Bioreactor Invention Involving Human Embryonic Stem Cells Not Patentable: Calcutta High Court

In a judgment dated January 16, 2026, a Single-Judge Bench of Justice Ravi Krishan Kapur, affirming the decision of the Deputy Controller of Patents, noted that inventions whose substance lies in biological material or parts of animals are excluded from patent protection under Section 3(j) of the Act.

The Court observed, “These aggregates are unequivocally parts of animals, and the invention though drafted in the form of a device or system, in effect seeks protection over animal or human biological material which cannot be patented.”

The patent application, filed by Viacyte Inc., sought protection for a bioreactor system used to culture primate pluripotent stem cell-derived aggregates in suspension using rotational culture techniques. The company claimed that the invention enabled efficient large-scale production of pluripotent cells by maintaining controlled growth and aggregate size.

The Patent Office rejected the application in May 2024 on multiple grounds including non-patentability under Section 3(j), lack of inventive step and lack of disclosure. It concluded that the bioreactor formats claimed in the invention such as stirred tanks, spinner flasks and rotating vessels were already known and commonly used for culturing mammalian and embryonic stem cells.

Viacyte challenged the rejection, arguing that the Patent Office had misunderstood the invention and that the claims related to a technical bioreactor system rather than to the biological material itself. It was submitted that the use of human embryonic stem cell-derived aggregates did not automatically render the invention non-patentable and that the claimed system involved technical advancement over prior art.

The Patent Office maintained that the claims were substantially directed towards biological material derived from animals and that the bioreactor merely served as a container with no technical advancement but use of routine cultivation techniques.

Agreeing with the Patent Office assessment, the Court held that, “One of the principal objects of the Patents Act, 1970 is to promote technological innovation in public interest while ensuring that patents are not granted for subject matters excluded from patentability or which do not comply with the requirements of novelty, inventive step or sufficient disclosure.”

It observed that Section 3(j) requires examination of the substance of the invention rather than its form and that routine changes over known parameters could not amount to an inventive step. It observed that suspension-based cultivation of pluripotent stem cells using known bioreactor systems was covered by the prior art and did not involve any technical advancement for grant of patent.

The Court also found that the application failed to disclose any novel feature in the bioreactor itself rather sought exclusivity over non-patentable biological material.

Consequently, the Court dismissed the appeal and upheld the refusal of the patent application.

For Appellant: Advocates Swati Mittal, Shika Singh and Abhirup Chakraborty

For Respondent: Advocates Rashmi Bothra and Priyanka Sarada