Who has standing to bring an invalidity action against a patent? Is any particular connection to the patentee or patent required?

Patent Litigation

Australia Small Flag Australia

Any party can seek revocation of a patent in the Federal Court of Australia.

Austria Small Flag Austria

Everybody can bring an invalidity action against a patent. However, if the patent expired during invalidity proceedings, the applicant has to establish a legal interest in continuing proceedings (e.g. because he is involved in parallel infringement proceedings).

Brazil Small Flag Brazil

Anyone with a proven legitimate interest, including the Brazilian PTO. For instance, in 2013, the BRPTO filed 37 lawsuits seeking the invalidity of mailbox patents that were granted, according to the BRPTO, with a wrong patent term.

Canada Small Flag Canada

Impeachment proceedings may be commenced by ‘any interested person’ (Patent Act, s. 60), which has been interpreted broadly to include any person who is in competition with the patentee, who has been sent a cease and desist letter, or who has been otherwise accused of infringing a claim of the patent.

China Small Flag China

Anyone can bring an invalidity action against a patent, and the he would not have to have any particular connection to the patentee or patent required.

Czech Republic Small Flag Czech Republic

Any person can request a cancellation of the patent at the IPO. A valid legal interest must be proven if the cancellation application is to take place after patent expiry.

France Small Flag France

IPC does not contain specific provisions on whom has standing to commence a patent invalidity action. Reference should thus be made to Article 31 of the Code of Civil Procedure providing that "the action is open to anyone who has a legitimate interest in the success or rejection of a claim".

In practice, the claimant for invalidity action is most often a competitor who enacts to free the market and avoid the risk of a possible infringement action against its future product or process.

Germany Small Flag Germany

Everybody has standing to bring an invalidity action in Germany. No legal interest etcetera needs to be shown.

However, after the lapse of patent, only a party showing a specific legal interest to have the patent retroactively invalidated can still bring an invalidity action. Such legal interest may be a potential threat of damages for past use.

Greece Small Flag Greece

Any party having legitimate interest is entitled to request nullification of a patent. If a nullity action against a patent has already been filed, it will be much more difficult for the patent owner to succeed in preliminary proceedings. There is no assumption that the patent is valid and protected. Further, the party can rely on the argumentation already included in the nullity action. If the patent owner subsequently files a main infringement action, both nullity and infringement actions will likely be heard together. If the patent owner has already filed a main infringement action, the defendant has the right to dispute the validity of the patent and to file prior art documents and other evidence, such as expert opinions).

India Small Flag India

a) Under Section 25(1) of the Patents Act, 1970 which provides for a pre-grant opposition, any person may oppose against the grant of a patent;

b) Under Section 25(1) of the Patents Act, 1970 which provides for a post-grant opposition, any person interested may oppose against the grant of a patent;

c) Under Section 64 of the Patents Act, 1970 which provides for revocation, if the revocation is filed before the Intellectual Property Appellate Board, the same may be filed a person interested or by the Central Government. Further, the defendant in a law-suit can seek revocation of a Patent through a counter-claim.

Ireland Small Flag Ireland

Any person has standing to bring an invalidity action against a patent.

Israel Small Flag Israel

Under the Patents Act, "any person" (a person is defined to include also a corporation) has standing to bring an invalidity challenge against a patent.

Italy Small Flag Italy

Like all civil actions, a revocation action must be assisted by an interest into bringing legal proceedings. The ‘test’ applied to patent revocation/invalidity actions is however rather generous. The practical result is that virtually anyone can apply for patent revocation.

Japan Small Flag Japan

Invalidity actions at the JPO mainly include patent oppositions and patent invalidation trials. A patent opposition may be filed by any person no later than six months from the publication date of the Gazette for the patent. A demand for a patent invalidation trial may only be filed by an interested party any time after the grant of the patent (which also covers the time period after the expiration of the patent term). From a practical viewpoint, not only the party which has actually been sued for patent infringement but also parties holding patents similar to the relevant patent and parties who manufacture the same type of product as the patented invention are deemed to be interested parties.

