Under the recently amended Patents Act 1983, interested parties have the option of commencing post-grant patent opposition proceedings against granted patents before the Malaysian Intellectual Property Office (“MyIPO”). The amendments were introduced through the Patents (Amendment) Act 2022 and the Patents (Amendment) Regulations 2022, and came into effect on 31 December 2025. Since then, MyIPO has put in practice the applicable procedures and fees.
With the introduction of the post-grant patent opposition regime under the amended Patents Act 1983, interested parties now have the option of challenging a granted patent before MyIPO without having to commence invalidation proceedings in the High Court.
The introduction of opposition proceedings is expected to, to an extent, change the manner in which patent portfolios are managed.
Key Takeaways
- Malaysia's post-grant patent opposition regime took effect on 31 December 2025 under the Patents (Amendment) Regulations 2022.
- Any “interested person” may file an opposition within a strict, non-extendable six-month window from publication of the grant.
- Grounds for opposition are limited to the grounds set out in Section 56(2)(a) to (c) of the Patents Act 1983 — patentability, sufficiency of disclosure, and lack of any drawings necessary for understanding the claimed invention.
- The opposition procedure follows a structured, evidence-based sequence before the Registrar, with defined timelines for counterstatement and reply.
- Opposition proceedings provide a route for an interested party to challenge the validity of a patent at the Patent Office, instead of previously being limited to commencing invalidation proceedings at the High Court.
- Sound strategy for patent owners now includes active portfolio monitoring, not just prosecution and enforcement.
Historically, any aggrieved party wishing to invalidate a Malaysian patent had to commence High Court proceedings — a route that often proves to be costly, protracted, and commercially disruptive both to the patent owner as well as the party seeking to commercialise competing products.
What Is Malaysia's Post-Grant Patent Opposition Regime?
Malaysia's post-grant patent opposition regime, introduced under Sections 55A and 56A of the Patents Act 1983 (as amended), allows any “interested person” to challenge the validity of a granted patent before the Registrar of Patents, rather than through court litigation.
A court-based invalidation action requires the challenger to show status as an “aggrieved person”. Although the threshold to cross is low even for an “aggrieved person”, the use of “interested party” in the post-grant opposition regime suggests an even lower threshold to establish.
The opposition must be filed within six months from the date the grant is published in the IP Official Journal, and this deadline is non-extendable. Filings are, at present, handled outside the online portal — opposition-related documents must be delivered by hand or by post, with hand-delivered submissions received after 3:00 pm treated as filed on the next working day. Given the strict window, this logistical detail matters more than it might first appear.
Grounds for Opposition
Opposition proceedings are not open-ended; the statutory grounds are narrower than those available in a court invalidation action. An opposition may be brought where:
- The claimed subject matter is not patentable — including not meeting the definition of an invention under Section 12 of the Patents Act 1983, being a non-patentable invention under Section 13, being contrary to public order or morality under Section 31(1), or failing to comply with the requirements of patentability under Sections 11, 14, 15 and 16 of the Patents Act 1983.
- The description or claims are insufficiently disclosed or fail to meet regulatory drafting requirements.
- Essential drawings have not been furnished with the application.
Notably, the ground available in court proceedings under Section 56(2)(d) — that the right to the patent does not belong to the patentee — is not available in the administrative opposition process. This reflects a deliberately narrower mandate for the Registrar compared to the courts, and it is a distinction patent owners and their advisers should keep in mind when assessing where a dispute is likely to be litigated.
Opposition Procedure: How It Works
The opposition procedure is a structured, largely written, inter partes process administered by the Registrar, assisted where necessary by an ad hoc Opposition Committee.
| Stage | Party | Timeline |
|---|---|---|
| Notice of Opposition filed | Opponent | Within 6 months of grant publication (non-extendable) |
| Counterstatement | Patent owner | 3 months from Registrar's notice of opposition |
| Evidence in reply | Opponent | 3 months from counterstatement or amendment |
| Committee review | Ad hoc Opposition Committee | As convened by Registrar |
| Decision | Registrar | Maintain, maintain with amendments, or revoke |
| Appeal | Either party | To the High Court |
A few procedural features are worth flagging for anyone managing a live or anticipated opposition:
- Security for costs is mandatory for foreign opponents. A non-resident interested person must lodge RM2,500, or RM1,500 for utility innovations, at the time of filing, in addition to standard filing fees. Failure to furnish security can result in the opposition being rejected outright.
