IP Cases & Articles

Myriad: Association for Molecular Pathology

On 29 July 2011, the Federal Circuit issued its much anticipated decision on the ‘Myriad case’. The court held that that claims directed to isolated DNA were patent eligible but diagnostic claims that relate to ‘comparing’ or ‘analysing’ sequences were patent ineligible.


Myriad Genetics is the owner or exclusive licensee of a series of patents claiming isolated DNA molecules (related to the genes known as BRCA1 and BRCA2) and methods for testing for the presence of mutations in these genes. Seven US patents had claims which sought protection for 1) isolated DNA containing all or portions of the BRCA1 and BRCA2 gene sequences, and 2) methods for “comparing” or “analysing” BRCA1 and BRCA2 gene sequences to identify the presence of mutations correlating with a predisposition to breast or ovarian cancer.

On 29 March 2010, the US District Court for the Southern District of New York issued a decision in which the claims at issue were declared invalid under 35 USC 101. Claims directed to DNA were held to be ‘products of nature’ while the method claims were held to fail the ‘machine or transformation test’.

The decision of the District Court was appealed and the Federal Circuit has now issued its opinion.

The Decision

Isolated DNA Composition Claims

The Court held that the Supreme Court’s decisions in Diamond v Chakrabartyand Funk Bros. Seed Co. v Kalo Inoculant Co. set out the framework for deciding patent eligibility of isolated DNA molecules and concluded that a distinction between a product of nature and a human-made invention for the purposes of 35 USC 101 turns on a change in the claimed composition’s identity compared with what exists in nature. Specifically, a distinction must be made between compositions that have similar characteristics as in nature and compositions that human intervention has given “markedly different” or “distinctive” characteristics. Applying this test to the isolated DNAs in this case, it was concluded that the challenged claims are drawn to patentable subject matter because the claims cover molecules that are markedly different — have a distinctive chemical identity — from molecules that exist in nature.

In reaching this decision, the Court considered that native DNA exists in the body as an integral part of a larger structural complex, a chromosome. In contrast, Myriad’s isolated DNA claims related to a free-standing portion of a native DNA molecule which has had covalent bonds in its backbone chemically severed. Human intervention in cleaving or synthesizing a portion of a native chromosomal DNA imparts on that isolated DNA a distinctive chemical identity from that possessed by native DNA.

The Court also rejected the plaintiff’s argument that isolated DNA is merely a product of nature because the isolated DNA shares its sequence with DNA in its native state in the chromosome. The Court held that this argument looks not at whether isolated DNAs are markedly different — have a distinctive characteristic — from naturally occurring DNAs but at one similarity, namely the information content contained in isolated and native DNAs' nucleotide sequence. It is the distinctive nature of DNA molecules as isolated compositions of matter that determines their patent eligibility rather than their physiological use or benefit. The Court held that the focus of this argument on uses is appropriate for deciding obviousness, not patent-eligibility.

Method claims

The Court upheld the District Court’s finding that the “comparing” or “analyzing” claims failed the machine-or-transformation test. Under this test: for a claim to be patentable, it must be 1) tied to a particular machine or apparatus, or 2) transform a particular article into a different state or thing. Applying this test, the Court found that the BRCA diagnostic claims do not specify any further action beyond the act of analyzing or comparing DNA sequences, and concluded that “analyzing” and “comparing” sequences are abstract mental processes.

Myriad argued that the claims should be read to contain transformative steps of (1) extracting DNA from a human sample, and (2) sequencing the BRCA DNA molecule, indicating that both steps necessarily precede the step of comparing nucleotide sequences. Not only were these steps not recited in the claims, the Court held that the specification required the term "sequence" to refer more broadly to the linear sequence of nucleotide bases of a DNA molecule.


The Decision insofar as it relates to the patenting of isolated DNA claims is in line with the USPTOs long standing practice that genes isolated from their natural environment may fall within the scope of patentable subject matter. While the Decision to affirm the District Court’s finding of patent ineligibility of certain diagnostic method claims is clearly of concern to those in the personalized medicine community, a petition for review by the US Supreme Court is widely expected.