Norway Small Flag Norway

Pursuant to section 52 of the Patents Act, anyone may bring legal proceedings in order to invalidate a granted patent.

Poland Small Flag Poland

The applicant for invalidity is required to have legitimate interest in invalidating one’s patent. A legitimate interest is interpreted, in general, as a serious and currently existing need for invalidating a patent (e.g. if the patent is already in suit or if the applicant has undertaken serious preparations to use the solution according to the patent). It is claimed that this interest needs to be real and imminent.

The legitimate interest has been the major obstacle in invalidating patents in Poland which resulted in broad and complex case-law of the administrative courts.

Portugal Small Flag Portugal

The Public Prosecutor’s office or any interested party (which is usually demonstrated by the fact that they intend to exploit the invention) are entitled to bring an invalidity action.

Russia Small Flag Russia

Any person can file an invalidity action against Russian or Eurasian patent, based on the lack of patentability or presence of new matter in the claim. Such «patentability» action is to be filed with the RUPTO. An invalidity action based on wrong inventorship can be filed with the IP Court only by an interested party (normally one who claims his own inventorship or otherwise economically suffers from wrong attribution of the inventorship).

Singapore Small Flag Singapore

The following persons may bring an invalidity action against a patent:

(a) defendants of a patent infringement proceeding are entitled to challenge the validity of the patent holder’s patent by way of defence. In the recent Court of Appeal decision, Sunseap Group Pte Ltd and others v Sun Electric Pte Ltd [2019] 1 SLR 645, the Court of Appeal has held that the Singapore High Court has the original jurisdiction to revoke an invalid patent only in proceedings where the validity of the patent was put in issue by way of a defence.

(b) applicants of a groundless threat of infringement proceeding under section 77 of the PA may challenge the invalidity of a patent. However, these applicants must have had their commercial interests adversely affected or likely to be adversely affected. The defendant can be any persons and need not be limited to only the proprietor of the patent or a person that is entitled to any right in a patent, for example, a licensee;

(c) applicants who applied for a declaration of non-infringement under section 78 of the PA;

(d) applicants who applied to revoke the patent pursuant to any or all of the grounds set out in section 80 of the PA. Although any person may bring a revocation application, an applicant must establish a cause of action entitling him to a ruling on validity since no proceedings may be instituted solely to seek a declaration as to the validity or invalidity of a patent ; and

(e) The Government or parties authorised by the Government involved in proceedings relating to the use of patented inventions by the Government and its authorised parties under sections 56 and 58 of the PA. Section 56 of the PA provides that the use of a patented invention by the Government or its authorised party would not constitute an infringement of the patent if done (a) for a public non-commercial purpose or (b) for/during a national emergency or other circumstances of extreme urgency.

Do note that these applications must be made to the IPOS Registry, with the exception of (a) above which must be made to the High Court (see also the answers made to question 16 above).

South Korea Small Flag South Korea

An interested party can initiate a patent invalidation action before the IPTAB. An interested party may be an alleged infringer, as well as an entity that is producing or will produce a product that has some relationship to the patent claims. Receipt of a warning letter or notice of patent is not necessary to have standing to bring an invalidation action.

Sweden Small Flag Sweden

Anyone for whom the patent is detrimental has standing to bring an invalidity action. When an invalidity action is brought, the plaintiff must report this to the Patent Authority and notify all registered licensees and pledgees.

Switzerland Small Flag Switzerland

Any person with a proven legal interest may bring an invalidity action. The threshold for such legal interest is rather low. For instance, anyone who may be restricted in his economic activities by a patent has standing.

Taiwan Small Flag Taiwan

For an invalidation action on the ground that a patent does not satisfy the requirements (utility, novelty, and non-obvious), or that the amendment to a patent is not allowable, anyone is allowed to bring a such invalidation action and not required to establish any connection with the patentee or the patent.

