Pre-Grant and Post-Grant Patent Opposition in India

Patent opposition in India comes in two forms under Section 25 of the Patents Act, 1970. A pre-grant representation under Section 25(1) can be filed by any person once the application has been published and before a patent is granted. A post-grant notice of opposition under Section 25(2) can be filed only by a person interested, and only within one year from the date of publication of the grant. Both are decided by the Controller, both run on the same eleven statutory grounds, and both were reshaped by the Patents (Amendment) Rules, 2024.

The two are not alternatives you pick casually. They differ in who can file, what it costs, how fast the Controller must move, and what happens if you lose.

Pre-grant: Section 25(1)

Section 25(1) opens once the application is published and closes when the patent is granted. The words of the statute are wide: "any person may, in writing, represent by way of opposition to the Controller against the grant of patent". No standing needs to be shown, and the Controller must hear the opponent if a hearing is requested.

Rule 55 of the Patents Rules, 2003 supplies the machinery. The representation is filed in Form 7(A) at the appropriate office with a copy to the applicant, and must include the statement, the evidence relied on, and a request for hearing if one is wanted. Rule 55(1A) prevents any patent from being granted before six months have run from publication under Section 11A, which is the practical window in which a watch service is worth running. Rule 55(2) is the provision most people miss: the Controller shall consider the representation only when a request for examination has been filed. Filing against a dormant application achieves nothing until examination is requested.

Post-grant: Section 25(2)

Section 25(2) allows any person interested to give notice of opposition at any time after grant and before the expiry of one year from the date of publication of the grant. Note the trigger date. It is the publication of the grant, not the date the certificate reaches the patentee.

The notice is filed in Form 7 in duplicate under Rule 55A. Under Section 25(3)(b) the Controller must constitute an Opposition Board, which Rule 56 fixes at three members, and the examiner who handled the application during prosecution cannot sit on it. The Board examines the record and submits a reasoned joint recommendation on each ground. Under Section 25(4), after receiving that recommendation and hearing both sides, the Controller must order that the patent be maintained, amended or revoked.

Deadline warning. Two dates decide these cases. For the opponent, the one year from publication of grant under Section 25(2) is a hard outer limit. For the patentee, Rule 58 gives two months from receipt of the opponent's written statement and evidence to file a reply statement, and Rule 58(2) says that if the patentee does not contest or does not file in time, the patent shall be deemed to have been revoked. Patents have been lost on that sub-rule alone.

There are three ways to attack an Indian patent, and the calendar usually decides which one is open.

The eleven grounds are the same for both

Section 25(1) and Section 25(2) list clauses (a) to (k) in near identical terms, and each closes with the phrase "but on no other ground". In summary, they are wrongful obtaining, prior publication, prior claiming in an earlier filed Indian specification, prior public knowledge or public use in India, obviousness and lack of inventive step, that the subject matter is not an invention or is not patentable under the Act, insufficiency of description, failure to disclose information required by Section 8 or furnishing false information, a convention application filed beyond twelve months, non disclosure or wrong mention of the source or geographical origin of biological material, and anticipation by traditional knowledge available in any local or indigenous community in India or elsewhere.

Because the list is closed, an opposition drafted around commercial grievance rather than one of these clauses will not survive the maintainability stage. Two clauses do most of the work in Indian practice: the patentability objection under clause (f), which carries Section 3 exclusions including Section 3(d) and Section 3(k), and obviousness under clause (e). Section 8 non compliance under clause (h) is the sleeper ground, because it is documentary and does not depend on expert argument.

Pre-grant and post-grant patent opposition in India, compared

Physical filing is not permitted for either opposition fee entry, so both are e-filing routes. Fee figures are those in the First Schedule as substituted by the Patents (Amendment) Rules, 2024, and should be checked against the current schedule before filing.

What the 2024 Rules changed

The Patents (Amendment) Rules, 2024 made three changes that matter to opposition practice.

First, Rule 55(3) was replaced with a maintainability filter. The Controller now decides at the threshold whether a prima facie case is made out. If it is not, the opponent is notified, and unless a hearing is requested the Controller passes an order recording the grounds for refusal within one month. If a hearing is requested, the order follows within one month of the hearing. If a prima facie case is made out, the Controller passes a reasoned order within one month of receiving the representation and notifies the applicant. In practice this front loads the work: a thin pre-grant representation now dies early and with a written record against it.

Second, timelines tightened. The applicant's time to reply to a pre-grant representation under Rule 55(4) came down from three months to two, and the Opposition Board's time to submit its recommendation under Rule 56(4) came down from three months to two. The period for requesting examination under Rule 24B moved from forty eight months to thirty one months, which pulls the whole pre-grant window forward.

