Master The Supreme Court held that naturally occurring DNA segments are not patent eligible, but cDNA generally is. with this comprehensive case brief.
Association for Molecular Pathology v. Myriad Genetics is a landmark United States Supreme Court decision defining the contours of patent eligibility for genetic material under 35 U.S.C. § 101. The case sits at the intersection of science, innovation policy, and property rights, directly addressing whether human genes, once identified and isolated from the body, can be the subject of exclusive patent rights. In an era of rapidly advancing biotechnology and personalized medicine, the ruling clarifies how far innovators can go in claiming rights over the building blocks of nature while preserving access for research, diagnostics, and patient care.
The Court's unanimous decision—authored by Justice Thomas, with a brief concurrence by Justice Scalia—draws a critical line between discoveries of natural phenomena and human-made inventions. It reinforces the longstanding "product of nature" exception to patent eligibility while carving out a safe harbor for engineered genetic constructs like complementary DNA (cDNA). For law students, Myriad is essential to understanding Section 101 doctrine after Mayo and alongside Chakrabarty and Funk Brothers, and it illuminates the policy tensions between incentivizing innovation and maintaining open scientific commons.
569 U.S. 576 (2013)
Myriad Genetics, a biotechnology company, identified the precise location and sequence of the BRCA1 and BRCA2 genes on human chromosomes. Certain mutations in these genes sharply increase an individual's risk of developing breast and ovarian cancers. Myriad obtained several patents claiming: (1) "isolated" DNA molecules corresponding to the BRCA1/BRCA2 gene sequences; (2) cDNA (complementary DNA) molecules created in the laboratory that corresponded to the genes' coding regions (exons) without introns; and (3) certain methods of screening or analyzing DNA to detect mutations. The patents enabled Myriad to control the primary diagnostic testing market for BRCA-related mutations, affecting researchers and patients seeking access to testing and confirmatory analysis. A coalition of medical associations, geneticists, patients, and public-interest groups filed suit, challenging the validity of these claims under 35 U.S.C. § 101's patent-eligibility standard. The district court held the composition claims ineligible as products of nature. The Federal Circuit reversed in relevant part, concluding that isolated DNA and cDNA were patent eligible, although certain method claims were invalid. After the Supreme Court's decision in Mayo Collaborative Services v. Prometheus Laboratories (2012), the Court granted, vacated, and remanded; the Federal Circuit largely reaffirmed its view. The Supreme Court then granted certiorari limited to the patent eligibility of DNA claims and ultimately held that naturally occurring DNA segments are not patent eligible merely because they have been isolated, while cDNA—being synthetically created and not naturally occurring—is generally patent eligible.
Whether segments of human DNA that have been isolated from the genome, as well as cDNA synthesized from mRNA, are patent-eligible subject matter under 35 U.S.C. § 101, or whether they are unpatentable products of nature.
Under 35 U.S.C. § 101, laws of nature, natural phenomena, and abstract ideas are not patent eligible. A claimed composition that is a product of nature is ineligible unless it reflects a human-made invention with markedly different characteristics from any found in nature (Diamond v. Chakrabarty) and more than the mere discovery of a natural phenomenon (Funk Brothers). Merely isolating or discovering a natural product does not render it patent eligible, but a lab-created DNA construct that does not occur in nature—such as cDNA—may be eligible, provided it claims human-made invention rather than natural information.
Naturally occurring DNA segments are products of nature and are not patent eligible merely because they have been isolated. However, cDNA, which is synthetically created and lacks non-coding regions (introns), is generally patent eligible because it is not naturally occurring, except to the extent that very short cDNA sequences may be indistinguishable from naturally occurring DNA.
