EP validation is a system that allows a European patent granted by the European Patent Office (EPO) to take effect in states that are not full members of the European Patent Convention (EPC). It forms a significant part of international patent strategy, particularly for companies seeking protection in markets beyond Europe through a single, centrally processed patent application.
EP validation is based on bilateral agreements between the European Patent Organisation and individual states. The system allows the effects of a European patent to be extended to a validation state without requiring a separate national patent application. Once validated, the patent has essentially the same legal effect in that state as a nationally granted patent.
When an applicant pays the validation fee within the required deadline:
The EPO highlights that the validation system offers high legal certainty, cost-effective protection in new markets, consistent examination quality, and a simpler procedure compared with separate national applications.
The EPO uses two similar but distinct terms. The extension system is an older arrangement applying to non-EPC European states — today, Bosnia and Herzegovina is the only remaining active extension state. The validation system, in place since 2010, is a newer arrangement that is not limited to Europe and enables cooperation with countries outside Europe as well.
Validation is currently available in the following states:
| Country | Code | Entry into force |
|---|---|---|
| Morocco | MA | 1 March 2015 |
| Republic of Moldova | MD | 1 November 2015 |
| Tunisia | TN | 1 December 2017 |
| Cambodia | KH | 1 March 2018 |
| Georgia | GE | 15 January 2024 |
| Lao People’s Democratic Republic | LA | 1 April 2025 |
Costa Rica signed a validation agreement in December 2024, but it has not yet entered into force.
Every European patent application is automatically deemed a validation request for all states with which a validation agreement is in force on the filing date. No separate formal request is needed for each country. The essential step is paying the validation fee within the required deadline.
The fee must generally be paid within six months of publication of the European search report, or for Euro-PCT applications, by the deadline for entry into the European phase — whichever is later. If the fee is not paid on time, the validation request is deemed withdrawn and the right to validation in that state is lost. In some cases, a two-month extension is available upon payment of a 50% surcharge.
Once validated, a European patent has the same effect as a national patent and is applied in accordance with national patent legislation. Infringement and invalidation actions are handled by national courts. While the patent is examined centrally at the EPO, enforcement remains a national matter.
Validation states may have their own translation requirements, publication rules, and renewal fees. Validation often requires translating the patent claims — and sometimes the entire patent publication — into the local language.
A single European patent application can cover a large number of countries without separate national examinations, eliminating the need to engage multiple local patent attorneys, pay separate examination fees, or manage parallel application processes. The patent is examined to EPO standards, considered among the highest in the world, and the system enables protection in rapidly growing markets outside Europe.
The EPO also emphasises the system’s development policy impact. Validation states benefit from technical cooperation, patent office training, IT system development, and the strengthening of local innovation ecosystems. In many countries, the system reduces the volume of national applications from foreign applicants and frees up local office resources for domestic innovation.
Validation also works in the context of international PCT applications, provided that the EPO is designated for a European patent, the validation state is designated for a national patent in the PCT application, and the validation agreement was in force on the international filing date.
EP validation applies to states outside the EPC, is based on bilateral agreements, and leads to national patent effects. The Unitary Patent applies to UPC member states within Europe and provides uniform protection across multiple EU countries. The UPC is a common patent court for Europe. These systems operate in parallel but on different legal bases.
New validation agreements are continuously being negotiated. The Costa Rica agreement demonstrates that the system is expanding further beyond Europe, reflecting the EPO’s ambition to strengthen its position as a global patent system rather than solely a European patent office.
Understanding the EP validation system enables informed decisions about international patent protection strategies. Professional guidance helps navigate complex validation requirements while optimising coverage across your target markets. For expert assistance with your EP validation strategy, contact our experienced patent professionals who can provide tailored advice for your specific patent portfolio needs.