It is required that doctors should determine whether a particular dosage of a thiopurine drug is too high or too low for a particular patient with immune disorder. The claims of the patent involved in the case applied for the protection of the foresaid method used by doctors. It has been mentioned above that there are relationships between concentrations of certain metabolites in the blood and the likelihood that a dosage of a thiopurine drug will prove ineffective or cause harm and the claims of the patent involved in the case made a utilization of such laws of nature. Prometheus’ patents set forth laws of nature — namely, relationships between concentrations of certain metabolites in the blood and the likelihood that a dosage of a thiopurine drug will prove ineffective or cause harm. Claim 1, for example, states that if the levels of 6–TG in the blood of a patient who has taken a dose of a thiopurine drug exceed about 400 pmol per 8x108 red blood cells, then the administered dose is likely to produce toxic side effects. While it takes a human action (the administration of a thiopurine drug) to trigger a manifestation of this relation in a particular person, the relation itself exists in principle apart from any human action. The relation is a consequence of the ways in which thiopurine compounds are metabolized by the body — entirely natural processes. And so a patent that simply describes that relation sets forth a natural law. The question for further determination is whether the claims do significantly more than simply describe these natural relations. To put the matter more precisely, do the patent claims add enough to their statements of the correlations to allow the processes they describe to qualify as patenteligible processes that apply natural laws?
(i) The addition of new contents has been a common practice
If the laws of nature are unpatentable, then the method which cited the laws of nature can not be patented neither, unless the method has some other contents which can help to ensure that the method not merely tries to monopolize the law of nature itself by drawing support from patent drafting skills. The claim involved in the case contains an “administering” step, a “determining” step, and a “wherein” step. These additional steps themselves are not natural laws but neither are they sufficient to transform the nature of the claim.
First, the “administering” step simply refers to the relevant audience, namely doctors who treat patients with certain diseases with thiopurine drugs and patients with such diseases. That audience is a pre-existing audience and doctors had used thiopurine drugs to treat patients suffering from autoimmune disorders long before anyone asserted these claims. In any event, the “prohibition against patenting abstract ideas ‘cannot be circumvented by attempting to limit the use of the formula to a particular technological environment.’”
Second, the “wherein” step simply tells a doctor about the relevant natural laws, at most adding a suggestion that he should take those laws into account when treating his patient. That is to say, these steps tell the relevant audience about the laws while trusting them to use those laws appropriately where they are relevant to their decision making, which is very much like Einstein telling linear accelerator operators about his basic law and then hoping them to use it when necessary.
Third, the “determining” step tells the doctor to determine the concentrations of the relevant metabolites in the blood, through whatever process the doctor or the laboratory wishes to use. As the patents stated, methods for determining metabolite levels were well known in the art. Indeed, scientists routinely measured metabo l i t e s as part of t h e i r investigations into the relationships between metabolite levels and efficacy and toxicity of thiopurine compounds. Thus, this step tells doctors to engage in well-understood, routine, conventional activity previously engaged in by scientists who work in the field. Purely “conventional or obvious” “pre-solution activity” is normally not sufficient to transform an unpatentable law of nature into a patent-eligible application of such a law.
Last, to consider the three steps as an ordered combination adds nothing to the laws of nature that is not already present when the steps are considered separately. Such combination would no longer exist if these steps were examined individually. Anyone who wants to make use of these laws must first administer a thiopurine drug and measure the resulting metabolite concentrations of his patient, and so the combination amounts to nothing significantly more than an instruction to doctors to apply the applicable laws when treating their patients.
U.S. Court of Appeals for the Federal Circuit, in upholding the patent eligibility of the claims of the patent involved in the case, relied on the judgment rendered by U.S. Supreme Court in the past that “transformation and reduction of an article ‘to a different state or thing’ is the clue to the patentability of a process claim that does not include particular machines.” U.S. Court of Appeals for the Federal Circuit ruled that the claimed processes are eligible patent because they involve transforming the human body by administering a thiopurine drug and transforming the blood by analyzing it to determine metabolite levels.
The U.S. Supreme Court ruled as follows: The first of these transformations, however, is irrelevant. As we have pointed out, the “administering” step imply helps to pick out the group of individuals who are likely interested in applying the law of nature. And the second step could be satisfied without transforming the blood, should science develop a totally different system for determining metabolite levels that did not involve such a transformation. Regardless, in stating that the “machine-or-transformation” test is an “important and useful clue” to patentability, we have neither said nor implied that the test trumps the “law of nature” exclusion. That being so, the test fails here.
A conclusion can be drawn from the above analysis that the three steps stated by the claims involved in the case simply tell doctors to gather data from which they may draw an inference in light of the correlations. To put the matter more succinctly, the claims inform a relevant audience about certain laws of nature; any additional step consists of well-understood, routine, conventional activities already engaged in by the scientific community; and those steps, when viewed as a whole, add nothing significant beyond the sum of their parts taken separately. For these reasons, the steps are not sufficient to transform unpatentable natural correlations into patentable applications of those regularities.
(ii) The added contents are too broad
The laws of nature at issue here are narrow laws that may have limited applications, but the patent claims that embody them nonetheless implicate this concern. They tell a treating doctor to measure metabolite levels and to consider the resulting measurements in light of the statistical relationships they describe. In doing so, they tie up the doctor’s subsequent treatment decision whether that treatment does, or does not, change in light of the inference he has drawn using the correlations.
The “determining” step is set forth in too highly general language which covers all processes that make use of the correlations after measuring metabolites, including later discovered processes that measure metabolite levels in new ways. And they threaten to inhibit the development of more refined treatment recommendations that combine Prometheus’ correlations with later discovered features of metabolites, human physiology or individual patient characteristics.
As mentioned above, the steps included in the claims add nothing of significance to the natural laws themselves. That is to say, unlike atypical patent on a new drug or a new way of using an existing drug, the patent claims do not confine their reach to particular applications of those laws. The processes included in the patent claims are not eligible patent because they tie up too much future use of laws of nature.
IV. Exploration and Conclusion
American precedents require that patent should not be granted according to the interpretation based on the skills of patent drafter while turning blind eyes to those principles that patent shall not be granted to the laws of nature, and that no patent should be granted to method where the protection of its claims is so broad that it will monopolize the application of such laws of nature. For those method patents mainly relying on the use of the laws of nature, it is required to contain other elements or the combination of elements in order to ensure such method patent is not the laws of nature. The claims of the case of Mayo can not meet the above requirements. From a negative perspective, all other contents included in the claims are well-understood, routine, conventional activities previously engaged in by scientists in the field if the laws of nature are excluded from the operation steps. Meanwhile, if the court upholds such method to be granted a patent, the further application of such method would be limited, result in a risk of hampering the application of the laws of nature, and there would be a serious negative proportion between such risk and its promotion in scientific and technological advancement. From a positive perspective, all other contents would not transform claims into a practical and concrete application of the laws of nature after the exclusion of such laws from operation steps. Therefore, a comprehensive consideration will draw a conclusion that the claims involved in the case are unpatentable.
(Translated by Yuan Renhui)
