COVID-19 Underscores Diagnostic Patent Eligibility Problems

By Sharon Walker, Wanda French-Brown and Meghan Rachford
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Law360 (May 13, 2020, 4:14 PM EDT )
Sharon Walker
Wanda French-Brown
Meghan Rachford
The law of patent eligibility is in a state of chaos created through recent judicial precedent. A series of recent court opinions have held that, albeit novel, diagnostic methods related to discoveries about biological interactions and disease detection are not patent-eligible.[1]

The constitutional purpose behind patent law is to promote the progress of science.[2] For something to be patentable, it has to be new, nonobvious and useful, with the only exceptions being laws of nature, natural phenomena and abstract ideas. The U.S. Court of Appeals for the Federal Circuit's application of two U.S. Supreme Court decisions — Mayo Collaborative Services v. Prometheus Laboratories Inc. and Association for Molecular Pathology v. Myriad Genetics Inc. — has effectively broadened these exceptions therefore making it more difficult for some innovative life science companies to thrive.

The need for ongoing discovery of diagnostic methods has been highlighted by the recent outbreak of the COVID-19 pandemic — the very novelty of this disease will require innovation, particularly for new diagnostic methods that can be rapidly deployed to a large population. New diagnostic technology in this critical area may not be eligible for patent protection under the current legal landscape.

The Groundwork for the Current State of Affairs: The Mayo/Myriad Framework

The Mayo and Myriad decisions set the groundwork for recent cases holding that a series of diagnostic methods, while novel, are not patent-eligible.

Mayo established the two-part test that is now employed by the courts in assessing patent eligibility: (1) determine whether the patent is directed to a patent-ineligible concept, such as a law of nature or natural phenomenon, and, if so, (2) determine whether the claim limitations, when considered individually and as an ordered combination, transform the nature of the claim into patent‑eligible subject matter.[3]

In Mayo, the Supreme Court held that claims to a method of optimizing therapeutic efficacy were patent-ineligible. The claims included the steps of administering a drug to a patient with a particular disorder and determining the level of the drug metabolite in the blood.[4] In addition to reciting these steps, the claims recited metabolite concentration thresholds, above or below which indicates a need for the drug dose to be decreased or increased.[5]

In assessing patent-eligibility, first, the court held that the claims set forth laws of nature.[6] Next, it found that, individually, the administering and determining steps were well-known, that the "wherein" clauses tell a doctor about the relevant natural law, and that together, these limitations "amount[ed] to nothing significantly more than an instruction to doctors to apply the applicable laws when treating their patients."[7] Because of this, it held that the claims were not eligible to be patented.

In Myriad, the court found claims to isolated DNA sequences were not patent-eligible, as they claimed products of nature;[8] however, claims to man-made isolated cDNA were eligible and not products of nature.[9] Notably, the court implied that the outcome with respect to the isolated DNA may have been different in several circumstances.

The court gave three examples: (1) if an innovative method of manipulating genes had been developed, in contrast to the well-understood processes used to isolate the genes at issue; (2) if the patent covered new applications of knowledge related to the sequences; or (3) if the claims covered alterations to the naturally occurring genetic sequence.[10]

While both Mayo and Myriad struck down claims as ineligible, they note the importance of the patent system in encouraging innovation. The court made clear that there should be a "delicate balance between creating 'incentives that lead to creation, invention, and discovery' and 'imped[ing] the flow of information that might permit, indeed spur, invention.'"[11] ]

Despite this warning, the case law has led the industry down a trail that creates the risk that the Supreme Court hoped to avoid: the somewhat ambiguous test set out in Mayo has effectively led to a bright-line rule that any diagnostic method patent that does not involve a new technique to carry out that method is patent-ineligible.

The Federal Circuit in the Wake of Mayo and Myriad: Some Method Claims Are Patent-Eligible, But, for Diagnostics, Our Hands Are Tied

The Federal Circuit's interpretation of Mayo and Myriad is that there is a stark dichotomy when it comes to the eligibility of life sciences method patents: Methods of treatment and laboratory techniques are likely patent-eligible, but diagnostic methods relating to the same underlying technology likely are not. With diagnostics at the forefront of a new frontier in medicine, patent protection creates an incentive to create novel diagnostics for early disease detection and treatment.

