The recent case before the Hon'ble High Court of Madras concerning Section
3(i) of the Patent Act brought to light a crucial distinction between
"diagnosis" and "diagnostic." The case revolved around whether an invention that
involved testing nucleic acid molecules in a biological sample from a pregnant
woman to identify the fetal fraction could be considered diagnostic and
therefore barred under Section 3(i). This article provides an analytical
perspective on the case and the court's decision.
Section 3(i) of the Patent Act:
Section 3(i) of the Indian Patent Act is a significant provision that excludes
certain inventions from being patented. "It states that "a method of diagnosis
practiced on human beings or animals" is not patentable. The key issue in this
case was whether the invention, despite being related to diagnosis, was
inherently "diagnostic" in nature?"
The Rejected Patent Application:
The case arose from the rejection of an Indian patent application (No. 4812/CHENP/2012)
dated 01.06.2012. The application was denied on the grounds that it fell within
the scope of Section 3(i) of the Patents Act. The Assistant Controller contended
that the invention was essentially a diagnostic method, making it ineligible for
The Appellant's Argument:
The appellant argued that the invention did not diagnose a disease but rather
focused on identifying the fetal fraction in a biological sample. According to
the appellant, this identification was a critical step for subsequent diagnostic
testing. The argument revolved around the distinction between the identification
of the fetal fraction and the actual diagnosis of diseases, disorders, or
The court's decision was pivotal in this case. It allowed the appeal,
emphasizing that the invention involved testing nucleic acid molecules in a
biological sample to identify the fetal fraction. This fraction was crucial for
further testing to diagnose chromosomal aberrations. However, the court made a
critical distinction: the invention itself did not diagnose diseases, disorders,
or conditions. Instead, it provided an indicator (the fetal fraction) that was
relevant for subsequent diagnostic testing.
Defining "Diagnosis" and "Diagnostic":
The court delved into the meaning of "diagnosis" in the context of medical
science. It defined diagnosis as a method of identifying the existence or
non-existence of a disease or disorder and its various attributes. However, the
court noted that such identification, by itself, cannot be construed as a form
The term "diagnostic" in Section 3(i) was juxtaposed with words like "medicinal"
and "surgical," which are unquestionably forms of treatment. The court agreed
with the appellants that "diagnostic" should not be considered in isolation but
rather in conjunction with the accompanying words of Section 3(i) as a whole.
The court concluded that "diagnostic" should be limited to processes that reveal
pathology for the treatment of human beings.
Determining "Diagnostic" Processes:
The court provided guidance on how to determine whether a test is diagnostic. It
posed the question of whether the test is inherently and per se capable of
identifying a disease, disorder, or condition for treatment. This determination
should be made by assuming that persons skilled in the relevant field, including
medical professionals, examine the results. If these individuals would not be
able to diagnose the disease or condition based on the process because it is not
designed for that purpose, such a process, whether labeled as screening or
otherwise, should not qualify as diagnostic under Section 3(i).
Analyzing the Invention:
The court's analysis of the patent application revealed that the invention, as
described in claims 1 and 9, involved testing nucleic acid molecules in a
biological sample from a pregnant woman to identify the fetal fraction. Medical
literature indicated that a fetal fraction of not less than 4% was necessary for
further testing to identify chromosomal aberrations. Until this stage was
reached, pathology remained undisclosed, and treatment was not possible.
Therefore, the invention was inherently incapable of identifying the existence
or non-existence of a disease, disorder, or condition. The determination of the
fetal fraction related to diagnosis but was not inherently "diagnostic" in
The Concluding Note:
The case presented a complex and nuanced interpretation of Section 3(i) of the
Patent Act, highlighting the distinction between diagnosis and diagnostic. The
court's ruling clarified that a process should only be considered "diagnostic"
if it inherently identifies diseases or conditions, not if it merely provides a
step in a diagnostic process.
This decision has significant implications for patent law and the boundaries of
what can be patented in the field of medical diagnostics. It sets a precedent
for future cases where the distinction between diagnosis and diagnostic is in
question, emphasizing the importance of an inherent capability to identify
diseases or conditions for an invention to be barred under Section 3(i).
The Case Law Discussed:
Case Titled: The Chinese University of Hong Kong Knowledge Transfer office Vs
The Assistant Controller of Patent and Design
Date of Judgement/Order:12/10/2023
Case No. CMA (PT) No.14 of 2023 & CMP No.16669 of 2023
Neutral Citation No: 2023:MHC:4617
Name of Hon'ble Court: High Court of Madras at Chennai
Name of Hon'ble Judge: Senthil Kumar Ramamoorthy, H.J.
Information and discussion contained herein is being shared in the public
Interest. The same should not be treated as substitute for expert advice as it
is subject to my subjectivity and may contain human errors in perception,
interpretation and presentation of the fact and issue involved herein.
Written By: Advocate Ajay Amitabh Suman
, IP Adjutor - Patent and
Email: [email protected]
, Ph no: 9990389539