Under Indian patent law, various types of patent applications may be filed at the Indian Patent Office ("IPO"). This note discusses the different types of applications accepted at the IPO, and specific considerations relating to each type.

Provisional Patent Application

A provisional application is an interim patent application which is filed with a provisional specification. It is an optional application and need not be filed by every applicant. Every provisional application must be followed by a complete patent application in order to proceed for consideration by the IPO.

A provisional specification is expected to sufficiently cover the subject matter of the invention but need not contain all the sections or portions required in a regular patent application. It is usually filed when the invention has been developed, but experimental data or additional information to support the disclosure is still being collected. A provisional application helps establish a priority date for the invention and show that the applicant adequately possessed the invention at the date of filing of the application. It also gives the applicant sufficient time to evaluate the market potential of the disclosed invention before filing a complete specification. A provisional application need not include claims, and such applications are neither published nor examined.

A single provisional application can be the basis for filing more than one complete application so long as the provisional application includes support for each of those complete applications.

A complete patent application must be filed within 12 months of filing its corresponding provisional application. This timeline is not extendable under any circumstances. If an applicant does not file a non-provisional or complete application within 12 months, the provisional application is deemed to have been abandoned.

Complete Patent Application

A complete application is an application filed along with a complete specification describing the invention fully and particularly, including the best mode of working the invention. It can be filed directly or within 12 months of filing the provisional patent application. Complete patent applications can be of various kinds, depending on the priority sought, or the nature of the invention, as follows:

Depending on priority:

  • Convention patent application
  • PCT patent application
  • National Phase patent application

Depending on invention:

  • Divisional patent application
  • Application for a patent of addition

Convention Patent Application

A convention application is an application that claims a priority date based on the same or substantially similar applications filed in one or more "convention countries", i.e., parties to the Paris Convention for the Protection of Industrial Property. It must be filed within 12 months from the date of the first filing of a similar application in the convention country. For example, if an application for a patent is filed in the United States ("US"), a corresponding Indian convention application must be filed within 12 months of filing in the US.

The total number of applications filed in India claiming priority under the Paris Convention during the year 2018-2019 was 3,911 which was an 8% increase on the previous year figure of 3,644.1

PCT patent application

A PCT application is an application filed under the Patent Cooperation Treaty ("PCT"). It is first filed at one of the receiving offices under the treaty. The applicant may then file a "National Phase" application corresponding to the parent PCT application in any of the member states of the treaty within the prescribed time.

A PCT patent application effectively allows the applicant to postpone the expense of filing individual national patent applications in each of the countries where protection is sought. This also provides the applicant time to assess the value of the invention and analyse potential markets before making more significant investments in securing patent rights in multiple jurisdictions.

India is a member of the PCT. For a full list of the PCT members, please refer to https://www.wipo.int/pct/en/pct_contracting_states.html. PCT applications may be filed first in India, in relation to which National Phase patent applications may be filed in other member countries.

National Phase patent application

A National Phase application arises out of a PCT application. Such applications can be filed regardless of whether the parent PCT application has been published. A National Phase application in India must be filed within 31 months of the filing or priority date of the PCT application, whichever is earlier. This timeline is not extendable.

Most foreign applications in India are filed through the PCT National Phase route. The number of such applications filed in 2018-2019 was 26,966, which is a modest increase from the previous year's figure of 26,584.2

Divisional patent application

If the claims of a patent application relate to more than one invention, then the applicant may file a divisional application either suo moto or in response to an objection raised on the ground of plurality of distinct inventions in the claims by the IPO.

A divisional application can be filed any time before the grant of the parent application.

Applicants must be cautious that a patent may be granted or refused at any time after filing a response to the First Examination Report, Thus, if an applicant intends to file a divisional application, it should be filed as soon as possible. If a divisional application is voluntarily filed, during examination, the Examiner will assess whether or not the parent application relates to plurality of inventions.

The term of patent for a divisional application is the same as the term of the parent application, i.e., 20 years from the filing date or priority date of the parent application. Such applications are treated as substantive applications, and all the fees applicable to regular applications are payable in case of divisional applications as well.

Application for a patent of addition

An application for a patent of addition is made for an improvement or modification of an earlier invention for which the applicant has already applied for or has obtained a patent. It is granted only after the grant of the parent patent. However, if the parent patent is revoked, the patent of addition may be converted into an independent patent, upon the applicant's request.

An application for a patent of addition can be filed at any time after the filing of the parent application. It can even be filed after the grant of the parent patent and no separate renewal fee is required to be paid for a patent of addition. A patent of addition expires along with the parent application.

The examination of a patent of addition can only consider the main invention described in the complete specification of the parent patent or parent patent application for the purposes of assessing novelty but not for assessing the inventive step of a patent of addition.

Footnotes

1. https://ipindia.gov.in/writereaddata/Portal/Images/pdf/IP_India_Annual_Report_2019_Eng.pdf

2. https://ipindia.gov.in/writereaddata/Portal/Images/pdf/IP_India_Annual_Report_2019_Eng.pdf

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.