Without early detection, the cost of medical care increases since patients require more care as treatment intensifies during late-stage disease progression. Although all Federal Circuit judges recently expressed significant discomfort with the current state of affairs, the Supreme Court has refused on many occasions to weigh in on this issue. This leaves it up to the Congress to fix the issue.

When it comes to diagnostic methods, the Federal Circuit has repeatedly held that such claims are patent-ineligible. Harkening back to Mayo, the Federal Circuit has interpreted that case as setting a relatively rigid rule that the application of conventional, well-known techniques to the discovery of a natural law or phenomenon in the diagnostic context does not transform the claims into patentable subject matter.

In 2015, for example, the Federal Circuit, in Ariosa Diagnostics Inc. v. Sequenom Inc., struck down patents for a blood test that revolutionized prenatal genetic testing by detecting and amplifying cell-free fetal DNA, or cffDNA, from a pregnant mother's blood.[12] The court noted that it was bound by precedent to hold that "valuable contributions to science" such as this are not patentable if they do not satisfy the Mayo test.[13] The patentee attempted to have the Supreme Court address the conundrum created by this decision, but the Supreme Court refused to review the case.[14]

This trend has continued into 2019 — the Federal Circuit has continued to strike down diagnostic method patents as covering ineligible natural laws or natural phenomena. For example, it struck down claims covering methods for detecting a naturally occurring heart disease marker, finding that well-known, standard techniques were used in the detection process.[15] And, in the context of veterinary medicine, it found ineligible claims covering genotyping dogs for a specific genetic nucleotide sequence for much the same reason.[16]

However, the Federal Circuit has reached the opposite result with other categories of method claims, specifically with respect to new laboratory methods, methods of treatment and, more recently, new preparation methods. All of these claims have been allowed to stand.

In Rapid Litigation Management Ltd. v. CellzDirect Inc., for example, the court upheld claims to a method of producing a preparation of hepatocytes by subjecting them to multiple freeze-thaw cycles as patent-eligible.[17] The court found that the claims were not directed to patent-ineligible concept, but to "a new and useful method of preserving hepatocyte cells."[18] Moreover, in the court's view, even if the claims encompassed a natural phenomenon (Mayo step one), they would pass Mayo step two because the claimed "process of repeating those [well-known] steps was itself far from routine and conventional."[19]

In Vanda Pharmaceuticals Inc. v. West-Ward Pharmaceuticals International Ltd., the court held that method of treatment claims invoking the natural relationship between a particular genotype and drug metabolism were patent-eligible because the claims were directed to applying a natural law — rather than the natural law itself.[20] Notably, the court pointed to the specificity of the claims at issue: "a specific method of treatment for specific patients using a specific compound at specific doses to achieve a specific outcome."[21]

These cases both indicate that specificity and new methods of implementing well-known steps may lend eligibility to patent claims, even if they relate to a natural law or phenomenon.

Most recently, in Illumina Inc. v. Ariosa Diagnostics Inc., the Federal Circuit held that preparation methods were patent-eligible. The Illumina case addresses a second string of patents that relate to the same core cffDNA technology that was struck down in Ariosa v. Sequenom Inc. in 2015.[22] Unlike the claims in the 2015 Ariosa case, which claimed detecting and amplifying cffDNA, in the recent Illumina case, the claims at issue included steps to separate the cffDNA based on its size.[23]

The Illumina court ultimately found that the claims were not directed to a natural phenomenon or law — step one of the Mayo test — because they included specific process steps that constituted "more than simply observing that fetal DNA is shorter than maternal DNA or detecting the presence of that phenomenon."[24] It is notable that the court made clear that this case is in a different factual category: "This is not a diagnostic case. And it is not a method of treatment case. It is a method of preparation case."[25]

The Supreme Court Refuses to Intervene

Whether diagnostic methods are patent eligible recently came to a head in the Athena Diagnostics Inc. v. Mayo Collaborative Services LLC en banc petition denial, in which every single Federal Circuit judge expressed dissatisfaction with the practical implications of its case law.[26] In that case, the court had found to be ineligible method claims related to the detection of naturally-occurring autoantibodies that bind to a specific protein — the discovery of a new cause of the debilitating autoimmune disorder, myasthenia gravis.[27]

Although the court credited the patentee with this discovery, it found that it was merely a natural law.[28] And, because the claim merely applied "standard techniques in a standard way" to detect the autoantibodies, the natural law was not transformed into eligible subject matter.[29]

When the patentee sought review en banc by the entire Federal Circuit, every single judge issued an opinion that indicated there is a problem when it comes to the patent-(in)eligibility of diagnostic methods.[30] As U.S. Circuit Judge Kimberly Moore aptly put it in describing the situation: "This is bad."[31]

Although the judges did not all agree as to the reason for the outcome, the majority indicated that they were bound to find ineligibility in this (and other) circumstances because of Mayo.[32] Several of the judges noted the need for patents to incentivize innovation, and many explicitly called on Congress and the Supreme Court to help them fix this problem.

