Intellectual Property Rights - Law and Practice · Indian Patent Law and its Developments

Convention Applications under Section 136 of the Patents Act

Updated 11 October 2026 · Fact-checked

A convention application is an Indian patent application based on a basic application first made in a convention country, filed within twelve months of it. Section 136 sets its conditions: a complete specification, the date and country of the first filing, and a statement of no earlier filing. Priority comes from section 135.

Understand Convention Applications under Section 136

Patent rights are national. A patent granted in one country gives no rights in another. But an inventor who files first abroad would lose novelty in India if the foreign application became public before the Indian filing. The convention system fixes this problem.

Under section 135, if you make a basic application in a convention country, you (or your legal representative or assignee) can file in India within twelve months of that date. For any claim based on matter disclosed in the basic application, the priority date is the date of the basic application. The Indian application filed under this route is called a convention application.

Section 136 lays down the special provisions for such an application. It must be accompanied by a complete specification. It must specify the date and the convention country of the application, or of the first of such applications. It must also state that no application for protection of the invention was made in a convention country before that date by the applicant or by anyone from whom the applicant derives title.

Section 136 also allows the complete specification to include claims for developments of, or additions to, the invention in the basic application. This is allowed only where the applicant would be entitled under section 6 to make a separate application for a patent for them, and subject to section 10. Those added claims do not get the foreign priority date. Priority attaches only to claims based on matter disclosed in the basic application. Other claims are dated under the other rules of section 11.

Finally, a convention application cannot be post-dated under section 17(1) to a date later than the date on which it could have been made under the Act. Related provisions: section 137 (multiple priorities), section 138 (documents, translations and the date proof) and section 8 (foreign filing information).

Key rules to remember

Time limit for a convention application: Indian application date ≤ date of basic application + 12 months; Section 135(1). If similar applications exist in two or more convention countries, count from the earliest one.
Priority date rule: Priority date of a claim = date of the basic application (only for claims based on matter disclosed in it); Section 135(1). Claims for new matter do not get that date.
Contents of a convention application (s.136(1)): (a) complete specification + (b) date and convention country of the first application + (c) statement of no earlier application in a convention country; All three are mandatory.
Developments and additions: Claims allowed, subject to section 10, if section 6 would entitle a separate application; Section 136(2). No foreign priority for the new matter.
Post-dating bar: Convention application cannot be post-dated under s.17(1) beyond the date it could have been made under the Act; Section 136(3).
Cognate inventions: One convention application for cognate or modified inventions, within 12 months of the earliest application; Section 135(2). Fee is as for separate applications for each invention.
Proof of the foreign date: Date = date the Controller accepts by certificate of the head of the foreign patent office or otherwise; Section 138(3). Under section 138(1) and (2), the Controller can call for copies of the foreign documents and English translations.

How to solve Convention Applications under Section 136 questions

Use this order for any problem or case question on convention applications.

1Identify the facts: where and when was the first (basic) application made, and who made it?
2Check the applicant: the person who made the basic application, or the legal representative or assignee.
3Check the time: is the Indian filing within twelve months of the earliest basic application? Count from the earliest if there are several.
4Check section 136(1): complete specification, date and country of first application, and the statement of no earlier application.
5Decide the priority date claim by claim. Matter disclosed in the basic application gets its date. Developments or additions do not.
6Note the compliance points: documents and translation on the Controller's request (s.138), foreign filing particulars (s.8), and the post-dating bar (s.136(3)).
7Write the conclusion: whether the filing qualifies and which priority date applies to which claim.

Quickest way: Three-check shortcut

When to use it: For short answers or when a case question has many dates.

Time: count twelve months from the earliest foreign filing.
Papers: complete specification, date and country, no-earlier-filing statement.
Content: priority only for matter already in the basic application.

