A patent application may pass examination and still face a challenge from another person. Indian patent law allows third parties to oppose a patent before grant and, in certain cases, after grant.
This process is known as patent opposition.
Patent opposition helps prevent patents from being granted or continued where the invention is already known, obvious, wrongly obtained, insufficiently explained or not patentable under Indian law.
There are two types of opposition:
- Pre-grant opposition
- Post-grant opposition
Both are governed mainly by Section 25 of the Patents Act, 1970, but their filing periods, eligibility and procedures are different.
What Is Pre-Grant Patent Opposition?
A pre-grant opposition is filed after a patent application has been published but before the patent is granted.
Any person may file it. The opponent does not need to prove that they are a competitor, researcher or business affected by the patent.
The opposition is filed as a written representation in Form 7A. It must include the grounds, supporting statement, available evidence and a request for hearing where the opponent wishes to be heard. A copy must also be provided to the patent applicant.
When Can a Pre-Grant Opposition Be Filed?
A pre-grant opposition may be filed:
- After publication of the patent application; and
- Before the patent is granted.
The Patent Rules state that a patent cannot be granted before six months have passed from the publication date. This gives the public a minimum period in which to study the application and file an opposition.
However, waiting until the end of six months may be risky. If the patent remains pending after that period, opposition can still be filed until the actual date of grant.
Once the Controller passes the grant order, Form 7A can no longer be used.
Is Examination Required Before Pre-Grant Opposition Is Considered?
Yes. A person may file the opposition after publication, but the Controller considers it only after a valid Request for Examination has been filed for the patent application.
The opposition is normally considered along with the examination of the patent application and the Examiner’s report.
Pre-Grant Opposition Process
Step 1: Review the Published Patent Application
The opponent should study:
- Complete specification
- Claims
- Drawings
- Abstract
- Priority details
- Patent family
- Applicant details
- Earlier documents relating to the invention
A proper opposition should focus on specific patent claims and clear legal grounds. General statements that the patent is “not new” or “should not be granted” are not enough.
Step 2: File Form 7A
The opponent files Form 7A at the appropriate Patent Office.
The representation should contain:
- Patent application number
- Details of the opponent
- Grounds of opposition
- Facts supporting each ground
- Prior-art documents
- Evidence, where available
- Relief requested
- Request for hearing, if desired
A copy must be provided to the applicant.
Step 3: Initial Consideration by the Controller
The Controller reviews the opposition along with the patent application.
If the Controller believes that the opposition has no merit, it may be rejected.
If the Controller believes that the patent application may need to be refused or amended, a notice is issued to the applicant.
Step 4: Applicant Files a Reply
After receiving the Controller’s notice, the applicant may file a statement and evidence supporting the patent application.
The applicant gets three months from the date of the notice to file the reply. A copy must also be provided to the opponent.
Step 5: Hearing
Where a hearing has been requested, both sides may present their arguments.
The opponent explains why the patent should not be granted. The applicant explains why the claims are valid and may also propose legally permitted amendments.
Step 6: Decision
After considering the application, opposition, evidence and hearing arguments, the Controller may:
- Reject the opposition and proceed with the application
- Require amendment of the claims or specification
- Refuse the patent application
The Controller must pass a reasoned order and should ordinarily decide the application and opposition within one month after the proceedings are completed.
What Is Post-Grant Patent Opposition?
A post-grant opposition is filed after a patent has already been granted.
Unlike pre-grant opposition, it cannot be filed by every member of the public. It may be filed only by a person interested.
The Act states that a person interested includes a person engaged in, or promoting, research in the same field as the patented invention. Depending on the facts, it may also include a competitor, manufacturer, licensee or business whose commercial activity is affected by the patent.
Deadline for Post-Grant Opposition
Post-grant opposition must be filed:
- After the patent is granted; but
- Within one year from the date on which the grant is published.
The one-year period is counted from the publication of the grant in the Patent Office Journal, not simply from the filing date or application-publication date.
Post-Grant Opposition Process
Step 1: File Form 7
The opponent must file a notice of opposition in Form 7.
The opponent must also file:
- A written statement
- Nature of the opponent’s interest
- Facts relied upon
- Relief requested
- Supporting evidence, if any
A copy of the written statement and evidence must be delivered to the patentee.
Step 2: Patentee Files a Reply
Where the patentee wants to contest the opposition, a reply statement and supporting evidence must be filed within two months from receiving the opponent’s written statement and evidence.
A copy must also be provided to the opponent.
If the patentee does not file the reply within the two-month period, the patent is deemed to be revoked.
Step 3: Opponent Files Reply Evidence
The opponent may file evidence in reply within one month from receiving the patentee’s reply and evidence.
This evidence must be limited to matters raised in the patentee’s evidence. It cannot be used to create a completely new opposition case.
Step 4: Further Evidence
Neither party may normally file further evidence without the permission or direction of the Controller.
Any request to file additional evidence should be made before the Controller fixes the opposition hearing.
Step 5: Opposition Board
After receiving the post-grant opposition, the Controller forms an Opposition Board consisting of three members.
The Examiner who handled the original patent application cannot be a member of that Board.
The Board studies the notice, replies, evidence and documents. It then submits a reasoned recommendation on every opposition ground, generally within three months after receiving the documents.
Step 6: Hearing
After the evidence stage and the Opposition Board’s recommendation, the Controller fixes the hearing.
Both sides must receive at least ten days’ notice.
A party that wants to attend must notify the Controller and pay the prescribed hearing fee. If a party wants to rely on a publication that was not filed earlier, details must be provided to the other party and Controller at least five days before the hearing.