The Supreme Court, however, again refused to get involved. On the same day, it denied a petition to review both the Athena case and the Vanda case, the case discussed above in which a method of treatment patent was found to be patent-eligible.[33] By refusing to take up two cases in the same industry that reached opposite results on the same fundamental legal question, the Supreme Court's message is clear: It is up to Congress to change things.

This effectively means that, unless Congress acts, the Federal Circuit finds ways to differentiate cases on the facts as it recently did in Illumina, or patentees modify their prosecution strategy, patents related to diagnostic methods may continue to fall.

Section 101's Uncertainty In Life Science: Possible Next Steps

All hope is not lost for diagnostic patents. As the industry continues to innovate in this area — providing life-saving technologies to patients — it must also consider ways to navigate the path set by the courts. This may be achieved by finding nuances in Federal Circuit holdings to uphold issued patents, modifying patent prosecution strategies to obtain new patents, and working with Congress to forge a clearer path in the future.

First, there is still a possibility that certain panels of Federal Circuit judges could hold that a specific diagnostic method claim is patent-eligible. While many Federal Circuit judges have stated that their hands are tied by Mayo, several of them — U.S. Circuit Judges Moore, Pauline Newman, Kathleen O'Malley, Evan Wallach and Kara Stoll — noted that Mayo can be differentiated under various factual circumstances.[34]

This has been borne out, for example, by the recent Illumina decision, where the court found claims passed Mayo step one (and covered patent-eligible subject matter) due to the specificity of the claimed processing method.[35] Even so, as Judge Moore noted, the court's "fervor for clarity and consistency has resulted in a per se rule that excludes all diagnostics from eligibility."[36] Indeed, in Illumina, the court noted at the forefront of its decision that the case was different because it did not involve a diagnostic method.[37]

Because the U.S. Patent and Trademark Office traditionally follows the rules set by the courts in examining patents, unless and until the law changes, patents must be drafted with an eye toward the confines of the current legal framework.[38]

One approach is to seek method of treatment claims that include, as claim limitations, the diagnostic techniques. As noted above, the courts have indicated that claims with more specificity, and which achieve a practical result, are more likely to stand. Another option is to emphasize — not only via the plain claim language but also in the specification — that diagnostic methods using well-known techniques are transformative because the techniques themselves are improved.

Companies should consider owning up to the fact that the diagnostic method relies upon well-known techniques and draft the claims in the Jepson improvement format, with the improvement being the specific application of these known techniques to the newly discovered diagnostic principle. This was suggested by U.S. Circuit Judge Alan Lourie in the 2015 Ariosa en banc decision.[39] No matter what approach is taken, it will be important to claim the diagnostic method with as much specificity as possible and to underscore this in the specification's overall description of the invention.

Finally, looking to the future, it is still possible that Congress will take action to alleviate the current state of Section 101 case law. This issue is currently under consideration by a group of politicians, who have put together a draft bill which appears to still be in the works.[40] When the draft bill was released, Rep. Stivers, R-Ohio, (one of the members of this task force) noted the importance of this issue for the life sciences industry and their patients:

[L]eaders in the fields of biologics research and diagnostics invest their time to discover lifesaving cures. ... [W]e must work to protect these innovators with the ability to secure a patent that rewards their risk and investment.[41]

The draft legislation would make several amendments to the Patent Act to reverse the outcomes that have occurred in the wake of Mayo and other precedent. First, it would amend Section 100 to define "useful" (a term that appears in Section 101 but is not otherwise defined) as "any invention or discovery that provides specific and practical utility in any field of technology through human intervention."[42] It would also amend Section 101 itself, deleting references to "new" and adding a new subsection requiring courts to only consider patent eligibility of the claim as a whole.[43]

The draft bill would also do away with the judicially created exceptions to eligibility — meaning that natural laws and natural phenomena would no longer be considered ineligible without some transformation or inventive concept, as has been required by the Supreme Court.[44]

Congress may not ultimately pass legislation that would explicitly undo the current problems with Section 101. It must balance the importance of incentivizing innovation to enhance healthcare with the concern that patent protection drives up healthcare costs. Until then, life sciences companies innovating in the field of diagnostics should find ways to differentiate their patents from those that have been struck down through creative patent prosecution strategies.

