Sections 16 explained: this guide covers what it means, who it applies to, the step-by-step process, documents required, fees, due dates and penalties in India — so you can stay compliant with confidence and avoid costly mistakes.
Sections 16 and 17 deal with two things the Controller can do to the date and shape of an application. Section 16 lets an applicant file a further application for an invention disclosed in the application already filed, either voluntarily or to cure an objection that the claims cover more than one invention. The further application is deemed filed on the date of the first. Section 17 lets the Controller post-date an application on request, by no more than six months, and deals with the date of an application amended on the Controller's requirement. If your first filing covered more than it should, patent drafting and filing choices about division start here.
Section 16: before grant, an applicant may file a further application for an invention disclosed in the provisional or complete specification already filed, either by choice or to remedy an objection that the claims relate to more than one invention. It needs a complete specification with nothing not in substance disclosed in the first one, and is deemed filed on the date of the first application. Section 17: the Controller may, on request before grant, post-date an application, but not later than six months from when it was actually made; and an application amended under section 15 may be deemed made on the date the requirement is complied with.
Section 16: the further application
Section 16(1): who may file, and when
A person who has made an application "may, at any time before the grant of the patent, if he so desires, or with a view to remedy the objection raised by the Controller on the ground that the claims of the complete specification relate to more than one invention, file a further application".
- Who: the person who made the first application.
- When: "at any time before the grant of the patent". The words "before the grant of the patent" were substituted in 2005 for earlier words about acceptance of the complete specification.
- Why: two reasons are named, joined by "or": "if he so desires", or "with a view to remedy the objection raised by the Controller on the ground that the claims of the complete specification relate to more than one invention".
- What: a "further application in respect of an invention disclosed in the provisional or complete specification already filed". The invention must have been disclosed in the first application's specification.
The heading speaks of "division of application", but the printed section uses the words "further application". Section 11(4) also refers to "a further application made by virtue of sub-section (1) of section 16". We use "divisional application" in headings as the common label, as in our post on divisional patent applications.
Section 16(2): the further application's specification
"The further application under sub-section (1) shall be accompanied by a complete specification, but such complete specification shall not include any matter not in substance disclosed in the complete specification filed in pursuance of the first mentioned application."
Two rules: a complete specification must go with the further application, and it must not add new matter that was not "in substance disclosed" in the first complete specification.
Section 16(3): no overlap
"The Controller may require such amendment of the complete specification filed in pursuance of either the original or the further application as may be necessary to ensure that neither of the said complete specifications includes a claim for any matter claimed in the other."
So each complete specification must claim different matter. The Controller may require amendment of either one.
The Explanation: deemed filing date and examination
"For the purposes of this Act, the further application and the complete specification accompanying it shall be deemed to have been filed on the date on which the first mentioned application had been filed, and the further application shall be proceeded with as a substantive application and be examined when the request for examination is filed within the prescribed period."
This Explanation was substituted in 2005. Two effects:
- The further application is deemed filed on the date of the first application. This ties in with section 11(4) (priority date from the specification where the matter was first disclosed) and section 11(7) (ante-dating under section 16).
- It is "proceeded with as a substantive application" and examined "when the request for examination is filed within the prescribed period". So a fresh request for examination is needed for it, within a prescribed period that the Act does not state; see section 11B.
Example. Solara Energy Pvt Ltd (fictional) files a complete specification claiming both a solar roof tile and a separate tile-mounting clip. The Controller objects that the claims relate to more than one invention. Under section 16(1), the company files a further application for the clip, accompanied by a complete specification that includes nothing not in substance disclosed in the first. The Controller may require amendments so that neither specification claims what the other claims. The further application is deemed filed on the first application's date, and it is examined once the company files the request for examination within the prescribed period.
Section 17: dating of an application
Section 17(1): post-dating on request
"Subject to the provisions of section 9, at any time after the filing of an application and before the grant of the patent under this Act, the Controller may, at the request of the applicant made in the prescribed manner, direct that the application shall be post-dated to such date as may be specified in the request, and proceed with the application accordingly:
Provided that no application shall be post-dated under this sub-section to a date later than six months from the date on which it was actually made or would, but for the provisions of this sub-section, be deemed to have been made."
Points:
- Who requests: the applicant, "in the prescribed manner" (which includes the prescribed fee).
- Who decides: the Controller "may" direct. It is discretionary.
- When: after filing and before grant.
- Limit: not later than six months from the date the application was actually made or would otherwise be deemed made. The six months is printed in the proviso.
- Subject to section 9. Section 9(4) has its own post-dating for an application with a provisional specification; section 17(1) is "subject to" it. See our article on section 9.
The words "before the grant of the patent" replaced earlier words about acceptance of the complete specification in 2005.
Why an applicant might ask. The Act does not say why. Post-dating moves the date, which affects later dates and priority treatment under section 11(7). We do not give reasons beyond what the text says.
Section 17(2): dating after amendment under section 15
This sub-section was substituted by the 2002 Amendment Act (with effect from 20-5-2003). Where an application, specification (including drawings) or other document is required to be amended under section 15 (see our article on section 15):
- if the Controller so directs, the application, specification or document is deemed made on the date the requirement is complied with; or
- where it was returned to the applicant, on the date it is refiled after compliance.
The words "if the Controller so directs" mean the re-dating is not automatic.
Summary table
| Provision | What it does | Who acts | Key limit |
|---|---|---|---|
| 16(1) | Further application for an invention disclosed in the first | Applicant | Before grant |
| 16(2) | Further application needs complete specification, no new matter | Applicant | "not in substance disclosed" |
| 16(3) | No claim overlap between the two | Controller may require amendment | Neither claims matter claimed in the other |
| 16 Explanation | Deemed filed on first application's date; examined on request | Applicant requests examination | Prescribed period |
| 17(1) | Post-dating on request | Controller, on applicant's request | Not later than six months |
| 17(2) | Re-dating after section 15 amendment | Controller may direct | On compliance or refiling |
What these sections do not say
- They name no fee, form or period for requesting examination of the further application.
- Section 16 does not limit the number of further applications, and section 17(1) does not say how the Controller decides whether to post-date.
Need help with ...?
Deciding whether to divide, and what to claim in each part, is easier before the Controller raises the objection. Our team can help you plan the structure of the filings under patent drafting and filing support.
Key takeaways
- A further application can be filed before grant, by choice or to remedy a "more than one invention" objection.
- Its complete specification must add nothing not in substance disclosed in the first.
- It is deemed filed on the date of the first application and is examined when a request for examination is filed within the prescribed period.
- The Controller may post-date an application on request, but not later than six months.
- An application amended under section 15 may be deemed made on the date of compliance, if the Controller so directs.
Read next
- Section 18 to 20: anticipation, potential infringement and substitution of applicants
- Section 11: priority dates of claims
- Section 15: power to refuse or require amendment
- Divisional patent application: when and how to file
Disclaimer: Based on the Patents Act, 1970 as amended up to the Jan Vishwas (Amendment of Provisions) Act, 2023, as consulted on 1 October 2026. Forms, fees and time limits under the Patents Rules, 2003 change from time to time and are not covered here. This article is general information, not legal advice; check the official text before acting.