Post-Grant Patent Opposition Proceedings: Now in Force

Malaysia Patent Opposition Update

Effective 31 December 2025    Quality Oracle Group Patent Team

Malaysia’s patent enforcement landscape changed materially on 31 December 2025. On that date, the provisions governing post-grant patent opposition proceedings under the Patents (Amendment) Act 2022 came into force, together with the Patents (Amendment) Regulations 2025. After nearly three years of legislative dormancy, Sections 55A and 56A of the Patents Act 1983 are now operational.

This update sets out what the new regime involves, who it affects, how the process works, and what patent holders and interested third parties should be doing in response.

Background: Why This Reform Matters?

Before this reform, the only way to challenge a granted Malaysian patent was through invalidation proceedings before the High Court. That route requires the challenger to qualify as an ‘aggrieved person’, a threshold that excludes many legitimate stakeholders, and involves the time and cost of full litigation.

Post-grant opposition offers a different path. Proceedings take place before the Registrar of Patents at MyIPO, are administrative rather than judicial in nature, and are open to any interested person regardless of whether they are directly affected by the patent. The threshold is lower, the forum is more accessible, and the process is designed to be faster and less expensive than Court proceedings.

Key change: Post-grant opposition is available to any interested person, not just those who can demonstrate they are adversely affected. This is a broader standing test than High Court invalidation.

Opposition proceedings are available against patents with a grant date on or after 31 December 2025. They cannot be initiated where the patent is already the subject of pending Court proceedings in which validity is in question.

Grounds for Post-Grant Opposition in Malaysia

Section 55A limits the grounds on which a post-grant opposition may be brought. These mirror the grounds available in High Court invalidation proceedings, with one notable exclusion: ownership and entitlement disputes are not available as opposition grounds before the Registrar and must still be pursued through the courts.

Permitted grounds for post-grant opposition are:

• The claimed invention does not qualify as an invention or is not patentable under Section 12 of the Patents Act (for example, it lacks technical character or does not solve a technical problem)
• The invention falls within excluded subject matter under Section 13 or Section 31(1), including discoveries, scientific theories, mathematical methods, plant or animal varieties, business methods, mental acts, and treatment or diagnostic methods practised on the human or animal body
• The invention fails to satisfy the patentability requirements of novelty, inventive step, or industrial applicability under Sections 11, 14, 15 and 16
• The description or claims are deficient, including grounds of lack of sufficiency or lack of support for the claims
• Drawings essential to understanding the invention were not provided

How the Opposition Process Works?

The procedural steps are set out in new Regulations 43A through 43U of the Patents Regulations 1986, as amended. The timeline is strict: once the 6-month opposition window closes, no extension is available.

The 6-month filing window for the Notice of Opposition runs from the date of publication of patent grant in the Intellectual Property Official Journal (IPOJ). No extension of time to this deadline is permitted under any circumstances.

Expanded Public Access: What Changed Under Section 34?

Amended Section 34 of the Patents Act, which also came into force on 31 December 2025, significantly expands the information available for public inspection at MyIPO. In addition to the application details previously accessible, the Registrar must now make the following available:

• Search and examination reports issued during prosecution of the patent application
• Written communications from the applicant to the Patent Registration Office (as determined by the Registrar)
• Patent and non-patent literature citations submitted by the applicant or any other person during prosecution

This represents a material increase in prosecution transparency. For third parties assessing whether to file an opposition, access to examination history, including prior art citations and examiner correspondence, strengthens the ability to build a case before the grant date.

What Patent Holders Should Do Now?

The introduction of post-grant opposition raises the exposure profile of Malaysian patents granted from 31 December 2025 onwards. Patent owners should take the following steps:

1. Review agent-on-record details

MyIPO will only serve a Notice of Opposition on the patent agent currently on record. Where assignments, recordals of change, or renewal delegations have resulted in a different agent being listed, any opposition notice will go to that agent, potentially causing critical delay before it reaches the actual rights holder or their advisers. Confirm that the correct agent is on record for each patent in your Malaysian portfolio.

2. Assess prosecution risk for recently granted patents

Patents that proceeded through modified examination, where the specification mirrors a corresponding foreign patent from Australia, Japan, Korea, the UK, the US, or the EPO, carry a particular consideration. If an opposition succeeds and amendment is required, the amended Malaysian specification will diverge from the foreign reference patent. The extent to which such amendments will be permissible is not yet settled.

3. Build a response-ready approach for patents in prosecution

For patent applications currently in prosecution, prior art cited in examination reports from corresponding foreign applications is particularly relevant, as it can form the basis of a future opposition challenge. Addressing such prior art clearly during prosecution reduces exposure.

