Section 35 of the Indian Patents Act: Secrecy Directions

“Innovation thrives when it is protected, but national security cannot be compromised”

In the world of patents, inventors typically know that publication of patent and examination are the part of the standard patent prosecution process. This transparency is the core of the patent bargain, whereby inventors disclose inventions in exchange for exclusive rights. But what happens when an invention could be of interest or falls under national security or defence purposes?

India’s patent law addresses this serious concern through Section 35 of the Indian Patents Act, 1970, which empowers the patent office to restrict or withhold the publication and disclosure of certain patent applications in the interest of the nation.

This blog walks you through the legal framework, procedure, real world examples, and practical implications associated with Section 35 of the Indian Patents Act in a way that’s both insightful and accessible.

Historical context and why this Exists

India introduced secrecy provisions to safeguard inventions that affect national security, adopting a philosophy similar to many other jurisdictions, as reflected in Section 35 of the Indian Patents Act, which empowers the Controller to impose secrecy directions where an invention is relevant to defence or security interests.

For example, in the United States, patent secrecy orders historically existed under 35 U.S.C. § 181 for inventions related to national defence.

The Indian framework reflects this need to ensure that strategically sensitive technologies are not disseminated prematurely, while still offering a mechanism to revert to public prosecution when risks abate.

Why secrecy directions matter

Section 35 exists because some inventions, though patentable, may pose risks if disclosed to the public. Patent publication normally occurs 18 months after filing; however, when technologies are sensitive for defence or security, premature disclosure could advantage foreign adversaries or jeopardize strategic capabilities.

Under Section 35, the Controller can issue secrecy directions to prevent publication, communication, and sometimes even examination, effectively placing the application in a confidential review loop.

Legal framework: Section 35 explained

Here’s how Section 35 works, sub section by sub section, with both legal context and practical interpretation:

Section 35(1): Controller’s authority to restrict publication

Under Section 35(1), the Controller of Patents can issue secrecy directions during preliminary review, if the Controller believes the invention:

• Is one of the classes of inventions notified by the Central Government as relevant to defence, OR
• Otherwise appears to be relevant to defence purposes

When these directions are issued, they can prohibit or restrict:

• Publication of the patent application, and
• Communication of any details about the invention
• Examination of the patent application during the period the secrecy directions remain in force.

This directive applies whether the application was filed before or after the Act’s commencement.

Example Scenario: Defence radar system

Suppose a team of engineers develops an advanced radar signal processing algorithm that enhances detection of low observable aerial threats. Although patentable, this technology could be strategically used by defence forces and equally misused if exposed. The Controller may invoke Section 35(1) to prohibit publication pending defence review.

Section 35(2): Government review of secrecy directions

Once the Controller issues secrecy directions, they must notify the Central Government, typically the Department of Defence or related authority. The Government then evaluates whether public disclosure would be “prejudicial to the defence of India.”

Two outcomes are possible:

• No prejudice found: The Government directs the Controller to revoke secrecy, allowing the normal application process to continue.
• Prejudice found: The secrecy direction stays in force. The application remains unpublished and confidentiality is enforced.

Example Scenario: Dual use secure communication protocol

A secure communication protocol developed originally for military networks later finds applications in civilian emergency response systems. Upon review, the Government might determine that public disclosure no longer threatens defence interests, and revoke the secrecy directions.

Section 35(3): Government initiated secrecy directions

Section 35(3) close the loop by enabling the Central Government to independently notify the Controller that an invention is defence relevant, even if the Controller has not initially issued secrecy directions.

This can happen at any time before the grant of a patent, and once notified, the Controller must apply Section 35(1) procedures as if the invention were already classed as defence relevant.

Example Scenario – Government Intervention

Consider a civil aviation navigation algorithm with unexpected military utility. The Controller may overlook its defence value initially, but upon Government review, secrecy directions can be imposed under Section 35(3) to protect strategic interests.

Secrecy directions in practice: What happens to the application?

Once secrecy directions are in place:

• Publication is halted: The standard 18-month publication does not occur.
• Communication is restricted: Applicants cannot publicly disclose details.
• Examination may be deferred or restricted: While the examiner may continue evaluating patentability, public prosecution steps are suspended.
• Foreign filing and disclosure controls apply: Related filings overseas require careful compliance and, in some cases, prior government approval.

At this stage, inventors often worry: Will my patent be rejected or lost because of secrecy?

This is exactly where Section 37 becomes important.

Section 37: Protection for inventors during secrecy

Section 37 ensures that secrecy directions do not harm the inventor’s patent rights.

While secrecy is in force:

• The controller cannot refuse the application
• The application and specification remain confidential
• No appeal lies against the secrecy order during this period

Section 37 keeps the application in legal suspension, not rejection.

The patent process is paused not terminated. Once secrecy is lifted, the application picks up from where it stopped.

Practical implications for inventors and businesses

Section 35 affects strategy, timing, and compliance. Two considerations are particularly important:

1. Patent strategy and business planning

In high tech domains such as aerospace, encryption, or defence systems, inventors should anticipate that their inventions might be subject to scrutiny under Section 35. It’s essential to factor this into:

• Filing timelines
• Commercial disclosure plans
• Foreign filing strategy

Failure to plan in advance can lead to unintended publication bans or delays. 

2. Legal compliance and penalties

Non-compliance with secrecy directions can lead to serious consequences. For instance, under Section 40, contravening the Controller’s secrecy direction or filing abroad without permission under Section 39 may result in:

• Abandonment of the Indian application
• Revocation of patent rights
• Penalties including fines or imprisonment under Section 118 of the Act

This underscores why inventors must strictly abide by the restrictions once a secrecy directive is issued.

Conclusion

Section 35 of the Indian Patents Act serves a very specific but crucial function: protecting national security interests without extinguishing inventors’ intellectual property rights. By empowering the Controller and the Central Government to issue and review secrecy directions, the law creates a balance between technological transparency and strategic confidentiality.

For inventors, business owners, and IP stakeholders working in advanced technological domains, understanding Section 35 is not optional it is essential for compliance, strategic patent planning, and risk management in India’s patent ecosystem.