European Patent Convention (EPC) Member States

European Patent Convention and European Patent Organisation

The European Patent Convention (EPC) is a multilateral international treaty signed in Munich on 5 October 1973 and in force since 7 October 1977. It established the European Patent Organisation and its executive arm, the European Patent Office (EPO).

Through the EPC system, applicants can obtain protection in multiple jurisdictions via a single European patent application. Once granted, a European patent becomes a bundle of national patents in the designated countries.

As of today, the system covers:

• 39 EPC member states
• 1 extension state
• 6 validation states

Since 1 June 2023, the Unitary Patent system also provides uniform protection across participating EU countries.

Validation and Extension System

European patent protection can go beyond EPC member states through:

• Extension: applies to countries with extension agreements
• Validation: applies to countries with broader bilateral agreements

Both require designation and payment of additional fees during prosecution.

A. EPC Member States — 39 Countries

B. Extension States — 1 Country

Extension states allow European patents to be extended to non-EPC countries through specific agreements with the EPO.

C. Validation States — 6 Countries

Validation states recognize European patents based on validation agreements with the EPO.

Note: Costa Rica signed a validation agreement with the EPO in December 2024. It has not yet entered into force.

Why This List Matters

Understanding the scope of the European patent system is essential when planning filing strategies, validation routes and cost structures. The distinction between EPC member states, extension states and validation states directly affects:

• Geographic coverage
• Validation requirements
• Translation obligations
• Renewal costs

Source: European Patent Office (EPO)
Last updated: March 2026