Step 7: Final Decision
After reviewing the Opposition Board’s recommendation and hearing both sides, the Controller may:
- Maintain the patent as granted
- Maintain the patent with amended claims or specification
- Revoke the patent
The final decision must give reasons. Where the patent is maintained with amendments, those amendments become part of the patent.
Grounds for Patent Opposition
The legal grounds for pre-grant and post-grant opposition are broadly the same.
1. Wrongful Obtaining
The applicant or patentee obtained the invention, or part of it, from the opponent or another person through whom the opponent claims.
2. Earlier Publication
The claimed invention was published before its priority date in:
- An earlier Indian patent specification; or
- Another document published in India or elsewhere.
3. Earlier Claiming
The same invention was already claimed in an Indian patent application having an earlier priority date.
4. Earlier Public Knowledge or Use
The invention was publicly known or publicly used in India before the priority date.
5. Lack of Inventive Step
The invention is obvious and does not involve an inventive step when compared with earlier publications or earlier use.
6. Non-Patentable Subject Matter
The claim is not an invention under the Patents Act or falls under an exclusion, such as Section 3 or Section 4.
7. Insufficient Disclosure
The complete specification does not explain the invention clearly or sufficiently enough for a skilled person to perform it.
8. Failure to Meet Section 8 Requirements
The applicant failed to provide required information about corresponding foreign patent applications or knowingly supplied materially false information.
9. Incorrect Convention Deadline
A convention application was not filed within the required 12-month period.
10. Biological-Material Source
The complete specification does not disclose, or wrongly states, the source or geographical origin of biological material used in the invention.
11. Traditional Knowledge
The invention is anticipated by knowledge available within a local or indigenous community in India or another country.
Difference Between Pre-Grant and Post-Grant Opposition
Who Can File?
Pre-grant: Any person
Post-grant: Only a person interested
When Is It Filed?
Pre-grant: After publication and before grant
Post-grant: Within one year from publication of grant
Prescribed Form
Pre-grant: Form 7A
Post-grant: Form 7
Opposition Board
Pre-grant: No separate Opposition Board
Post-grant: A three-member Opposition Board is formed
Final Result
Pre-grant: Application may proceed, be amended or be refused
Post-grant: Patent may be maintained, amended or revoked
Patent Opposition Government Fees
The current electronic filing fees are:
Pre-Grant Opposition—Form 7A
- ₹4,000 for a natural person, startup, small entity or educational institution
- ₹20,000 for other persons
Post-Grant Opposition—Form 7
- ₹8,000 for a natural person, startup, small entity or educational institution
- ₹40,000 for other persons
The current fee schedule does not permit physical filing of Forms 7 and 7A. Separate fees apply where a party gives notice that it wishes to attend a post-grant opposition hearing. Government fees may change, so the latest official schedule should be checked before filing.
Evidence Commonly Used in Patent Opposition
Useful evidence may include:
- Earlier patents
- Published patent applications
- Research papers
- Technical articles
- Product catalogues
- Books and manuals
- Websites with reliable publication dates
- Invoices and sales records
- Product photographs
- Exhibition records
- Expert affidavits
- Laboratory reports
- Traditional-knowledge records
In a post-grant proceeding, evidence is generally filed through affidavits, and foreign-language documents should be accompanied by attested English translations.
Can Claims Be Amended During Opposition?
Yes, the applicant or patentee may propose amendments to overcome an opposition ground.
However, an amendment cannot freely add new technical information. It must comply with the amendment limits under the Patents Act.
The Controller may allow a patent application to proceed with amended claims or may maintain a granted patent only after suitable amendments.
Can a Post-Grant Opposition Decision Be Appealed?
Yes. An order passed by the Controller under Section 25(4) may be appealed before the appropriate High Court.
The normal appeal period is three months from the date of the Controller’s decision, although the High Court may allow additional time according to its rules.
Opposition and Revocation Are Different
Post-grant opposition is available only during the first year after publication of the grant.
Revocation is a separate challenge that may be filed before the High Court by a person interested or the Central Government, or raised as a counterclaim in an infringement suit, subject to the provisions of Section 64.
Therefore, the expiry of the post-grant opposition period does not always mean that the validity of the patent can never be challenged.
Common Mistakes in Patent Opposition
Common mistakes include:
- Filing after the permitted deadline
- Using the wrong form
- Raising grounds not allowed under Section 25
- Making general allegations without claim-wise analysis
- Relying only on abstracts instead of complete prior-art documents
- Failing to prove publication dates
- Not serving copies on the other party
- Missing the applicant’s three-month reply deadline
- Missing the patentee’s two-month reply deadline
- Filing late or unrelated evidence
- Failing to request a hearing
- Proposing amendments that add new matter
Conclusion
Patent opposition in India provides two opportunities to challenge a patent.
A pre-grant opposition may be filed by any person after publication and before grant through Form 7A. A post-grant opposition may be filed only by a person interested within one year from publication of the grant through Form 7.
The opposition must be based on one or more specific grounds provided under Section 25. Strong technical analysis, clear claim comparison and properly dated evidence are essential.
For an applicant or patentee, every opposition deadline must be handled carefully. Failure to file a proper reply in time may lead to refusal of the application or revocation of the patent.
Need help filing or defending a patent opposition? IPHelm provides professional support for prior-art analysis, Form 7A and Form 7 proceedings, opposition replies, evidence, claim amendments and hearings before the Indian Patent Office.