an order of magnitude, these embodiments use less computational, network, and power capacity than conventional techniques.").  Finally, leave the door open for other technical improvements potentially flowing from the claimed invention as well as the possibility that this invention could be used to solve other technical problems not explicitly discussed in the specification.

    6.  Reinforce the technical improvement at every opportunity in the specification: Even a general statement of technical improvement might not be enough.  As you describe and specify the invention, consider enhancing each and every feature with a sentence or two describing its technical improvement.  The goal is to repeatedly hit the reader over the head with technical improvements, as well as to give you a number of locations in the specification to point to during prosecution or litigation that support the patent eligibility of the claims.  One example might be, "The system pre-allocates memory blocks in a deterministic schedule based on static task profiling, avoiding dynamic memory access during execution.  This eliminates runtime memory fragmentation and latency spikes in real-time systems, improving timing predictability and reliability and thus providing a concrete enhancement in computer memory management."  Another example might be, "The scheduler dynamically assigns processor cores and their clock rates based on predicted energy consumption models for application tasks derived from historical sensor and usage data.  Doing so reduces power consumption without user-perceivable performance degradation, directly improving hardware resource management in mobile computing."

    7.  Include performance results or data demonstrating an improvement: Benchmarking data, latency reductions, improved throughput, or lower resource usage can help substantiate that the invention provides a technical benefit.  However, applicants must exercise caution — if your claims recite an abstract idea, examiners and courts may construe performance gains as improvements to abstract idea itself rather than to the underlying computing technology.  To mitigate this risk, the specification should clearly tie the performance benefits to specific technical features — such as arrangements of software modules, hardware interactions, or architectural changes, rather than to general functional outcomes.

    8.  Add narrower embodiments that include more hardware or specific steps: In case the broad version of the claims hits an eligibility roadblock, these more focused embodiments might survive.  For example, reciting specific hardware components such as a sensor, display controller, or network interface can help anchor the claim in concrete technology rather than abstract functionality.  Similarly, adding detailed steps, like preprocessing data in a defined format, performing a particular type of signal transformation, or using a designated memory allocation strategy, can demonstrate that the invention is not merely a result-oriented abstraction.  These narrower embodiments provide fallback positions during prosecution or litigation and can help show that the claimed invention improves the operation of a particular machine or system.  In some cases, it may be beneficial to include at least one very narrow claim directed to the precise implementation over which protection is sought.  This forces the examiner to engage with a concrete technical contribution of the invention rather than dismissing all possible implementations as highly general abstract ideas.  Even if such a claim has limited commercial value on its own, it can serve as a foothold for establishing eligibility and opening dialogue during prosecution.

    9.  Be aware of USPTO examples and precedents: It can be helpful to draft claims that are comparable to ones that have been deemed eligible in the past.  The USPTO's examples (from 2019 and the 2024 update) provide model claims that the USPTO purports to be eligible.  If the invention is technologically similar to one of these examples, consider using language from the example in your specification.  Nonetheless, some examiners are skeptical of this USPTO guidance, as it does not have the authority of Federal Circuit case law.

    10.  Don't over-rely on Enfish and McRo: While these Federal Circuit cases are still good law and provide useful guidance for arguing that software-based claims can be eligible when they improve the functioning of a computer itself, they represent relatively rare wins in a legal landscape that has grown more skeptical of software patents.  Subsequent decisions have narrowed their reach, often distinguishing them on factual grounds or finding that later claims failed to recite comparable specificity.  Courts now expect a more rigorous showing that the invention solves a technological problem in a non-generic way, preferably with supporting disclosures in the specification that demonstrate how the claimed advance is achieved and why it matters from a technical perspective.  When drafting claims and a specification, do not assume that any similarities to the claims of Enfish or McRo will be given much weight by an examiner.

