Overview of Patent Opposition
The Indian Patents Act, 1970 provides mechanisms for third parties to challenge patent applications both before and after grant. These opposition proceedings are administrative mechanisms designed to ensure that only valid patents that meet all statutory requirements are granted or maintained.
Patent opposition serves as an important check on the patent system, allowing interested parties to challenge patents that should not have been granted due to lack of novelty, inventive step, or other grounds. This helps maintain the quality of the patent system and prevents unjustified monopolies.
Types of Patent Opposition in India
Pre-Grant Opposition
Filed after publication of application but before grant of patent. Available to any person.
Post-Grant Opposition
Filed within 12 months from the date of publication of grant. Requires legitimate interest.
Pre-Grant Opposition
Pre-grant opposition under Section 25(1) of the Patents Act allows any person to oppose a patent application after its publication but before the grant of the patent. This is a cost-effective mechanism to prevent grant of undeserved patents.
Who Can File
Any person (individual, company, or entity) can file a pre-grant opposition. There is no requirement to demonstrate interest or standing. Even competitors, public interest groups, or any concerned party can file.
Timeline for Filing
- • Opposition window: From publication of application until grant of patent
- • Publication typically occurs 18 months from priority/application date
- • No specific deadline - can be filed anytime before grant
- • Earlier filing is strategically advantageous
Procedure for Pre-Grant Opposition
Step 1: Draft Opposition
Prepare statement of opposition (Form 7A) specifying the grounds and supporting evidence.
Step 2: File Opposition
Submit opposition to the Patent Office with prescribed fee (no government fee for pre-grant opposition).
Step 3: Notification to Applicant
Controller notifies applicant, who must file reply statement and evidence within 3 months.
Step 4: Evidence and Hearing
Both parties file evidence. Controller schedules hearing and decides on grant or refusal.
Advantages of Pre-Grant Opposition
- • No government filing fee
- • Lower burden of proof compared to post-grant
- • No requirement to show interest or standing
- • Can prevent grant of problematic patents early
- • Generally faster process than post-grant opposition
Post-Grant Opposition
Post-grant opposition under Section 25(2) allows interested persons to challenge a patent within 12 months from the date of publication of the grant of the patent. This is available only for a limited window after grant.
Who Can File
Only "any person interested" can file post-grant opposition. This includes persons engaged in or promoting research in the same field as the patent. The opponent must demonstrate a legitimate commercial or public interest in the outcome.
Timeline for Filing
- • Strict deadline: Within 12 months from publication of grant
- • Publication of grant occurs after patent is sealed
- • No extension possible - deadline is absolute
- • Check patent journal for exact grant date
Procedure for Post-Grant Opposition
- 1. File Notice of Opposition: File Form 7 with prescribed fee within 12 months
- 2. Statement of Opposition: File detailed grounds within prescribed time
- 3. Reply by Patentee: Patentee files reply statement within 2 months
- 4. Evidence Stage: Both parties file evidence by way of affidavits
- 5. Hearing: Oral hearing before the Controller
- 6. Decision: Controller maintains or revokes the patent
Comparison: Pre-Grant vs Post-Grant
| Aspect | Pre-Grant | Post-Grant |
|---|---|---|
| Who can file | Any person | Person interested only |
| Time limit | Before grant (flexible) | 12 months from grant (strict) |
| Government fee | Nil | ₹2,400 - ₹12,000 |
| Evidence procedure | Flexible | Structured evidence rounds |
Grounds for Opposition
Both pre-grant and post-grant opposition can be filed on any of the grounds specified in Section 25 of the Patents Act:
Substantive Grounds
1. Wrongful Obtaining
The invention was wrongfully obtained from the opponent or from a person from whom the opponent derives title.
2. Anticipation by Prior Publication
The invention was published before the priority date in any document anywhere in the world.
3. Prior Public Use
The invention was publicly known or publicly used in India before the priority date.
4. Lack of Novelty
The claimed invention lacks novelty as it is anticipated by prior art or previously claimed in another Indian patent.
5. Lack of Inventive Step
The invention is obvious to a person skilled in the art having regard to prior art.
6. Lack of Industrial Application
The invention is not capable of being made or used in any kind of industry.
