The Core Rule: Novelty and What Destroys It
Patent law in India, as in most jurisdictions, requires that an invention be new at the time of filing. Any prior public disclosure of the invention, by the applicant or by anyone else, is treated as prior art that can destroy novelty and prevent grant. This is the default position.
Sections 29 to 34 of the Patents Act, 1970 create a narrow set of exceptions to this default. These are not a general grace period that protects all pre-filing disclosures. They are a closed list of specific circumstances in which a disclosure is excluded from the prior art assessment. If your disclosure falls within one of these circumstances, you have 12 months from the date of the disclosure to file your Indian patent application without losing novelty. If it falls outside these circumstances, the disclosure is treated as prior art regardless of when you file.
The Six Protected Circumstances
The following six circumstances are the only situations in which a pre-filing disclosure does not count as anticipation under Indian patent law. Each has specific conditions that must be satisfied.
| # | Type of Disclosure | Grace period |
| 1 | Unauthorised disclosure derived from the applicant A disclosure made by a third party without the applicant’s consent, where the information was derived from the applicant. The applicant must act promptly once the disclosure is discovered. The burden of establishing that the disclosure was unauthorised and derived from the applicant falls on the applicant. | Conditional |
| 2 | Communication to Government or authorised evaluators A disclosure made to the Government of India or to any person or authority authorised by the Government to assess the invention. This covers disclosures made in the context of regulatory review, government evaluation programmes, or specifically authorised bodies. | Qualifies |
| 3 | Display at an officially-notified exhibition Display or use of the invention at an industrial or other exhibition notified by the Central Government in the Official Gazette. The exhibition must be officially notified. A well-known trade fair or commercial expo that has not been officially notified by the Government does not qualify, regardless of its size or reputation. | Conditional |
| 4 | Description published because of an official exhibition A description of the invention published by any person in consequence of its display at an officially-notified exhibition. This covers publications that arise directly from the exhibition display. Independently published descriptions that merely reference the exhibition do not automatically qualify. | Conditional |
| 5 | Paper read before a recognised learned society A paper read before a learned society recognised by the Central Government, or published with the authority of such a society. The society must meet the statutory test of a ‘recognised learned society’. A professional conference, industry association, or academic workshop that has not been formally recognised does not qualify, regardless of academic reputation. | Conditional |
| 6 | Public working strictly for reasonable trial Use of the invention in public when the nature of the invention makes such public working reasonably necessary for technical trial or evaluation. This is narrowly construed. Public working for promotional, commercial, or market-testing purposes does not qualify. The public trial must be genuinely required because the technical assessment of the invention cannot be conducted otherwise. | Conditional |
What does not qualify
Any disclosure made outside these six circumstances is treated as prior art. This includes conference presentations at non-recognised societies, commercial product launches, publicly accessible websites, social media posts, press releases, pitch deck distributions, and investor demos. Even if you made the disclosure and even if it was accidental, it is prior art unless it falls within one of the six circumstances above.
Rule 29A and Form 31: The Procedural Requirement
The 12-month grace period under Sections 29 to 34 is not self-executing. Where a disclosure falls within one of the protected circumstances, the applicant must comply with two parallel procedural requirements within the same 12-month window.
The two deadlines that must both be met
First: the patent application must be filed within 12 months of the date of the qualifying disclosure.
Second: Form 31 must also be filed within that same 12-month period. Form 31 is the formal declaration of the qualifying disclosure, required under Rule 29A of the Patent Rules, 2003 (as amended 2024).
Both deadlines run from the date of the disclosure, not from any other reference point. A lapse in either deadline usually results in the disclosure being treated as prior art. Only in rare and exceptional circumstances is any scope for correction available.
The grace period begins on the date of the qualifying disclosure, not on the date you became aware of it, not when you personally delivered your presentation, and not when the event formally opened. Where multiple qualifying disclosures occurred on different dates, each date triggers its own 12-month clock.