    11.  Always interview the examiner when you are dealing with a § 101 rejection during prosecution: Examiner interpretation of subject matter eligibility varies widely, and what one examiner considers a clearly abstract idea, another might view as a technological improvement.  These differences are often shaped by the examiner's background, personal approach to the Alice framework, and the prevailing norms of their art unit.  Different examiners and art units can have dramatically different § 101 rejection rates even within the same technical center.  An interview gives you the opportunity to understand how the examiner is construing the claims, what part of the specification they find compelling (if any), and whether they are open to particular claim amendments or additional details that could overcome the rejection.

    It bears repeating that even following all these best practices is not a guarantee.  The legal standard for patent eligibility remains, to put it mildly, a work in progress.  By heeding these lessons, however, particularly the careful tailoring of claims and the emphasis on detailed technical improvements in the specification, practitioners can significantly improve their chances of securing and defending software patents in this hostile environment.

    [1] https://www.patentdocs.org/2021/04/could-alice-be-used-to-invalidate-diehr-of-course-it-could.html.

    [2] https://www.patentdocs.org/2025/05/the-narrow-pathway-to-patent-eligibility-in-the-federal-circuit.html.

    [3] Numerous attorneys report anecdotally that the rate of § 101 rejections in 2025 has increased over that of previous years.

    [4] https://www.patentdocs.org/2024/08/91-that-is-the-rate-at-which-the-ptab-affirms-examiner-section-101-rejections.html.

    [5] https://www.patentdocs.org/2024/07/uspto-publishes-updated-subject-matter-eligibility-guidance-focusing-on-ai.html.

  • Treprostinil Saga Continues

    By Kevin E. Noonan —

    United Therapeutics Corp. (UTC) and Liquidia Technologies Inc. have been battling for close to a decade over their respective inhaled formulations of treprostinil (UTC's Tyvaso®, Liquidia's Yutrepia™) for treatment of pulmonary hypertension and their dispute is not yet over, both parties filing suits asserting patents against one another.

    Image 1Treprostinil

    In their extensive litigation, UTC has asserted claims in U.S. Patent No. 9,593,066 as well as U.S. Patent No. 10,716,793.  The District Court held that the asserted claims of the '066 patent were invalid for anticipation or were not infringed, a decision affirmed in all respects by the Federal Circuit, and that the asserted claims in the '793 patent were infringed and were not invalid (see "United Therapeutics Corp. v. Liquidia Technologies, Inc. (Fed. Cir. 2023)".  In an inter partes review proceeding, the Patent Trial and Appeal Board held that the challenged claims of the '793 patent (which the District Court held were infringed) were invalid for obviousness, a decision also affirmed by the Federal Circuit (see "United Therapeutics Corp. v. Liquidia Technologies, Inc. (Fed. Cir. 2024)).

    In the more recent cases, UTC asserted (in the Middle District of North Carolina, 1:25CV368, before Judge Thomas Schroeder, complaint filed on May 9, 2025) claims of U.S. Patent No. 11,357,782 (issued June 14, 2022, which expires May 14, 2027) for methods of treating pulmonary hypertension using dry powder formulations; claim 1 is representative:

    1.  A method of treating pulmonary hypertension comprising:
        providing an inhalation device for treating pulmonary hypertension in a human suffering from pulmonary hypertension comprising a powder formulation of treprostinil or a pharmaceutically acceptable salt thereof and a dry powder inhaler configured to administer single event dose of the powder formulation comprising treprostinil or a pharmaceutically acceptable salt thereof,
        wherein the single event dose comprises at least 15 micrograms to 90 micrograms of treprostinil or a pharmaceutically acceptable salt thereof delivered in 1 to 3 breaths,
        wherein the dry powder inhaler is configured to administer the entire single event dose in less than 5 minutes with at least 5 micrograms of treprostinil or a pharmaceutically acceptable salt thereof being inhaled per breath through coordinated actuation of the dry powder inhaler with each breath, and
        administering to a human suffering from pulmonary hypertension with the dry powder inhaler the single event dose comprising at least 15 micrograms to 90 micrograms of treprostinil or a pharmaceutically acceptable salt thereof in 1 to 3 breaths,
        wherein the human administers the entire single event dose with the dry powder inhaler in less than 5 minutes by inhaling at least 5 micrograms of treprostinil or a pharmaceutically acceptable salt thereof per breath by coordinating one actuation of the dry powder inhaler for each separate breath, and
        wherein administration of an additional single event dose in the same manner occurs at least 3 hours later.

