COMMENTARY: Laws of nature muddle patent certainty

After a long wait, the U.S. Supreme Court issued its opinionin Mayo v. Prometheus, an importantintellectual property case for the biotechnology industry. The court held thatthe correlation between blood test results and patient health is notpatentable, and that patents involving correlations with natural phenomena mustdo more than simply recite the natural correlation and then tell the user toapply it. Rather, correlation patents must confine themselves to particularapplications of these correlations applied in new ways, not simply usingwell-known steps.

The case mainly concerned the status of what has been themachine-or-transformation test when determining patent eligibility. Earlier, anappellate court characterized the central question as whether Prometheus'claims are drawn to a natural phenomenon, the patenting of which would entirelypreempt its use, or whether the claims are only drawn to a particularapplication of the phenomenon.

The patent in this case includes only two active steps,"administering" the drug and then "determining" metabolite levels. The claimexplains the correlation between metabolite levels and therapeutic efficacy and"what the inventors claim to have discovered is that particular concentrationsof 6-TG and 6-MMP correlate with therapeutic efficacy and toxicity in patientstaking AZA drugs."

The Supreme Court emphasized a concern over patents thatdisproportionately tie up the use of underlying natural laws, therebyinhibiting their use in the making of further discoveries, particularly infields not contemplated by the patentee. The court stated, "to transform anunpatentable law of nature into a patent-eligible application of such a law, apatent must do more than simply state the law of nature while adding the words'apply it.'" Further, the court stated, "the claimed processes are notpatentable unless they have additional features that provide practicalassurance that the processes are genuine application of those laws, rather thandrafting efforts designed to monopolize the correlations."

Justice Stephen Breyer delivered the opinion for a unanimouscourt, saying the relationships between concentrations of certain metabolitesin the blood and the likelihood that a thiopurine drug dosage will proveineffective or cause harm are not themselves patentable. Breyer noted that thethree additional steps in the claimed processes are not themselves naturallaws, but neither are they sufficient to transform the nature of the claims.

The court felt that the "administering" step simplyidentifies a group of people who will be interested in the correlations,namely, doctors who used thiopurine drugs to treat patients suffering fromautoimmune disorders. The "wherein" clauses simply tell a doctor about therelevant natural laws, adding, at most, a suggestion that they should considerthe test results when making their treatment decisions. The "determining" steptells a doctor to measure patients' metabolite levels, through whatever processthe doctor wishes to use.

Because methods for making such determinations were wellknown in the art, the court held that this step simply tells doctors to engagein well-understood, routine, conventional activity previously engaged in byscientists in the field. Such activity is normally not sufficient to transforman unpatentable law of nature into a patent-eligible application of such a law.Finally, considering the three steps as an ordered combination adds nothing tothe laws of nature that is not already present when the steps are consideredseparately.

The decision takes an already confusing area of law andmakes it more convoluted. The problem with the decision is that the conclusionfails to recognize that the administering and determining steps are part of atreatment protocol, and they are transformative. While the court did notaddress whether Prometheus' claims might be patent-eligible if the administeringand determining steps were less conventional, the decision could have asignificant impact on the fields of personalized medicine and medicaldiagnostics.

The question remains as to what happens if a claim recites aspecific manipulative step that is guided by a newly discovered natural law. Inthis case, the claims simply stated that when concentrations of a drug reachedcertain levels, it indicated a need to either increase or decrease thepatient's dosage. The claims could have recited affirmative steps such as"increasing the patient's dosage when the concentration is X" or similar steps.

This decision undermines another important policy in patentlaw, that of predictability. In the hopes of adding certainty andpredictability to patents involving correlations with natural phenomena, theSupreme Court surprisingly provided more unpredictability as to whether or nota particular claim would be patentable. Competitors need a predictable way todetermine the validity of a given patent, without having to resort tolitigation.

Stephen Jenei is a patent attorney at Jenei LLC,serving up chat at PatentBaristas.com