Common mistakes in Convention Applications under Section 136

Treating the Indian filing date as the priority date for all claims.
Students forget that priority is claim-wise.
Fix: Apply section 135(1) claim by claim: only claims based on matter in the basic application take the foreign date.
Counting twelve months from the latest foreign application.
Students assume the most recent filing controls.
Fix: The Explanation to section 135(1) says to count from the earlier or earliest application.
Saying a provisional specification is enough for a convention application.
Confusion with the provisional route in section 11(2).
Fix: Section 136(1)(a) requires a complete specification.
Confusing section 135 with section 136.
They are read together.
Fix: Section 135 gives the right and the priority period. Section 136 lays down what the application must contain and related limits.
Equating a convention application with a PCT national phase application.
Both involve foreign filings and India.
Fix: A convention application is a direct Indian filing based on a basic application. A PCT international application designating India has the effect of an application under sections 7, 54 and 135, as the case may be, with the international filing date (s.138(4) and (5)).
Forgetting that section 8 particulars may be needed.
Students treat the foreign filing as irrelevant once priority is claimed.
Fix: Mention the applicant's duty to give detailed particulars of the foreign application and an undertaking to keep the Controller informed up to the date of grant.

Worked examples

Example 1

Aarav Technologies Pvt. Ltd., Pune, files a patent application for a battery management system in a convention country on 10 March 2026. On 20 February 2027 it files in India with a complete specification, specifying the date and country of the first application and stating that no earlier application was made in a convention country. The Indian specification also claims a new cooling module not disclosed in the foreign application. Advise on the priority dates.

Show the solution

Provision: section 135(1) gives priority from the basic application date if the Indian application is filed within twelve months. Section 136 sets the contents.
Time: twelve months from 10 March 2026 ends on 10 March 2027. Filing on 20 February 2027 is within time.
Contents: a complete specification is filed, and the date, country and no-earlier-application statement are given. Section 136(1) is satisfied.
Priority: claims based on matter disclosed in the basic application get 10 March 2026.
Cooling module: section 136(2) permits claims for developments or additions, subject to section 10 and if section 6 would entitle a separate application. But this matter is not in the basic application, so it does not get 10 March 2026. It is dated under the other rules of section 11, for example the date of filing the complete specification.

Answer: The application is a valid convention application. Claims on the battery management system have priority date 10 March 2026. The claim on the cooling module can be included but has no foreign priority; its priority date is determined under section 11, here the Indian filing date of 20 February 2027.

Example 2

Meera Pharma files basic applications for the same invention in country X on 5 January 2026 and in country Y on 20 April 2026. When is the last date to file a convention application in India for priority, and what priority date will apply?

Show the solution

Provision: the Explanation to section 135(1) says the twelve months run from the earlier or earliest application.
Earliest application: 5 January 2026 in country X.
Deadline: 5 January 2027.
Priority date: for claims based on matter in the basic application, the date of the basic application, which is the earliest disclosure here, 5 January 2026 (see also section 137 for multiple priorities).
Compliance: the application needs a complete specification, and the date and country of the first application must be specified under section 136(1)(b).

Answer: The last date is 5 January 2027, not 20 April 2027. Priority for the matter first disclosed in the country X application is 5 January 2026.

Exam tips

Write the provision first, then apply the dates to the facts, then conclude. Examiners reward this order.
Always show the twelve-month calculation with actual dates.
List the three contents of section 136(1) in a drafting or compliance answer.
If asked about difference from PCT, contrast a direct national filing based on a basic application with an international application designating India, and cite section 138(4) and (5).
Mention related sections briefly, 135, 137, 138 and 8, to show wider understanding.

Practice questions from Indian Patent Law and its Developments

Convention Applications under Section 136: frequently asked questions

What is a convention application under the Patents Act, 1970?

It is an Indian patent application made within twelve months of a basic application for the same invention in a convention country. It lets the Indian claims take the earlier foreign date as the priority date, for matter disclosed in the basic application.

What must a convention application contain under section 136?

It must be accompanied by a complete specification. It must specify the date and convention country of the first application. It must state that no earlier application for the invention was made in a convention country by the applicant or anyone from whom the applicant derives title.

What is the difference between a convention application and a PCT national phase application?

A convention application is filed directly in India based on a foreign basic application. A PCT international application designating India has the effect of an application under sections 7, 54 and 135, as the case may be, and takes the international filing date under section 138.

Can a convention application include new claims not in the foreign application?

Yes, claims on developments or additions can be included under section 136(2), subject to section 10 and the section 6 condition. They do not get the foreign priority date.