Extension states

Extension states are European countries that are (or were formerly) not party to the EPC but to which European patents can be extended under co-operation and "extension" agreements signed with the European Patent Organisation.

To obtain patent protection in these countries, applicants have to submit a request and pay an extension fee within a set time limit. Once extended to these countries, their European patent applications and patents basically have the same effect there as national ones.

A complete list of extension states with which the EPO has signed extension agreements is available on the EPO website.

Related topics

Request for extension/validation with effect in extension/validation states