    An important distinction is that UTC's product, encompassed by the limitations of the '782 patent is a new formulation of UTC's Tyvaso® product called Tyvaso DPI®, which obtained FDA approval in 2022 and (according to UTC's complaint) "is the first marketed dry powder formulation of treprostinil in the United States."  Liquidia's accused product, Yutrepiaä, is also a dry powder formulation of treprostinil approved by FDA on August 19, 2024.  However, this approval came with the caveat that Liquidia's product would not get final approval until UTC's 3-year regulatory exclusivity expired on May 23, 2025, which approval was granted when that deadline recently passed (although Liquidia has not yet put its Yutrepiaä product on the market).

    UTC alleges that practicing Yutrepia's label will literally infringe claim 1 of the '782 patent, as well as claims 2, 3, 8.  UTC's complaint, filed May 9, 2025 asks for a declaratory judgment of inducing infringement under 35 U.S.C. § 271(b) and contributory infringement under 35 U.S.C. § 271(c) based on Liquidia's current failure to launch their product.  UTC's allegations are based on "Liquidia's unauthorized development, manufacturing, commercial marketing, distribution, offers for sale, sales and/or use of Yutrepia™ (treprostinil) inhalation powder for the treatment of pulmonary hypertension ("PH")," based on "tentative approval" of Liquidia's Yutrepiaä product.  UTC's allegations are illustrated by this cartoon included in the complaint:

    Image 2
    Liquidia asserts non-infringement based on UTC's claims requiring coordination between actuation of the dry powder in the inhaler and inhalation by the patient, which is not required by the Yutrepia's device/method.  Liquidia further asserts invalidity based on the PTAB's invalidation of the '793 patent based on timing (the Final Written Decision of the IPR in the '793 patent was issued "only weeks after" allowance of the '782 patent), and that a related UTC application (US 2022-0323459 A1) was rejected for obviousness based on the reasoning in the FWD in the '793 IPR.

    In a separate litigation, UTC filed suit under the Hatch-Waxman Act in the District of Delaware against Liquidia's earlier Yutrepiaä product when Liquidia amended its NDA (NDA No. 213005, filed under § 505(b)(2)) for this drug to include a new indication, pulmonary hypertension associated with interstitial lung disease ("PH-ILD").  Initially UTC asserted the '793 patent (later invalidated by the PTAB in inter partes review; see above) and U.S. Patent No. 11,826,327, claim 1 being representative:

    1.  A method of improving exercise capacity in a patient having pulmonary hypertension associated with interstitial lung disease [i.e., PH-ILD], comprising administering by inhalation to the patient having pulmonary hypertension associated with interstitial lung disease an effective amount of at least 15 micrograms up to a maximum tolerated dose of treprostinil or a pharmaceutically acceptable salt thereof in a single administration event that comprises at least 6 micrograms per breath.

    Relevant to proceedings in the Middle District of North Carolina case (see below), UTC's motion for preliminary injunction to prevent Liquidia from marketing its Yutrepiaä product was denied in that case.  This case is set for trial this month.

    In another dispute in inter partes review, the PTAB invalidated UTC's challenged claims in U.S. Patent No. 9,604,901, with claim 1 being a representative claim:

    A pharmaceutical batch consisting of treprostinil or a salt thereof and impurities resulting from (a) alkylating a benzindene triol, (b) hydrolyzing the product of step (a) to form a solution comprising treprostinil, (c) contacting the solution comprising treprostinil from step (b) with a base to form a salt of treprostinil, (d) isolating the salt of treprostinil, and (e) optionally reacting the salt of treprostinil with an acid to form treprostinil, and wherein the pharmaceutical batch contains at least 2.9 g of treprostinil or its salt.