Without the incentive to innovate, it may not only be more difficult for life sciences companies to thrive, but the public will have limited access to new, cutting-edge diagnostic methods and related treatments. The ability to patent new diagnostic methods is currently in serious jeopardy, which has negative implications, not only for the life science industry, but for society at large.[45]

Based on the current law, patient care is at risk since diagnostic claims are off the table for patent protection. If innovating companies do not come up with new ways to diagnose various diseases, then patients and their families pay the price. Given the current COVID-19 pandemic, there is an urgent need for investment in innovation to create not only a vaccine but also new medical devices and diagnostic kits. Patent protection provides a strong incentive for companies to develop new diagnostics that may help to curb the devastating effects of this novel disease.



Sharon Walker, Ph.D., is a patent attorney at Translate Bio.

Wanda French-Brown is a partner and Meghan Rachford is an associate at McGuireWoods LLP.


The opinions expressed are those of the author(s) and do not necessarily reflect the views of Translate Bio, McGuireWoods, its clients, or Portfolio Media Inc., or any of its or their respective affiliates. This article is for general information purposes and is not intended to be and should not be taken as legal advice.

[1] Patent eligibility stems from the statutory requirement that an invention must have "utility" to be patentable. This requirement hails from the U.S. Constitution, which grants time-limited protection for inventions to "promote the progress of science and useful arts." See U.S. Constitution Article I, Section 8, Clause 8. Section 101 of the Patent Act, which governs utility, states, "any new or useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof" is eligible to be patented. See 35 U.S.C. § 101. Over time, the Courts have created "exceptions" to this rule, meaning that laws of nature, natural phenomena, and abstract ideas are not patent-eligible unless they are "transformed" by some "inventive concept."

[2] See U.S. Constitution Article I, Section 8, Clause 8.

[3] See Mayo Collaborative Servs. v. Prometheus Labs., Inc. , 566 U.S. 66, 77-80 (2012). Recently, this test has been applied in the context of abstract ideas, another category of subject matter excluded from eligibility. See Alice Corp. Pty. Ltd. v. CLS Bank Int'l , 573 U.S. 208, 217-18 (2014).

[4] Mayo, 566 U.S. at 74-75.

[5] Id.

[6] Id. at 77.

[7] Id. at 78-79.

[8] Ass'n for Molecular Pathology v. Myriad Genetics, Inc. , 569 U.S. 576, 580, 591 (2013).

[9] Id. at 580, 595. cDNA, as the Court explained, differs from DNA because it does not include non-coding regions that are present in naturally occurring DNA. Id. at 594-95.

[10] Id. at 595-96 (emphasis in original).

[11] Id. at 590 (quoting Mayo, 566 U.S. at 92).

[12] 788 F.3d 1371 (Fed. Cir. 2015), reh'g en banc denied, 809 F.3d 1282 (Fed. Cir. 2015).

[13] Id. at 1379-80 (quoting Myriad for the proposition that even "groundbreaking, innovative, or even brilliant discoveries" can be excluded from patent protection).

[14] See Sequenom, Inc. v. Ariosa Diagnostics, Inc. , 136 S. Ct. 2511 (2016).

[15] Cleveland Clinic Found. v. True Health Diagnostics , 760 F. App'x 1013, 1019 (Fed. Cir. 2019).

[16] Genetic Veterinary Scis. v. LABOKLIN , 933 F.3d 1302, 1318-19 (Fed. Cir. 2019).

[17] 827 F.3d 1042, 1048 (Fed. Cir. 2016).

[18] Id.

[19] See id. at 1051 (emphasis added).

[20] 887 F.3d 1117, 1136 (Fed. Circ. 2018).

[21] Id.