The Court emphasized that Myriad's principal contribution was locating and sequencing the BRCA1 and BRCA2 genes, not creating or altering the genetic information they contain. The claims to isolated DNA essentially covered the same genetic information found in nature; the act of cutting DNA from the chromosome and isolating it—despite breaking covalent bonds—did not create a composition with markedly different characteristics from the natural counterpart. The Court rejected Myriad's argument that chemical isolation alone conferred patent eligibility, focusing on the informational content and functional equivalence of the natural DNA and the claimed isolated DNA. In contrast, the Court found cDNA patent eligible because it is a synthetic, lab-created molecule that does not occur in nature. By reverse-transcribing mRNA, cDNA excludes introns, resulting in a man-made nucleotide sequence, which the Court deemed sufficiently distinct from naturally occurring DNA to qualify for patent eligibility. The Court cautioned that when a gene has no introns, cDNA may be indistinguishable from natural DNA and thus ineligible. Importantly, the Court limited its holding to composition claims and did not decide the patent eligibility of method claims or applications of knowledge about the BRCA genes, leaving room for patents on innovative applications and new techniques. Doctrinally, the decision harmonizes with Mayo's insistence that claims must add "something more" than a natural law or phenomenon, and with Chakrabarty's distinction between human-made inventions and products of nature. It preserves a core patent incentive for engineered constructs and tools while ensuring that mere discoveries of natural materials—even if difficult and valuable—remain in the public domain. Justice Scalia concurred in part, expressing some skepticism regarding the Court's recitation of complex molecular biology, but he agreed with the judgment and principal distinctions.
Myriad is pivotal for biotechnology and patent law: it forecloses exclusive rights over naturally occurring human genes, facilitating broader access to genetic testing and research, while preserving incentives to develop engineered DNA constructs like cDNA and innovative diagnostic methods. For practitioners and students, the case refines Section 101's product-of-nature doctrine, highlights the Court's focus on informational content and functional equivalence over formalistic chemical differences, and underscores careful claim drafting to emphasize human-made alterations or applications. It also illustrates the Court's incremental approach to patent eligibility after Mayo, leaving substantial questions about method and diagnostic claims to further litigation and legislative action.
No. The Court held that naturally occurring DNA segments are not patent eligible simply because they are isolated. But it expressly recognized that cDNA—a synthetically created DNA that excludes introns—is generally patent eligible. The Court also did not decide the eligibility of method claims or specific applications of genetic knowledge, which may remain patentable if they meet § 101 and the other statutory requirements.
Myriad argued that breaking covalent bonds to isolate DNA created a new molecule. The Court focused instead on the substance's informational content and functional properties, which remained the same as the DNA in nature. Mere isolation or purification, without a marked difference in characteristics, does not transform a product of nature into a patent-eligible invention under § 101.
Myriad applies Chakrabarty's principle that human-made inventions with markedly different characteristics from natural products are patent eligible, and it echoes Funk Brothers' prohibition on monopolizing natural phenomena. Natural DNA remains ineligible (like the mixed bacteria in Funk Brothers), but engineered cDNA is eligible (akin to Chakrabarty's genetically modified bacterium).
By invalidating patents on natural gene sequences, Myriad opened the door for multiple laboratories to offer BRCA testing and for researchers to study these genes without licensing constraints. This increased competition reduced costs and expanded access to confirmatory testing, while still allowing patents on engineered constructs and potentially on innovative diagnostic methods.
No. The Supreme Court evaluated only patent eligibility under § 101. It did not consider § 102 (novelty), § 103 (nonobviousness), or § 112 (disclosure) issues. Even where a claim is § 101-eligible (e.g., cDNA), it must still satisfy all other statutory requirements to be valid and enforceable.
The Court cautioned that very short cDNA sequences may be indistinguishable from naturally occurring DNA, especially when a gene lacks introns, and thus may not be patent eligible. Eligibility turns on whether the claimed composition is meaningfully different from what exists in nature.
Association for Molecular Pathology v. Myriad Genetics reaffirms that the patent system does not extend to discoveries of natural phenomena, even when those discoveries are difficult, valuable, and socially important. At the same time, it preserves patent protection for human-made inventions like cDNA, which reflect the kind of creative ingenuity that the patent laws aim to reward.
For law students, the case is a cornerstone of modern § 101 doctrine. It demonstrates how courts balance innovation incentives with the need to keep the basic tools of scientific and technological work free for all, and it underscores the importance of careful claim drafting to emphasize human ingenuity rather than the mere discovery of nature.
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