    This decision was affirmed by the Federal Circuit (see "United Therapeutics Corp. v. Liquidia Technologies Inc. (Fed. Cir. 2024)").

    For its part Liquidia sued UTC for infringement of its U.S. Patent No. 10,898,494, which patent issued January 26, 2021 and expires May 5, 2037 and recites representative claim 1:

    1.  A method for treating a patient, comprising:
        administration of a dry powder composition comprising
        from about 100 micrograms to about 300 micrograms treprostinil or a pharmaceutically acceptable salt thereof to a patient
        by inhalation using a dry powder inhaler over one to four breaths to treat pulmonary hypertension.

    Liquidia's complaint mirrors UTC's complaint but is limited to inducement and/or contributory infringement (the patient being the literal infringer by using the inhaler as prescribed).  Liquidia interprets UTC's treatment regimen containing on its label to direct patients to administer 112 micrograms (mcg) or 128 mcg at each treatment session for 4 sessions per day, which falls within the scope of UTC's asserted claims.

    The most recent activity in these litigations was the District Court's denial in its North Carolina action of UTC's motions for a temporary restraining order and preliminary injunction.  In denying these motions, the District Court held that UTC failed to satisfy the requirement for a showing of a likelihood of success on the merits and that Liquidia's Yutrepiaä product market entry would cause irreparable harm.  The basis for UTC's failure to satisfy the "likelihood of success" requirement focused on whether the asserted claims were invalid for obviousness.  As explained in the opinion, in the preliminary injunction context the burden on the accused infringer is to raise the invalidity issue "that [the patentee] cannot show 'lacks substantial merit,'" citing BlephEx, LLC v. Myco Indus., Inc., 24 F.4th 1391, 1399 (Fed. Cir. 2022).  But, the District Court cautioned, "[t]he burden of presenting a substantial question of invalidity at this stage is lower than what is required to prove invalidity at trial," under Entegris, Inc. v. Pall Corp., 490 F.3d 1340, 1351 (Fed. Cir. 2007), and other authority.  Here, Liquidia's basis for asserting invalidity was the PTAB's IPR decision that the '793 patent was invalid for obviousness (a decision that issued after the Examiner allowed the application leading to the '782 patent).  Liquidia's position is that the disparate decisions create a contradiction, insofar as the '793 invalidation was based on the same prior art as the '782 allowance (a representative claim from each patent shown side-by-side below):

    Table 1
    The Examiner for the application that resulted in the '782 patent reasoned that "a person of ordinary skill in the art would be unable to 'predict the dose, the number of breaths, and the timing of taking the drug' based on the relevant prior art," a conclusion not reached by the PTAB Board in invalidating the '793 patent (specifically the dose range, 15-90 micrograms, and delivery in "one to three" breaths).  Liquidia's invalidity argument was supported, they contended, by rejection of claims in UTC's U.S. Patent Application No. 17/745,333 for obviousness made after the PTAB's decision invalidating the '793 patent became available.  UTC's attempts to distinguish the limitations recited in these claims and the disclosure in the specification were unavailing in attempting to convince the District Court that Liquidia's obviousness arguments were unsupported by the evidence; the District Court supported its decision regarding such arguments by UTC's failure to convince the Examiner during prosecution of the '333 application using similar arguments, the comparison of the three sets of claims shown in this table:

    Table 2(It being clear that claim 1 of the '782 patent is recited with significantly more specificity (i.e., limitations) than the claims of either the '793 patent or the '333 application; nevertheless these distinctions were not persuasive before the District Court.)  And in the denial of UTC's preliminary injunction motion, Judge Schroeder rejected arguments based on any differences in effect regarding the '793 and '782 claims being method of treatment claims and the '333 application claims being directed to pharmaceutical compositions, saying that "[i]f it is not the case that what constitutes an obvious inference from the prior art with respect to a pharmaceutical product is obvious as to a method of treatment, UTC has not persuasively made that case."