4. Consider divisional and conversion strategies

Filing a voluntary divisional application as a protective measure remains available within a strictly non-extendible three-month window from the mailing date of the first Examination Report. Additionally, conversion of a patent application to a utility innovation registration can offer a more defensible position given the lower registrability threshold (novelty only, no inventive step requirement) and single-claim structure of Malaysian utility innovations.

What Third Parties and Competitors Should Do Now?

For parties managing competitor patent risk in Malaysia, the new regime creates both opportunity and a tight operational window.

1. Establish a patent watch service

The 6-month opposition window begins from IPOJ publication of the grant. Monitoring the IPOJ for grants in relevant technology areas is now essential if opposition is a potential strategy. A watch service should be set up before a patent of concern proceeds to grant, not after.

2. Access prosecution files proactively

MyIPO provides public access to direct national applications 18 months after the priority date. PCT national phase applications are not published in the IPOJ, but their specifications and prosecution status can be accessed separately. Note: accessing application files through IP Online may inadvertently alert the applicant due to system notifications, so parties wishing to maintain confidentiality should take this into account.

3. Prepare evidence before the grant date

Given the short, non-extendible filing window, evidence gathering and grounds preparation should ideally begin during prosecution. The expanded access to examination history under amended Section 34, including prior art citations and examiner correspondence, provides useful material for this purpose.

Unresolved Questions: Areas to Watch

The procedural framework is now in place, but implementation will develop over time as MyIPO handles its first oppositions. Several practical questions remain open:

• Multiple opponents: the regulations do not expressly address whether proceedings brought by more than one opponent against the same patent will be consolidated or handled separately.
• Timeline for committee formation and decisions: the regulations establish the process but do not set binding timeframes for the Opposition Committee to convene or for the Registrar to issue a decision.
• Estoppel: it is not yet clear whether an unsuccessful opponent will be estopped from raising the same grounds in subsequent High Court invalidation proceedings.
• Scope of permissible amendments: for patents that underwent modified examination, the extent of amendments that MyIPO will allow during opposition, without the specification diverging impermissibly from the reference foreign patent, has not been tested.

Key Takeaways

• Post-grant patent opposition came into force in Malaysia on 31 December 2025 under the Patents (Amendment) Act 2022 and Patents (Amendment) Regulations 2025.
• Any interested person may file an opposition before the Registrar of Patents at MyIPO; the “aggrieved person” threshold that applies to High Court invalidation does not apply here.
• The Notice of Opposition must be filed within 6 months of patent grant publication in the IPOJ. The deadline is strict and no extension is available.
• Opposition is available only against patents with a grant date on or after 31 December 2025, and is not available where Court validity proceedings are already pending.
• Amended Section 34 expands the prosecution information available for public inspection, including examination reports and prior art citations.

FAQs

When did post-grant patent opposition come into force in Malaysia?

Post-grant patent opposition came into force on 31 December 2025, when the relevant provisions of the Patents (Amendment) Act 2022 and the Patents (Amendment) Regulations 2025 took effect. Sections 55A and 56A of the Patents Act 1983 are now operational.

Who can file a post-grant patent opposition in Malaysia?

Any interested person may file an opposition before the Registrar of Patents at MyIPO. Unlike High Court invalidation proceedings, the opponent is not required to qualify as an “aggrieved person” or demonstrate that they are directly affected by the patent. Non-residents must provide security for costs at filing.

What is the deadline to file a Notice of Opposition?

The Notice of Opposition must be filed within 6 months of the date of publication of patent grant in the Intellectual Property Official Journal (IPOJ). This deadline is strict and no extension of time is permitted under any circumstances.

Which Malaysian patents can be opposed under the new regime?

Opposition proceedings are available against patents with a grant date on or after 31 December 2025. Opposition cannot be initiated where the patent is already the subject of pending Court proceedings in which validity is in question.

What are the grounds for post-grant opposition?

Permitted grounds under Section 55A include: the claimed invention is not patentable under Section 12; the invention falls within excluded subject matter under Section 13 or 31(1); failure to satisfy novelty, inventive step, or industrial applicability under Sections 11, 14, 15 and 16; deficient description or claims, including lack of sufficiency or lack of support; and missing essential drawings. Ownership and entitlement disputes are not opposition grounds and must be pursued in the courts.

How does opposition differ from High Court invalidation?

Opposition is an administrative proceeding before the Registrar of Patents at MyIPO, open to any interested person, and is designed to be faster and less expensive than litigation. High Court invalidation is a judicial proceeding, requires the challenger to qualify as an “aggrieved person,” and involves full litigation costs and timelines. Either party may appeal the Registrar’s opposition decision to the High Court within 1 month.

Quality Oracle Group will monitor early opposition practice and issue updates as MyIPO guidance and decided cases become available. Clients with questions about specific patents or portfolio positioning are encouraged to get in touch with our patent team.

Note: The information provided in this newsletter is for general informational and educational purposes only and does not constitute formal legal advice from Quality Oracle.