Non-Patentable Subject Matter in India: Sections 4 of the Patents Act

Continuing our Knowledge Base Patent Series, a practical guide for inventors, startups, and researchers to better understand patent protection in India.

For innovators, startups, and corporate R&D teams, understanding what can and cannot be patented in India is crucial. This section of the Indian Patents Act-Section 4 define key exclusions. This section applies for atomic energy inventions; such applications are referred to the Atomic Energy Regulatory Board for scrutiny after filing at Indian Patent Office. With the introduction of the SHANTI Act, 2025, the landscape for nuclear and other sensitive technologies has changed significantly, opening new opportunities for patent protection while safeguarding national interests.

Section 4:   Inventions relating to atomic energy not patentable.

No patent shall be granted in respect of an invention relating to atomic energy falling within sub-section (1) of section 20 of the Atomic Energy Act, 1962 (33 of 1962).

Historically, Section 4 prohibited patents for inventions related to atomic energy, as defined under the Atomic Energy Act, 1962. The goal was clear: maintain government control over strategic nuclear technologies and prevent misuse. While this ensured national security, it also blocked innovators from patenting inventions in peaceful applications such as nuclear medicine, radiation-based industrial solutions, and safety systems.

But now after the amendment in Section 4, SHANTI Act, 2025, has modernized this approach. Today, inventions related to nuclear energy with peaceful applications can be patented, while sensitive technologies that implicate national security remain under government control. This shift provides clarity and encourages investment and research in areas that were previously off-limits, creating a fertile environment for startups, multinationals, and research institutions to innovate responsibly.

Existing under the Patents Act continue to apply alongside the amended Section 4. Section 35 enables secrecy directions to be issued where an invention is considered relevant for defence purposes, restricting its publication or disclosure. Section 39 imposes restrictions on filing patent applications outside India without prior permission of the Central Government. These provisions operate in conjunction with the SHANTI Act to regulate the disclosure and protection of inventions relating to nuclear technologies.

Why this Section Matter?

Section 4 sets clear limits on what can and cannot be patented in India, especially when it comes to nuclear-related inventions. By understanding these limits, companies and researchers can make better decisions. They can focus their research and development efforts on inventions that are actually eligible for patent protection, avoid legal problems by ensuring their innovations meet ethical and technical requirements, and take advantage of new opportunities; particularly in peaceful nuclear and radiation-based technologies.

Importantly, the SHANTI Act has changed the earlier position under Section 4. Instead of completely banning patents for nuclear-related inventions, the law now allows patents for inventions meant for peaceful use, while keeping strict government control over technologies that may affect national security.

Today, India’s patent regime balances innovation, public interest, and national security. Nuclear and radiation-based inventions for peaceful purposes can now be patented, offering opportunities for commercialization, licensing, and global collaboration. Similarly, Section 5 ensures that only inventions with technical merit and social value receive protection, encouraging meaningful innovation across sectors.

For companies, startups, and researchers, this is an ideal time to explore patenting technologies that were previously excluded, secure legal protection, and participate in India’s growing innovation ecosystem with confidence.

𝐂𝐨𝐦𝐢𝐧𝐠 𝐍𝐞𝐱𝐭: Distinguish between Utility Patent vs. Design Patent