- Cannot run in parallel. Opposition and court proceedings on the same patent cannot run in parallel. If litigation is already underway, an opposition cannot be launched; conversely, filing an opposition generally bars the opponent from starting court proceedings unless both parties consent, or the opponent is later sued for infringement.
- Patent owners may amend a patent during opposition proceedings. Filing a request to amend the patent — to narrow claims or address the grounds raised — is often a more strategic response than contesting the opposition outright on the original claim scope. However, such a request to amend the patent can only be made for the purpose of responding to the notice of opposition and any additional ground of opposition, and is subject to the Registrar’s discretion.
- Finality has teeth. If the Registrar upholds the patent, the opponent is generally barred from later bringing invalidation proceedings in court, except as a counterclaim in infringement litigation or on appeal under Section 88.
Greater Transparency of Patent Filings
Public inspection under Section 34 of the Patents Act 1983 has also been amended. Once an application is published, members of the public may inspect a broader set of documents than before — including search and examination reports, and communications regarding the patent application from the applicant to the Patent Office, subject to the Registrar's discretion.
Where the application has not yet reached 18 months from the filing or priority date, and where the applicant has not requested early publication, inspection of materials related to the application requires the applicant's written permission.
This has two practical implications for Malaysian patent portfolios. First, a member of the public will be able to view any amendments made to a particular application, and the objections raised by the Patent Examiner during the examination stage. Second, the patent owner may be committed to the rationale and interpretation it has adopted during the amendment stage.
Strategy for Patent Owners in View of Opposition Proceedings
Opposition proceedings shift patent risk management from a largely reactive posture — waiting for an infringement dispute or an invalidation — to one that requires active monitoring over a six-month period. In practice, there is also the need to monitor the publication of the grant in the Journal, which can typically take between one and three months.
A sound strategy for patent owners under the new framework typically involves:
- Auditing recently granted patents. If a grant was published within the last six months, the patent remains within the opposition window and should be reviewed for vulnerabilities before a third party does the same.
- Monitoring the MyIPO Official Journal systematically. Because the six-month window is strict and non-extendable, missing a competitor's newly granted patent means losing the most cost-effective opportunity to challenge it.
- Assessing claim scope and prosecution history early. Where a competitor's patent poses a commercial threat, an early technical and legal assessment of claim strength — before the opposition window closes — preserves the option of an opposition proceeding rather than defaulting to costlier litigation.
Best Practices for Patent Owners
Are opposition proceedings always preferable to litigation?
Not necessarily. While opposition proceedings under Section 55A offer a less costly and less formal route, the grounds for opposing are more limited compared to court-led invalidation proceedings. The facts surrounding each granted patent have to be assessed on their own.
For example, the duration of the opposition proceedings may be lengthened due to the filing of a counterstatement and any request to amend the patent. Furthermore, an interested party has the option to withdraw the notice of opposition and then commence invalidation proceedings at court, depending on the circumstances and whether infringement proceedings are already contemplated.
What happens if an interested person misses the six-month window?
Once the six-month opposition window from publication of the grant closes, an interested person generally cannot use the opposition proceedings and must fall back on court invalidation proceedings, which remain more time-intensive and costly.
Can a patent be amended during opposition?
Yes. As mentioned earlier, the patent owner may file a request with the Registrar to amend the patent during proceedings, but only to address the notice of opposition. Alternatively, at the end of proceedings, the Registrar may allow the patent owner to request to amend the patent, within the scope specified by the Registrar, in order to maintain it. In both circumstances, the request to amend is subject to the Registrar’s discretion.
Do opposition proceedings affect patent applicants, not just granted patent owners?
By itself, no. However, when taken into consideration with the widened scope of public inspection under Section 34 of the Patents Act 1983, applicants should anticipate that the arguments and amendments made during prosecution may be viewed by an interested party to form the basis for subsequently filing a notice of opposition after the patent is granted.
Conclusion
Malaysia's post-grant patent opposition regime marks one of the most significant procedural developments in the country's patent landscape in recent years. For patent owners, it introduces both a new exposure — a faster, more accessible route for competitors to challenge newly granted patents — and a new tool, allowing owners to challenge a rival's patent via MyIPO rather than through prolonged litigation.
Navigating the strict timelines, the narrower statutory grounds, and the strategic choice between opposition and court proceedings calls for careful, case-specific advice.
Shearn Delamore & Co.'s Intellectual Property team advises patent owners and applicants on prosecution, portfolio management, and contentious patent matters, including opposition and invalidation proceedings before MyIPO and the courts.
If you would like to discuss how the new post-grant opposition regime may affect your patent portfolio or a competitor's recent grant, please get in touch with our team.
