Supreme Court Holds cDNA, But Not Isolated Genes, Patentable

June 14, 2013 – Blog Post

Supreme Court Holds cDNA, But Not Isolated Genes, Patentable

 A unanimous Supreme Court issued its decision yesterday in the closely-watched Myriad case, Association for Molecular Pathology v. Myriad Genetics, Inc., 569 U.S. __ (2013) (Thomas, J.).

Background of the Case

 Myriad originated in the District Court of the Southern District of New York when a coalition of groups and individuals brought a declaratory judgment action against Myriad Genetics, Inc. (“Myriad”) and other parties over several U.S. patents with claims based on the human breast cancer genes BRCA1 and BRCA2.  The patents include several types of claims, including claims to isolated DNA and cDNA[1] sequences and methods of using the sequences to identify mutations and possible cancer therapeutics.

 The District Court issued a lengthy decision declaring the patents invalid, emphasizing that isolating DNA “alters neither [the] fundamental quality of DNA as it exists in the body nor the information it encodes. Therefore [claims directed to isolated DNA] are deemed unpatentable under 35 U.S.C. § 101.”  The decision also found that the method claims based on comparing DNA sequences were unpatentable as abstract mental processes.

 The decision was appealed to the Federal Circuit and a three-judge panel reversed the district court’s decision, finding that claims covering isolated DNA and cDNA sequences are patent eligible.  653 F.3d 1329 (Fed. Cir. 2011).  The court held that because the isolated DNA molecules are chemically cleaved from native DNA, they have markedly different characteristics and therefore do not fall within the products of nature exception to 35 U.S.C. § 101.  The claims directed to methods of screening potential cancer therapeutics via changes in cell growth rates were also held to be valid.  Conversely, the court ruled all other method claims invalid, alleging these method claims are directed to abstract mental processes.

  The case was appealed to the Supreme Court, and while the petition for certiorari was pending, the Supreme Court issued its decision in Mayo Collaborative Services v. Prometheus Labs., Inc. (132 S. Ct. 1289, 101 U.S.P.Q.2d (BNA) 1961 (U.S. 2012)) (“Prometheus”), a decision squarely addressing patentability under 35 U.S.C. § 101.  In light of the Prometheus decision, the Supreme Court granted certiorari, vacated the Federal Circuit’s judgment, and remanded the case back to the Federal Circuit for further consideration in light of Prometheus.

 On remand, the Federal Circuit affirmed the District Court in part and reversed in part, with each member of the panel writing a separate opinion.  689 F.3d 1303 (Fed. Cir. 2012).  In short, two members of the court held that isolated DNA was patent eligible under 35 U.S.C. §101 (though disagreeing as to the rationale), and all three judges agreed that claims to cDNA are patent eligible.  The Court ruled all method claims were invalid as directed to abstract mental processes except for those directed to screening for novel cancer therapeutics.

 Summary of the Law

 Patent eligible subject matter is specified in 35 U.S.C. § 101, which states “whoever invents or discovers any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof, may obtain a patent…”  The Supreme Court has consistently construed 35 U.S.C. § 101 broadly.  However, there are three judicially created exceptions to patent-eligibility, including laws of nature, natural phenomena, and abstract ideas. 

 The USPTO, the Federal Circuit, and the Supreme Court have struggled with establishing clear standards for determining patent eligible subject matter.  In the recent Supreme Court case Bilski v. Kappos the widely-used “machine or transformation test” was held to be merely a clue, and not the sole test, for determining eligibility under 35 U.S.C. § 101. 130 S. Ct. 3218, 561 US __ (2010).  The Prometheus case provided some additional guidance for method claims, indicating that simply reciting well-known steps would be insufficient to transform the unpatentability of a natural law or abstract idea into patent eligible subject matter. 

 Yesterday’s Supreme Court Decision

 In granting certiorari, the Supreme Court agreed to hear only the question of whether or not human genes are patentable.  Furthermore, the Court also clearly limited its decision to isolated DNA and cDNA molecules encoding natural sequences, stating it does not consider “the patentability of DNA in which the order of the naturally occurring nucleotides has been altered.”
Thus, only claims directed to isolated DNA and cDNA were considered in the Court’s unanimous opinion. 

 The Court held that isolated DNA is not patent eligible, focusing on the invention as the actual sequence of the DNA rather than the specific chemical composition of a particular molecule.  Slip op. at 14-15.  This distinction is important because an isolated DNA molecule has cleaved bonds and is thus a chemically different moiety when compared to the naturally occurring DNA.  However, the sequence of the DNA and the genetic information contained therein are identical, and this persuaded the Court that isolated DNA is a non-patentable product of nature.   

 In contrast, the Court held that claims directed to cDNA are patent eligible, noting that “cDNA does not present the same obstacles to patentability as naturally occurring, isolated DNA segments.”  Since the non-coding portions of a gene sequence are missing in cDNA, “the lab technician unquestionably creates something new when cDNA is made.”


 The United States Patent and Trademark Office (“PTO”) immediately issued a Memorandum “to provide preliminary guidance to the Patent Examining Corps.”  The PTO instructs examiners to reject claims drawn solely to naturally occurring nucleic acids or fragments thereof whether isolated or not, and to consider method claims that involve naturally occurring nucleic acids for eligibility issues.  The PTO also notes that claims to non-naturally-occurring nucleic acids such as cDNA or variant sequences remain patentable.

 For applicants with cases pending at the PTO including claims to isolated DNA, it may be useful to file a supplemental amendment to ensure cDNA or variant claims are included.  Although not specifically mentioned by the Court or the PTO, tagged DNA molecules or other types of manipulated DNA are also likely patentable and should be considered.  Patentees with issued patents including isolated DNA sequences in the claims may choose to seek reissue of their patents to ensure adequate protection. 

 In addition, the Myriad case may have implications on patents and applications in other biotechnology areas based on isolated, naturally occurring products such as stem cells or proteins, and applicants/patentees should conscientiously consider their claims in light of the Myriad reasoning.  

[1] cDNA is a synthetic construct including only the coding portions of a gene.