The laws of nature exclusion is one of the basic exceptions to patent eligibility in many jurisdictions. While the extent of its applicability may vary from country to country, it is recognized as one of the important elements for subject matter enquiry with respect to biology based inventions. Laws of nature include products of nature, natural relationships and natural phenomena, among others. The test that is commonly followed for determining whether an invention falls within the scope of laws of nature or not is the hand of man test. The test precludes anything that is obtained by human intervention from the scope of the exclusion.
Since its creation, the laws of nature exclusion is understood to cover anything that exists in nature but does not cover a practical application of the said law. The philosophy has been reiterated in the 2011 decision of the Supreme Court in the Mayo case. The case involved an invention based on the relationship between thiopurine drugs and metabolite levels in the body and claimed a process of determining the correct dose of the drugs based on levels of the metabolite. The Supreme Court held the claims to be non-patentable subject matter because the conventional methods followed in the processes do not amount to practical application of the natural relationship. It stated that the steps of administration of the drug, determination of metabolite levels and definition of the right dosage for a patient are all known and therefore, do not amount to practical application of the natural relationship between the drugs and the metabolite levels.
One inference that can be drawn from the decision of the Court is: Use of conventional methods to apply a natural relationship, would not make an invention patent eligible even if the natural relationship was not known earlier. To put it differently, if a series of steps form part of prior art, application of such steps to a natural relationship would not lend patent eligibility. Taking this logic a step further, the scope of laws of nature doctrine expands with the progress of state of the art, increase in size of prior art, and enhancement of predictability of the art.
The said conclusion has been affirmed by the Federal Circuit in the Myriad Genetics case with respect to a diagnostic process claim. The claim, which reads:
“1. A method for screening a tumor sample from a human subject for a somatic alteration in a BRCA1 gene in said tumor which comprises  comparing a first sequence selected from the group consisting of a BRCA1 gene from said tu-mor sample, BRCA1 RNA from said tumor sample and BRCA1 cDNA made from mRNA from said tumor sample with a second sequence selected from the group consisting of BRCA1 gene from a nontumor sample of said subject, BRCA1 RNA from said nontumor sample and BRCA1 cDNA made from mRNA from said nontumor sample, wherein a difference in the sequence of the BRCA1 gene, BRCA1 RNA or BRCA1 cDNA from said tumor sample from the sequence of the BRCA1 gene, BRCA1 RNA or BRCA1 cDNA from said nontumor sample indicates a somatic alteration in the BRCA1 gene in said tumor sample.” ( U.S. Patent 5,710,001)
The claim recites three steps to screen for breast cancer gene expression in somatic cells, first, a step of selecting the gene sequence from a tumor sample and non-tumor sample, comparing the gene sequences in the two samples and determining the existence of the tumor sequence in the non-tumor sample. The claim has been rejected patent eligibility because it involves mental steps and does not amount to practical application of a natural relationship between breast cancer susceptibility and presence of the gene sequence through use of conventional and well known methods. As the method of assessment formed part of the state of the art, the court concluded that its application to the natural relationship between the gene sequence and susceptibility to breast cancer would not be a practical application of the relationship.
The scope of laws of nature doctrine as it stands today, atleast in USA, involves assessment of state of the art. Practical application of a law of nature will be patent eligible only if atleast one of the steps or elements of an invention is novel. It is only logical to deduce from here that the scope of laws of nature exception is inversely proportional to state of the art and laws of nature analysis intrudes at some level into novelty analysis.
Authored by Dr. Kalyan