Other Grounds
- 7. Non-Patentable Subject Matter: The invention falls within excluded categories (Section 3 and 4)
- 8. Insufficient Disclosure: The specification does not sufficiently and fairly describe the invention
- 9. Failure to Disclose Foreign Applications: Applicant failed to disclose information about foreign applications as required
- 10. Convention Application Issues: Convention application filed beyond 12 months of first filing
- 11. Wrongful Mention of Inventor: True and first inventor not properly named
- 12. Double Patenting: Claimed invention already covered by another patent with same priority
- 13. False Suggestion: Specification includes false suggestion or representation
Most Common Grounds Used
- • Lack of novelty (prior publication or public use)
- • Lack of inventive step (obviousness)
- • Non-patentable subject matter (Section 3 objections)
- • Insufficient disclosure in specification
Opposition Procedure
The opposition procedure is quasi-judicial and follows specific timelines and requirements for filing documents and evidence.
Timeline for Post-Grant Opposition
| Stage | Time Limit | Document |
|---|---|---|
| File Notice of Opposition | Within 12 months of grant | Form 7 |
| File Written Statement | Within 2 months of notice | Statement of grounds |
| Reply by Patentee | Within 2 months | Reply statement |
| Evidence in Support | Within 2 months of reply | Affidavit with exhibits |
| Evidence in Reply | Within 2 months | Patentee's evidence |
| Hearing | After completion of evidence | Oral arguments |
Flexibility in Timelines
- • Extensions may be sought under Rule 138 for sufficient cause
- • Maximum extension typically 1 month at a time
- • Repeated extensions may be refused
- • Abandonment if timelines not complied with
Evidence and Hearings
Evidence in patent opposition is typically filed by way of affidavit along with supporting documents as exhibits.
Types of Evidence
Documentary Evidence
- • Prior art documents (patents, publications)
- • Sales and manufacturing records
- • Technical standards and textbooks
- • Expert opinions
Witness Evidence
- • Affidavits of technical experts
- • Testimony of persons skilled in the art
- • Evidence of prior user
- • Inventor testimony
Hearing Process
- 1. Notice of Hearing: Controller issues notice with date, time, and venue
- 2. Written Arguments: Parties may submit written briefs before hearing
- 3. Oral Hearing: Each party presents arguments through patent agent/advocate
- 4. Controller Questions: Controller may ask clarifying questions
- 5. Post-Hearing Briefs: Additional written submissions if permitted
Appeal and Revocation
If dissatisfied with the opposition decision, parties have recourse to appeal or alternative revocation mechanisms.
Appeal to IPAB
- • Appeal must be filed within 3 months of Controller's decision
- • Filed before the Intellectual Property Appellate Board (IPAB)
- • IPAB has technical and legal members for comprehensive review
- • Fresh evidence generally not allowed
- • IPAB can confirm, reverse, or modify Controller's order
Revocation Petition
Even after the 12-month opposition window expires, a patent can be challenged through:
- • Revocation under Section 64: Can be filed before IPAB or High Court on specified grounds
- • Counter-claim in Infringement Suit: Defendant can seek revocation
- • Revocation for Non-Working: Compulsory licensing-related revocation
Revocation vs Opposition
Revocation is available throughout the patent term (unlike opposition which has time limits). Revocation can be filed in High Court or IPAB, while opposition is only before the Controller. Revocation proceedings are typically more expensive and time-consuming than opposition.
Strategic Considerations
Patent opposition requires careful strategic planning to maximize chances of success while managing costs.
When to Oppose
Favor Pre-Grant When:
- • Strong prior art available
- • Cost is a concern
- • Want to prevent grant entirely
- • Patent directly threatens your product
Favor Post-Grant When:
- • Patent granted despite pre-grant opposition
- • Need stronger challenge mechanism
- • Have substantial commercial interest
- • Want comprehensive evidence procedure
Cost-Benefit Analysis
- • Opposition costs: ₹1-5 lakhs depending on complexity
- • Compare with potential licensing costs or redesign costs
- • Consider impact on competitor's patent portfolio
- • Evaluate chances of success based on prior art strength
- • Factor in time value - opposition can take 2-4 years