Third, Rule 138 now permits the Controller to extend time or condone delay by up to six months on a request in Form 4, made before that period expires, and it may be requested more than once within that six months. Rule 137 excludes certain provisions from the general power of amendment, including Rule 55(4).

Common mistake. Treating a pre-grant representation as a cheap way to delay a competitor. Since 2024 the Controller decides maintainability up front, the representation carries a fee, and a refused representation leaves a reasoned order on the file that the applicant will produce in every later proceeding. File on the merits or do not file.

How a post-grant opposition actually runs

1. Confirm the date of publication of grant and diarise the one year outer limit under Section 25(2). Confirm also that your client qualifies as a person interested.
2. File Form 7 in duplicate at the appropriate office under Rule 55A, with the prescribed fee.
3. File the written statement under Rule 57 along with the notice, setting out the nature of the opponent's interest, the facts relied on, the relief sought and the evidence, and deliver a copy to the patentee.
4. The Controller notifies the patentee under Section 25(3)(a) and constitutes a three member Opposition Board under Section 25(3)(b) and Rule 56.
5. The patentee files a reply statement and evidence within two months under Rule 58. Failure to contest or to file in time results in the patent being deemed revoked.
6. The opponent may file reply evidence within one month under Rule 59, strictly confined to matters in the patentee's evidence. Further evidence requires the Controller's leave under Rule 60.
7. The Opposition Board examines the material and submits a reasoned recommendation on each ground within two months of the documents being forwarded to it.
8. The Controller hears both sides and passes an order under Section 25(4) maintaining, amending or revoking the patent. Where the order is to maintain subject to amendment, the patent stands amended accordingly under Section 25(6).
9. An appeal lies to the High Court under Section 117A(2). Since the Tribunals Reforms Act, 2021 substituted "High Court" for "Appellate Board" with effect from 4 April 2021, there is no Intellectual Property Appellate Board to go to.

Four periods govern a contested post-grant opposition, and the second of them can end the patent by itself.

Strategy: which route, and when

Pre-grant is the cheaper and faster intervention and it is open to anyone, which matters when the real party in interest prefers not to be named. Its weakness is that it is decided by the same office that has been prosecuting the application, the evidentiary process is thin, and Section 117A(2) does not list Section 25(1) among appealable orders, so the fallback is writ jurisdiction rather than a statutory appeal.

Post-grant costs more and takes longer, but it produces a structured record, an independent Board recommendation, and a statutory appeal. It is also the route that can actually kill a granted patent at the office rather than in court. Where the client is already facing a threat of infringement proceedings, Section 64 revocation before the High Court, or a counter-claim in the infringement suit itself, may be the better place to fight, because validity and infringement are then decided together.

Key takeaway. The choice is usually driven by the calendar, not by preference. If the application is published, examined and not yet granted, Section 25(1) is available now. Once grant is published, you have twelve months for Section 25(2), and after that only Section 64 remains.

Indicative costs and timelines

Official fees are fixed by the First Schedule and set out in the table above. Professional fees are separate and vary widely with the technology, the volume of prior art and whether expert evidence is needed, so anyone quoting a single figure without seeing the specification is guessing. Searching and prior art analysis is often the largest line item in a serious opposition.

On timing, the rule based periods are the ones described above, but they describe the steps rather than the whole matter. In practice a contested pre-grant representation commonly runs several months to more than a year from filing to a speaking order, and a contested post-grant opposition frequently runs well beyond a year once hearings, adjournments and the Board's work are accounted for. Appeals add further time. Treat every number here as indicative and not as a commitment.

A note from practice

The oppositions that succeed tend to be narrow. Three well documented grounds pleaded precisely, with the prior art mapped claim element by claim element, do more than eleven grounds asserted at large. The second recurring point is Section 8: applicants with large international families sometimes file inconsistently, and that is a documentary ground which does not need an expert to explain. The third is timing discipline. Rule 58 is unforgiving of a patentee who misses two months, and Section 25(2) is unforgiving of an opponent who miscalculates the publication date of grant. For related reading, see our notes on patent registration in India, IP protection for startups and design registration in India, and our intellectual property law page.

Related guides and where to get help

If this is a live problem rather than background reading, our intellectual property practice handles these matters from Bengaluru, including for clients who cannot attend court in person. These guides go deeper on the neighbouring questions:

• Patent Registration in India: Process, Patentability and What to File
• Who Owns Copyright in AI-Generated Work in India?
• Passing Off Versus Trademark Infringement: The Practical Difference

Frequently Asked Questions

This article is general information on Indian patent law and is not legal advice. Fees, forms and timelines are as notified and should be verified against the current Rules before acting, and no outcome in any opposition can be predicted or promised.