How to File a Pre-Grant or Post-Grant Patent Opposition Under the Patents Act 1970 in India

The Indian patent system provides a robust mechanism for challenging the validity of patent applications and granted patents through opposition proceedings under Section 25 of the Patents Act, 1970. These proceedings serve as a crucial check against the grant of patents that do not meet the statutory requirements of novelty, inventive step, and industrial applicability. The law provides for two distinct types of opposition: pre-grant opposition under Section 25(1), which can be filed by any person before the patent is granted, and post-grant opposition under Section 25(2), which can be filed by any person interested within one year of the publication of the grant. This guide covers the complete procedure for filing both types of patent opposition in India, including the applicable forms, fees, grounds, evidence requirements, the role of the Opposition Board, and key changes introduced by the Patent (Amendment) Rules, 2024. For related IP protection strategies, see our guide on opposing a trademark application before the Registrar.

Understanding Patent Opposition Under Section 25

Section 25 of the Patents Act, 1970 is the primary statutory provision governing patent opposition in India. It was significantly amended by the Patents (Amendment) Act, 2005, which introduced the current framework of pre-grant and post-grant opposition. The purpose of these provisions is to allow third parties to challenge patent applications or granted patents on specific statutory grounds, thereby ensuring that only genuinely novel and inventive inventions receive patent protection. The opposition mechanism serves as an alternative to costly and time-consuming patent revocation proceedings under Section 64 of the Act.

Pre-Grant Opposition Under Section 25(1)

Pre-grant opposition under Section 25(1) can be filed by any person after the patent application has been published under Section 11A but before the patent is granted. The term 'any person' is interpreted broadly, meaning that there is no requirement for the opponent to demonstrate a personal or commercial interest in the matter. This makes pre-grant opposition a powerful tool for public interest challenges, including those against patents on essential medicines or traditional knowledge. The opposition is filed by way of a representation to the Controller of Patents in Form 7A, along with a statement and supporting evidence. The Controller first examines the maintainability of the representation before issuing notice to the patent applicant.

Post-Grant Opposition Under Section 25(2)

Post-grant opposition under Section 25(2) can be filed by any person interested after the grant of a patent but before the expiry of one year from the date of publication of the grant. Unlike pre-grant opposition, the opponent must be a 'person interested,' which means they must demonstrate a direct interest in the subject matter of the patent, such as being engaged in the same field of technology or business. The opposition is filed in Form 7 in duplicate, along with the prescribed fee, a statement of opposition, and supporting evidence. As highlighted in the Delhi High Court's ruling on intellectual property in the OpenAI case, IP law in India continues to evolve, making it important for patent challengers to stay current with legal developments.

Grounds for Opposition Under Section 25

Both pre-grant and post-grant opposition can be filed on any of the grounds specified in Section 25(1)(a) to (k) and Section 25(2)(a) to (k) respectively. These grounds include: wrongful obtaining of the invention from the opponent or a person under whom the opponent claims, anticipation by prior publication, anticipation by prior date (where the complete specification was filed before the priority date of the applicant's claim), prior claiming in any specification filed in India, prior public knowledge or public use in India before the priority date, obviousness and lack of inventive step having regard to the state of the art, non-patentable subject matter under Section 3 or Section 4, insufficiency of the description of the invention in the complete specification, failure to disclose information required under Section 8 or furnishing materially false information, failure to file the patent application within twelve months of filing in a convention country, non-disclosure or wrongful mention of the source and geographical origin of biological material, and anticipation having regard to the knowledge of any community anywhere in the world regarding traditional knowledge.

Forms and Filing Fees

Following the Patent (Amendment) Rules, 2024, which came into effect on March 15, 2024, the fee structure for patent opposition has been revised significantly. For pre-grant opposition filed in Form 7A, the fee is Rs. 4,000 for natural persons, startups, small entities, and educational institutions, and Rs. 20,000 for others. Previously, no fee was charged for filing pre-grant opposition. For post-grant opposition filed in Form 7, the fee is Rs. 8,000 for natural persons, startups, small entities, and educational institutions, and Rs. 40,000 for others. These fees represent a substantial increase from the earlier amounts and are intended to discourage frivolous filings while maintaining the opposition mechanism as a meaningful check on patent quality. For understanding how appellate processes work in different legal contexts, see our guide on filing an appeal before NCLAT against an NCLT order.

Opposition Board in Post-Grant Opposition

In post-grant opposition proceedings, the Controller constitutes an Opposition Board consisting of three members upon receiving the notice of opposition. One of the members is designated as the Chairman of the Board. The Opposition Board examines the notice of opposition, the statement and evidence filed by the opponent, and the reply statement and evidence filed by the patentee. The Board then submits its recommendations to the Controller, who is not bound by the recommendations but must consider them while passing the final order. The Opposition Board does not play a role in pre-grant opposition proceedings, where the Controller directly examines the representation and passes orders.

Evidence and Hearing Procedure

In pre-grant opposition, after the Controller determines that the representation is maintainable, notice is sent to the patent applicant, who has two months to file a reply statement and evidence. The Controller may then hear both parties before passing an order. In post-grant opposition, the procedure is more detailed. After the notice of opposition is filed, the patentee has two months to file a reply statement and evidence. The opponent may then file evidence in reply. After the evidence stage is completed, the Controller gives both parties an opportunity to be heard. The hearing is usually conducted at the appropriate Patent Office where the application or patent is registered. The Controller passes a reasoned order either maintaining or revoking the patent. This order can be appealed to the High Court. For insights into challenging quasi-judicial decisions, our article on challenging an arbitration award under Section 34 provides useful context.

Timeline for Patent Opposition Proceedings

The timeline for patent opposition varies depending on the type of opposition. For pre-grant opposition, there is no fixed deadline for filing, as it can be filed anytime between publication and grant. However, the applicant's response period is two months from the date of notice. Under the 2024 amendment, applications facing pre-grant opposition are now examined under the expedited examination provision, which significantly speeds up the process. For post-grant opposition, the filing window is one year from the date of publication of the grant. The overall proceedings, including evidence and hearing, can take 12 to 24 months depending on the complexity of the case and the workload of the Patent Office.

Key Changes Under the Patent (Amendment) Rules, 2024

The Patent (Amendment) Rules, 2024, published in the Gazette of India on March 15, 2024, introduced several important changes to the opposition framework. First, fees were introduced for pre-grant opposition for the first time, ending the previously free filing system. Second, the applicant's response time for pre-grant opposition was reduced from three months to two months. Third, applications facing pre-grant opposition are now processed under the expedited examination track. Fourth, fees for post-grant opposition were increased substantially. These changes reflect the government's intent to streamline opposition proceedings while reducing the misuse of the process for delaying patent grants. The evolving landscape of IP protection in India, including developments in trademark counterfeiting damages and personality rights protection, shows the increasing sophistication of Indian IP law.

Practical Tips for Filing Patent Opposition

Filing a successful patent opposition requires careful preparation. Opponents should conduct a thorough prior art search before filing, engage a qualified patent agent or attorney experienced in opposition proceedings, ensure that all grounds of opposition are clearly articulated and supported by evidence, file the opposition well within the statutory time limits, and be prepared for the hearing stage with persuasive legal arguments. For pre-grant opposition, the absence of a requirement to prove 'person interested' status makes it an accessible tool for public interest organizations. For post-grant opposition, demonstrating 'person interested' status is essential and should be established clearly in the opposition documents. In broader legal contexts, tools such as public interest litigation can complement patent opposition strategies where public health or traditional knowledge issues are involved.