NewKerala.com

Delhi HC Upholds Patent Rejection for Nematode-Based Cancer Detection Method

The Delhi High Court has dismissed an appeal by Hirotsu Bio Science Inc., upholding the rejection of its patent for a cancer detection method using nematodes. The court ruled the invention constitutes a diagnostic process, which is non-patentable under Section 3(i) of India's Patents Act. It found the method involved all essential steps of diagnosis, including data analysis and drawing conclusions about disease presence. The judgment clarifies that the diagnostic exclusion applies regardless of whether the process is performed in vitro or by a medical practitioner.

Key Points: Delhi HC Rejects Patent for Nematode Cancer Test

  • Patent appeal dismissed
  • Method uses nematode smell for detection
  • Ruled a diagnostic process
  • Falls under Section 3(i) exclusion
3 min read

Delhi HC affirms patent rejection of Nematode-based cancer detection method as barred diagnostic process

Delhi High Court dismisses appeal, ruling nematode-based cancer detection is a non-patentable diagnostic process under Indian law.

"any process capable of identifying the presence or absence of a disease... would fall within the statutory exclusion - Delhi High Court"

New Delhi, January 19

The Delhi High Court has dismissed an appeal filed by Japan-based Hirotsu Bio Science Inc., upholding the rejection of its patent application for a nematode-based cancer detection method on the ground that it constitutes a non-patentable diagnostic process under Section 3 of the Patents Act, 1970.

In a judgment delivered on January 17, 2026, Justice Tejas Karia affirmed the order passed by the Assistant Controller of Patents and Designs, which had refused the grant of a patent for the invention titled "Cancer Detection Method Using Sense of Smell of Nematode".

The Court examined the complete specification and claims of the application and noted that the invention proposes detecting cancer by analysing the chemotactic response of nematodes to biological samples such as urine, cells, or tissues. The specification claimed exceptionally high accuracy, including detection of early-stage cancers, and described the invention as a "cancer diagnosis system."

Rejecting the appellant's argument that the invention merely involved in vitro detection rather than diagnosis, the Court held that Section 3(i) does not distinguish between in vivo and in vitro diagnostic methods. It observed that any process capable of identifying the presence or absence of a disease, even if further confirmation may follow, would fall within the statutory exclusion.

Hirotsu Bio Science Inc. contended that its method only indicated cancer risk and did not involve medical judgment or clinical decision-making. However, the Court found that the method involved all essential steps of a diagnostic process, including data collection, comparison with standard values, and drawing conclusions indicative of disease presence.

The Court further held that labelling the process as "screening" or "supporting documentation" could not override the substance of the invention, especially when the specification itself described the method as highly accurate and suitable for clinical cancer diagnosis.

The judgment emphasised that while claims define the scope of protection, they cannot be interpreted contrary to the complete specification. The Court relied on earlier precedents to hold that embodiments disclosed in the specification must be examined to determine whether the invention is per se diagnostic in nature.

It also rejected the argument that diagnostic exclusion should apply only to methods performed by medical practitioners, observing that the purpose of Section 3(i) is to prevent monopolisation of diagnostic processes irrespective of who performs them.

Upholding the Controller's decision dated August 29, 2023, the Court dismissed the appeal, concluding that the claimed invention clearly falls within the ambit of non-patentable diagnostic methods under Indian law.

- ANI

Share this article:

Reader Comments

R
Rohit P
Interesting case. Using worms to smell cancer sounds like sci-fi, but the legal principle is solid. Section 3(i) is clear. If the method tells you "you have cancer," it's a diagnosis, whether a doctor says it or a machine (or worm) does. Good call by the HC.
A
Aman W
While I understand the need to keep diagnostics accessible, this ruling might discourage innovation. If a foreign company develops a novel, low-cost detection method here, they won't get protection. We need to balance public interest with encouraging R&D investment in India.
S
Sarah B
The logic is sound. You can't just call it "screening" when your own patent says it's for "clinical cancer diagnosis." The court saw through the wordplay. This protects patients and keeps essential medical processes in the public domain.
K
Karthik V
As someone in biotech, this is a landmark interpretation of Section 3(i). The "in vitro vs in vivo" distinction is now clearly irrelevant for diagnostics. Companies will have to be very careful how they draft their specs and claims from now on. Kudos to the Indian patent office and judiciary.
M
Meera T
The principle is good, but I hope this doesn't mean we miss out on future tech. Cancer detection is so crucial for India. Maybe the law needs a review? Can we have a limited patent term for truly groundbreaking diagnostic methods to incentivize their development here? Just a thought.

We welcome thoughtful discussions from our readers. Please keep comments respectful and on-topic.

Leave a Comment

Minimum 50 characters 0/50