Self-Assessment: Questions to Ask Before Relying on the Grace Period
Before treating a disclosure as protected, work through each of the following questions. Relying on the grace period when the disclosure does not actually qualify is not a neutral position. It may mislead you into delaying filing and losing novelty entirely.
| Was the exhibition officially notified by the Central Government in the Official Gazette? | If YES: Disclosure at that exhibition qualifies under Section 31. | If NO: The exhibition does not qualify, regardless of size or reputation. The disclosure is prior art. |
| Does the society that published or received your paper meet the statutory test of a ‘recognised learned society’? | If YES: Disclosure at that society or in its publications may qualify under Section 30. | If NO: The society does not qualify. The disclosure is prior art. |
| Was the public working genuinely required for technical evaluation of the invention, and impossible to complete without public access? | If YES: The public working may qualify as a reasonable trial under Section 32. | If NO: The public working was promotional, commercial, or capable of being done privately. It is prior art. |
| Has anyone uploaded, circulated, or published material about the invention outside the protected context after the qualifying event? | If YES: Each such publication may be a separate prior art event. Assess each independently. | If NO: No additional prior art events exist. The single qualifying event is the starting point. |
| Can you produce documents today to prove the disclosure qualified and when it occurred? | If YES: Your evidentiary position is sound. Maintain and preserve those records. | If NO: If challenged, you may be unable to rely on the grace period. Collect and preserve evidence immediately. |
What to Document: A Reference Table
To rely on the grace period, the applicant must be able to establish that the disclosure fell within one of the protected circumstances and when it occurred. The following table maps each disclosure type to the documents required.
| Disclosure Type | Documents to Preserve |
| Government communication | Written communication to the Government or authorised body; response or acknowledgement received; date of communication. |
| Officially-notified exhibition | Official Gazette notification; event registration or display confirmation; event programme; photographs of the display with date stamps; post-event publications if any. |
| Learned society paper or publication | Society’s Government recognition; invitation or acceptance letter; presentation programme with date and venue; published proceedings or journal issue. |
| Public trial or working | Technical justification for why public working was necessary; location and dates of public working; records of observations, test data, or evaluations conducted; confirmation that working was not promotional in character. |
| Unauthorised disclosure | Evidence identifying the third party who made the disclosure; evidence that the information was derived from the applicant; records showing when the applicant discovered the disclosure and what steps were taken immediately thereafter. |
| Post-filing disclosures | Copy of provisional or convention filing; evidence that the disclosed matter was already in that filing; dates of any subsequent public disclosures. |
Practical Guidance
1. Before any qualifying event
- Confirm whether the exhibition has been officially notified by checking the Official Gazette. Do not assume that a well-known event qualifies.
- Confirm whether the society meets the recognised learned society test before treating a presentation or publication as protected.
- File a provisional application before the qualifying event where possible. A prior provisional application gives you a priority date that predates the disclosure and removes the dependence on grace period protection.
2. Immediately after any qualifying event
- Set the 12-month deadline in your diary from the date of the disclosure, not from any other reference point.
- Create and preserve a contemporaneous evidence file: the Gazette notification, event programme, society credentials, presentation dates, and any publications arising from the event.
- Stop unprotected public disclosures immediately. Any additional disclosure outside the protected circumstances after the qualifying event is a separate prior art event.
- Inform all collaborators, co-inventors, and employees to avoid accidental uploads, social media posts, or presentations about the invention until the patent application is filed.
3. Before filing
- File both the patent application and Form 31 within 12 months of the qualifying disclosure. Both deadlines must be met. Filing the application without Form 31, or vice versa, does not preserve protection.
- If the disclosure was accidental, partly outside the protected categories, or involved a combination of protected and unprotected events, seek legal advice before relying on the grace period. The interaction between qualifying and non-qualifying disclosures requires case-specific assessment.
- Consider filing as early as possible in the 12-month window rather than waiting for the deadline. An earlier filing date strengthens the application against any intervening prior art.
Conclusion
Sections 29 to 34 of the Patents Act, 1970 create a closed and specific set of circumstances in which a pre-filing disclosure does not count as anticipation. When the disclosure falls within one of those circumstances, and when the applicant files both the patent application and Form 31 within the strict 12-month window, novelty is preserved. When the disclosure falls outside those boundaries, or when the procedural requirements are not met within the window, the disclosure is treated as prior art regardless of the applicant’s intent or awareness.
The practical lesson is the same in every case: file before you disclose where possible, confirm the status of any event before relying on it as a protected disclosure, and build a contemporaneous evidentiary record from the date of the first qualifying event.
Governing Law
Patents Act, 1970: Section 29, Section 30. Section 31, Section 32, Section 33, Section 34 | Patent Rules, 2003 (as amended 2024): Rule 29A | Form 31 (Declaration of Qualifying Disclosure)