    Turning to the "irreparable harm" prong of the requirements for a preliminary amendment, the District Court also found a lack of persuasiveness from UTC.  Rather, the Court was persuaded in part by UTC's delay in bringing suit on the '782 patent (from June 2022 until May 9, 2025, for purportedly strategic reasons, as well as a six-month delay from the date when FDA established Liquidia's Yutrepiaä product label — the Court characterized this situation as involving "last-minute filing").  Also relevant was Liquidia's assertion that it was sufficiently "financially viable" to compensate UTC for any monetary losses it might incur after a Yutrepiaä product launch.  The Court further expressed doubts about the risk of price erosion argued by UTC, and UTC's cause was not aided by statements by UTC executives minimizing the risk of a Yutrepiaä product launch, in some instances to be less than 5% of their current revenues.

    In view of UTC's failures in establishing the first two prongs of the requirements for being granted a preliminary injunction, the District Court's relatively perfunctory analysis of the other two prongs (balance of the hardships and the public interest) did nothing to change the outcome, and the Court denied the injunction of these grounds.

    As a consequence of the District Court's decision, within days Liquidia announced that it was preparing for a full commercial launch of its Yutrepiaä product.  And UTC's third quarter 2024 projected annual revenues of $3 billion provided important incentives for further litigation over this market.

  • Microprocessor v. Abacus: The Fictional Patent-Eligibility Debate between a Patent Attorney and a Retired Supreme Court Justice

    By Michael Borella —

    Background:  The oral argument of Bob v. Algorithm Savings & Loan (2014), p. 6:

    JUSTICE HÄAGEN-DAZS:  Imagine King Tut lounging outside his pyramid, surrounded by gold and bad financial instincts.  He's handing out chits left and right, "Good for one unit of gold, redeemable later."  He's got an abacus guy furiously moving beads to keep up.  Eventually, the abacus guy says, "Uh, dude, you've promised more gold than you actually have."  So Tut yells, "Stop!"  Crisis averted.  Or take my mother—she didn't need a computer.  Just one glance at my checkbook and she'd declare, "Hey, you've overdrawn. Stop!"  So now I ask you what, exactly, is less abstract about a computer saying "stop" instead of my mom or a Bronze Age accountant with a bead toy?

    Scene:  A quiet conference room at a law and technology symposium.  An experienced patent attorney with a degree in computer engineering sits across from retired U.S. Supreme Court Justice Häagen-Dazs.  They are discussing technology in the context of patent law.

    Justice Häagen-Dazs:  I've always been skeptical about software patents.  I recall, in Bob, we noted that using a computer to perform an abstract idea isn't enough.  After all, isn't a computer just a very fast abacus?

    Patent Attorney:  With respect, Justice Häagen-Dazs, I would argue that's a profound oversimplification.  An abacus is a passive mechanical tool.  It requires a human operator to interpret, manipulate, and extract meaning.  It doesn't process anything on its own.  A microprocessor, on the other hand, is an active, autonomous computing engine capable of executing millions of logic operations per second according to programmed instructions.  It doesn't just assist a person's calculation, it performs the calculation.

    Justice Häagen-Dazs:  But aren't both merely performing arithmetic?

    Patent Attorney:  The distinction lies in functional capacity and architecture.  A microprocessor implements a general-purpose model of computation, like a Turing machine.  It can simulate any algorithmic process, given enough time and memory.  In practice, an abacus has no such versatility.  It can't run an operating system, control a spacecraft, or manage a distributed database on its own or even with the assistance of a human.  It doesn't have conditional logic, memory registers, or instruction sets.  When patent law considers eligibility, this matters because we're not just talking about number crunching.  Computers are dynamic, programmable systems that change state and manage complex workflows.

    Justice Häagen-Dazs:  You mean my King Tut hypothetical from Bob was wrong?