[22] See generally Illumina, Inc. v. Ariosa Diagnostics, Inc. , 952 F.3d 1367 (Fed. Cir. 2020); see also Ariosa Diagnostics, Inc. v. Sequenom, Inc. , 809 F.3d 1282, 1286 (Fed. Cir. 2015) (denying rehearing en banc).

[23] Illumina, 952 F.3d at 1369-70.

[24] Id. at 1373.

[25] See id. at 1371 (emphasis added).

[26] Athena Diagnostics, Inc. v. Mayo Collaborative Servs., LLC , 927 F.3d 1333, 1334 (Fed. Cir. 2019) ("Athena II") (denying rehearing en banc).

[27] Athena Diagnostics, Inc. v. Mayo Collaborative Servs., LLC, 915 F.3d 743 at 750-55 (Fed. Cir. 2019).

[28] Id. at 750-51.

[29] See id. at 753-55.

[30] See generally Athena II.

[31] See id. at 1358.

[32] See id. at 1334-52 (Lourie, Reyna, Chen, Hughes, Prost, Taranto, Dyk, JJ., concurring with denial of en banc review).

[33] See Athena Diagnostics, Inc. v. Mayo Collaborative, 140 S. Ct. 855 (2020). On the same day that it refused to take up review of Athena, it denied a similar petition in Vanda, the case in which a method of treatment patent was found to be eligible. See Hikma Pharms. v. Vanda Pharms. , 140 S. Ct. 911 (2020).

[34] See Athena II, 927 F.3d at 1352-73.

[35] See Illumina, 952 F.3d at 1371-74.

[36] Athena II, 927 F.3d at 1354 (emphasis added).

[37] See Illumina, 952 F.3d at 1371.

[38] The Patent & Trademark Office issued updated guidance to patent examiners on Section 101, including specific to the life sciences context, in October 2019. See https://www.uspto.gov/patent/laws-and-regulations/examination-policy/subject-matter-eligibility.

[39] Ariosa Diagnostics, Inc. v. Sequenom, Inc., 809 F.3d 1282, 1286 (Fed. Cir. 2015) (Lourie, J., concurring) (denying rehearing en banc).

[40] https://www.law360.com/articles/1243266?utm_source=ios-shared&utm_medium=ios&utm_campaign=ios-shared; https://www.tillis.senate.gov/2019/5/sens-tillis-and-coons-and-reps-collins-johnson-and-stivers-release-draft-bill-text-to-reform-section-101-of-the-patent-act.

[41] https://www.tillis.senate.gov/2019/5/sens-tillis-and-coons-and-reps-collins-johnson-and-stivers-release-draft-bill-text-to-reform-section-101-of-the-patent-act.

[42] Id.

[43] Id.; compare with 35 U.S.C. § 101 ("Whoever invents or discovers any new and usefulprocess, machine, manufacture, or composition of matter, or any new and useful improvement thereof, may obtain a patent therefor, subject to the conditions and requirements of this title." (emphases added)). Consistent with the proposed subsection (a), the draft bill also notes that "considerations relating to sections 102, 103, or 112" of the Patent Act have no place in the eligibility assessment. Id. ("Additional Legislative Provisions" section).

[44] See https://www.tillis.senate.gov/2019/5/sens-tillis-and-coons-and-reps-collins-johnson-and-stivers-release-draft-bill-text-to-reform-section-101-of-the-patent-act (stating, in "Additional Legislative Provisions," "The eligibility of a claimed invention under section 101 shall be determined without regard to: the manner in which the claimed invention was made; whether individual limitations of a claim are well known, conventional or routine; the state of the art at the time of the invention; or any other considerations relating to sections 102, 103, or 112 of this title.").

[45] See, e.g., Patent Eligibility Hearings, supra note 31 (statement of Judge Paul R. Michel (Ret.), U.S. Court of Appeals for the Federal Circuit), at 1, https://www.judiciary.senate.gov/download/michel-testimony (praising the Second Tillis-Coons Proposal as "a very good starting point [that] represents an enormous improvement over the present, intolerable chaos [in Section 101 law]"); Patent Eligibility Hearings, supra note 31 (statement of Q. Todd Dickinson, former Director of the PTO), at 36, https://www.judiciary.senate.gov/download/dickinson-testimony [hereinafter Dickinson Testimony] (expressing "general support for this positive proposal that should go far in clarifying and resolving several major issues . . . particularly the interpretation and use of § 101 . . . .").

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