Summary
This analysis examines the Indian Patent Office’s refusal of Pfizer’s patent application concerning a known substance, highlighting an apparent contradiction with the Supreme Court’s Novartis decision. The post explores the interpretation of “known substance” under Section 3d, questioning whether unpublished patent applications can render a substance as “known”. The discussion also considers the implications of merging novelty analysis with subject matter assessment, as prohibited by the Supreme Court. The author argues that the decision raises significant concerns about the correct application of Indian patent law. The post adopts an objective, legal-academic approach to clarify these issues.
The Indian Patent Office’s refusal of a Pfizer patent application raises a question of interpretation that appears to sit uneasily with the principle established by the Supreme Court in the Novartis case. In the Novartis case, the Supreme Court clearly laid down that assessment of subject matter and novelty or inventive step cannot be merged, and that they are two separate elements of patentability analysis.
The Statutory Framework: Section 3(d)
Section 3(d) of the Patents Act reads as follows:
The mere discovery of a new form of a known substance which does not result in the enhancement of the known efficacy of that substance or the mere discovery of any new property or new use for a known substance or the mere use of a known process, machine or apparatus unless such process result in a new product or employs or least one new reactant.
The Explanation to Section 3(d) further states:
For the purposes of this clause, salts, esters, ethers, polymorphs, metabolites, pure form, particle size, isomers, mixtures of isomers, complexes, combinations and other derivatives of known substances shall be considered to be the same substance, unless they differ significantly in properties with regard to efficacy.
The Pfizer Application
In its patent application, Pfizer claimed the enantiomer of the known compound 3-{4-Methyl-3-[methyl-(7H-pyrrolo [2, 3-d] pyrimidin-4-yl)-amino]-piperidin-1- yl}-3-oxo-propionitrile. The compound claimed is an isomer of a compound in an earlier filed patent application, referred to in the order as D1, in which Pfizer is also an applicant. The patent application in question was filed before the base compound patent application D1 was published, meaning the base compound had not entered public knowledge at the time of filing.
The Novelty–Section 3(d) Question
The question arising is whether a compound disclosed in an unpublished document can be treated as a known substance for the purposes of Section 3(d). The Assistant Controller held that a prior filed but unpublished application in India is novelty-negating, and therefore acts as prior art for anticipation purposes, with the result that the substance is to be considered known. This reasoning raises a difficulty: it imports novelty analysis into the assessment of subject matter eligibility under Section 3, which is precisely what the Supreme Court in the Novartis decision cautioned against.
Scope of “Known Substance”
Even accepting, for the sake of argument, that the borrowing of novelty doctrine in this context does not amount to a merger of the two analyses — and is instead simply a tool for determining the meaning of prior knowledge in other patent contexts — a further question arises. If the doctrine of novelty is to be imported to interpret the scope of prior knowledge under Section 3(d), the same logic would seem to open the door to importing inventive step analysis as well. Whether such an extension would be countenanced is doubtful, but the Assistant Controller’s approach does not clearly foreclose it.
Technically, a compound known only to the applicant and forming the subject of an unpublished application is not part of public knowledge. On that view, Pfizer ought not to have been required to demonstrate enhanced efficacy relative to a compound that had not been published, since such a compound would not constitute a known substance in the ordinary sense of the term. The question of whether “known substance” in Section 3(d) extends to subject matter that is only within the private knowledge of the applicant remains unresolved by this order.
Disclaimer
This article is for general information and does not constitute legal advice. Readers should consult a qualified attorney before acting on any matter discussed here.