    Patent Attorney:  Your analogies conflate what is being done with how it is being done.  Yes, the goal of preventing overspending is the same.  But the mechanism for achieving that goal in a computer is entirely different from a human using common sense or manually tallying numbers.  As a more tangible example, if the only known method of binding two pieces of wood together is a nail, then that should not prevent the inventor of the screw from obtaining a patent.

    Justice Häagen-Dazs:  But couldn't a human operating an abacus do anything a microprocessor could do?  Isn't it just a generic tool like a pen and paper or a handheld calculator?

    Patent Attorney:  No one has ever used an abacus to stream a video or encrypt HTTPS traffic, much less train a large language model — for good reason.  The analogy breaks down because an abacus can only be used to perform simple mathematical operations to solve small scale problems.  It would be absurd to contend that you could replace a modern graphical processor with even thousands of humans armed with abacuses.  The problems being solved and the solutions are fundamentally different.

    Justice Häagen-Dazs:  But the concern I had — and still have — is that merely implementing a longstanding human practice on a computer shouldn't suffice for patent eligibility.  Otherwise, we'd be monopolizing abstract ideas with trivial technological dressings.

    Patent Attorney:  The key question is whether the computer implementation is trivial.  If it merely automates a human practice using generic computing steps, such as storing, retrieving, and displaying, then forget about § 101 — it's not patentable as obvious.  But in many cases, the implementation is non-trivial in that the inventors aren't just using the computer as a faster pencil.  They are solving technical problems that arise only in the context of computer implementation.  Take for example a method of organizing human activity, say, a known manual accounting method.  If someone's claim is so broad that it covers that method, it's clearly unpatentable.  But if the same concept is implemented in a way that changes how the problem is solved because of the unique constraints or capabilities of the computing environment, and further the claim reflects this difference, then the computer is inseparable from this solution.  The notion of the abstract idea from Bob fails to reflect this fundamental fact.  Going back to a pre-Bob regime of patentability would not result in thousands of low-quality patents, especially if the USPTO properly applies the principles of obviousness, functional claiming, and definiteness from the patent statute.

    Justice Häagen-Dazs:  So in your view, the difference is not merely one of speed or convenience but of computational capability?

    Patent Attorney:  Precisely.  A microprocessor embodies a flexible, programmable platform capable of executing a vast range of machine-readable instructions.  It's not just an electronic abacus.  It is a fundamentally different class of tool.  Comparing it to an abacus is like comparing a steam engine to a horse.

    Justice Häagen-Dazs:  I see.  Perhaps I underestimated how much abstraction and logic can be embedded in hardware.  But I've been told over and over that there's something special happening under the hood in software patents, yet I can't see what's happening.  I'd rather err on the side of caution than risk giving twenty-year monopolies to ideas that should remain in the public domain.

    Patent Attorney:  Um, there's this thing called "discovery" where parties can produce evidence, such as source code, system architectures, and technical declarations from programmers, to show exactly what's happening "under the hood."  The courts don't have to guess.

    Justice Häagen-Dazs:  Yes, yes, I'm aware of discovery.  But even then, I see lines of code, flowcharts, declarations by experts with PhDs in computer science . . . and I still don't see a machine.  I see words.  Diagrams.  Assertions that something is "faster" or "more efficient."  To me, it's all just squiggly nonsense in a box labeled "processing unit."  It might as well be alchemy.

    Patent Attorney (getting visibly annoyed):  Justice Häagen-Dazs . . . Steve . . . a microprocessor is neither alchemy nor it is an abacus.  As my Gen Z kids like to tell me, this is what happens when you let old people make the important decisions . . . .

    Justice Häagen-Dazs (looking at a sundial strapped to his wrist):  Oh dear, is that the time?  I'm late for pickleball.  Toodles!

    Justice Häagen-Dazs stands up and hurries toward the exit, only to collide with an attendee entering the room.  The attendee's mobile phone (which happens to be running an investment app) slips from their hand and lands squarely on Justice Häagen-Dazs' foot.  He winces and curses the "abstract idea" that just fractured his toe and cost him six weeks of pickleball.

    End Scene