On the other hand, however, for an invalidation action on the ground that the patentee of a patent is not a legitimate applicant (for instance, the patentee is not an inventor or the employer of the inventors), only a person or an entity having interests in the patent has standing to file an invalidation action against said patent.

Thailand Small Flag Thailand

In Thailand, patent validity can only be challenged in court. Pursuant to Section 54 of the Patent Act, any “interested party” can file a patent invalidation action to challenge the validity of a Thai patent any time after the patent is granted and before it expires.

The party challenging the patent must be able to demonstrate that it is an “interested party,” though this hurdle easy to overcome. For example, a plaintiff could assert that it is injured in some way by incorrect restrictions to the market by virtue of the existence of the patent.

Turkey Small Flag Turkey

Any party who has benefit, Public Prosecutors or relevant establishments and institutions are entitled to request the invalidation of a patent. The required benefit is not high, as the registry is deemed to be related to the public order, almost everyone is deemed to have the right to file an invalidation action, and it is not necessary to prove any particular connection to the patentee or the subject patent.

United Kingdom Small Flag United Kingdom

European patents with UK designations can be invalidated in the UK by the court or the Comptroller, or centrally by the EPO. Only a UK court or the Comptroller can invalidate a UK patent granted nationally by the UK IPO.


Under Article 99 EPC, for the nine months following the grant of a European patent, any person can file an opposition in the EPO to the grant of that patent. Any person can file an EPO opposition and, as a matter of practice, the identity of the opponent can remain anonymous if the opposition is filed in the name of a “straw man”, such as the European patent attorney firm that represents it, as is often the case.


An application to revoke a granted UK patent can be made before the UK courts or the Comptroller. While it is common for a defendant to an infringement proceeding to bring a counter-claim for invalidity, a revocation action can in fact be brought assertively, and in the absence of an actual or threatened controversy.

Any person may bring an invalidity action in respect of a patent in the UK under any of the grounds specified under Section 72(1) Patents Act, save in respect of patent entitlement, pursuant to Section 72(1)(b).

Under Section 72(2)(a), an application to revoke a patent on the ground that it was granted to a person who was not entitled to be granted that patent may only be made by a person found by the court or the Comptroller to be entitled to be granted that patent or to be granted a patent for part of the matter comprised in the specification of the patent sought to be revoked. Under Section 72(2)(b), such an application may not be made if that action was commenced or that reference was made after the second anniversary of the date of the grant of the patent sought to be revoked, unless it is shown that any person registered as a proprietor of the patent knew at the time of the grant or of the transfer of the patent to him that he was not entitled to the patent.

Section 74 Patents Act specifies the types of proceedings in which the validity of a patent may be put in issue (by way of defence, proceedings for infringement under Section 61 or Section 69; proceedings in respect of an actionable threat under Section 70A; proceedings in which a declaration is sought under Section 71; proceedings for the revocation of the patent under Section 72; and proceedings involving Crown use under Section 58). Accordingly, while (with the exception of the entitlement issue) any person may bring an action for invalidity pursuant to Section 72, not every person can necessarily be a party to every such type of proceeding.

United States Small Flag United States

In order to initiate a patent lawsuit in a federal district court on the basis of invalidity, the plaintiff needs to demonstrate that it faces a definite and concrete allegation of infringement by the patent owner. Without this, the court may dismiss the case for lack of declaratory judgment jurisdiction and lack of subject matter jurisdiction.

Any entity (other than the patent owner) may initiate an IPR, CBM, PGR, or derivation proceeding. An IPR petition must be filed after nine months of the challenge patent’s grant date, and a PGR petition must be filed within that nine-month period. A CBM challenge may be filed any time, but only if the challenger has been sued or charged with infringement. An ex parte re-examination proceeding may be filed any time by any entity, including the patent owner.

Vietnam Small Flag Vietnam

Normally, any parties can request the IP Office to invalidate a patent. During infringement proceedings, the defendant can call on the court to review the validity of the patent.

Updated: November 14, 2019