A single patent application, in one language,[2] may be filed at the EPO in Munich,[3] at its branch in The Hague,[3][notes 2] at its sub-office in Berlin,[5] or at a national patent office of a Contracting State, if the national law of the State so permits.

[6] In September 1949, French Senator Henri Longchambon proposed to the Council of Europe the creation of a European Patent Office.

[7] His plan was however not found to be practicable by the Council's Committee of Experts in patent matters.

The signature of the Convention was the accomplishment of a decade-long discussion during which Kurt Haertel, considered by many as the father of the European Patent Organisation, and François Savignon played a decisive role.

However, the first patent applications were filed on 1 June 1978 (date fixed by the Administrative Council which held its first meeting on 19 October 1977).

The EPC is separate from the European Union (EU), and its membership is different; Switzerland, Liechtenstein, Turkey, Monaco, Iceland, Norway, North Macedonia, San Marino, Albania, Serbia, the United Kingdom, and Montenegro are party to the EPC but are not members of the EU.

[12][13] A diplomatic conference was held in November 2000 in Munich to revise the Convention, amongst other things to integrate in the EPC new developments in international law and to add a level of judicial review of the Boards of Appeal decisions.

"[26] As of October 2022, Bosnia and Herzegovina has an extension agreement with the EPO so that, in effect, this state can be designated in a European patent application.

First, discoveries, scientific theories, mathematical methods,[37] aesthetic creations,[38] schemes, rules and methods for performing mental acts, playing games or doing business, programs for computers[39] and presentations of information[40] are not regarded as inventions[41] and are excluded from patentability only to the extent that the invention relates to those areas as such.

The second set of exclusions, or exceptions, include: The Convention also includes provisions setting out filing requirements of European applications, the procedure up to grant, the opposition procedure and other aspects relating to the prosecution of patent applications under the Convention.

"[50] All Contracting States are considered designated upon filing of a European patent application.

Simultaneously to the opposition, a European patent may be the subject of litigation at a national level (for example an infringement dispute).

[56] This means that the European patent is granted and confers rights in all its designated Contracting States at the date of mention of the grant, whether or not a prescribed translation is filed with a national patent office later on (though the right may later be deemed never to have existed in any particular State if a translation is not subsequently filed in time, as described below).

A translation of a granted European patent must be filed in some EPC Contracting States to avoid loss of right.

[58] In other Contracting States, no translation needs to be filed, for example in Ireland if the European patent is in English.

In those Contracting States where the London Agreement is in force the requirement to file a translation of the European patent has been entirely or partially waived.

[64] A "Protocol on the Interpretation of Article 69 EPC" provides further guidance, that claims are to be construed using a "fair" middle position, neither "strict, literal" nor as mere guidelines to considering the description and drawings, though of course even the protocol is subject to national interpretation.

[79] Twelve EPC Contracting States, namely Belgium, Cyprus, France, Greece, Ireland, Latvia,[80] Malta,[81] Monaco, Montenegro,[82] the Netherlands, San Marino,[83] and Slovenia, have "closed their national route".