Please note that certain English pages of the website - like this one - have not yet been updated compared to the pages available on the same subject in Dutch and French.

The updating of these pages is in progress .

It is therefore recommended that readers contact the Intellectual Property Office to verify the information they need is still topical, or that they seek independent professional advice before acting on the basis of the content of this website.

If you want to protect your invention in multiple European countries, it is better to request a European patent than to request a patent in each of these countries. Patent protection can be obtained in the 35 countries which are members of the European Patent Convention (hereinafter referred to as the "EPC") by filing once, via a single procedure. The European Patent Convention was updated in 2000. The “new” version of the European Patent Convention applies to European patent requests filed after 13 December 2007. However, patents issued before 13 December 2007 and European patent requests filed before this date as well as patents issued on the basis of these requests are subject to the 1973 version of the European Patent Convention. This European procedure is certainly more complex and longer than the Belgian procedure, due to the required patentability conditions, but it also leads to a more solid patent.

Those who seek a European patent generally designate all of the member countries of the European Patent Convention. During the procedure, the request can sometimes be withdrawn for certain countries and the patent limited to one or more countries.

A European patent delivered for a series of countries provides the same rights in the countries concerned as a national patent. The European patent consists of a number of national protection certificates. The patent is subject to national rules regarding the extension and transfer of patent protection, the licence, the implementation of rights, etc. A European patent can thus have a different weight according to the country in which it is applied.

There are 5 phases in the European procedure:

  1. Filing the patent request;
  2. The formal review of the patent request and the search for prior art. The full request and the search report are then published;
  3. If the applicant would like to continue with the procedure, the basic conditions of the patent are reviewed. Reviewers verify whether the patentability conditions are met, i.e. novelty, inventive character, industrial application and legality of the invention. The patent is then issued and published, or the request is rejected;
  4. After issuance of the patent, a third party may file an opposition;
  5. Finally, the decision to issue or reject a patent may be subject to appeal before the European Patent Office.

For more information, see the website of the European Patent Office (EPO).

Filing a European patent request

Where and how?

You can file a European patent request by submitting a form to a European Patent Office (EPO) located in Munich, the Hague or Berlin. This form can be sent by post, fax, in person or filled out online. You can also submit it to the Office for Intellectual Property in Brussels. 

This form is explained in detail on the EPO website.

Addresses and opening hours of the EPO.

Notice on the filing of European patent applications and international applications. (PDF, 231.51 KB)

You may also be represented by a patent attorney.

Content of the European patent request

It is important to fill out the request form correctly. A filing date is only given if certain data is provided. This date is used to determine the invention's novelty, and therefore to prioritise between different patent requests. Belgian patents as well as European patents are based on the "first to file" principle, which means that the first to file a patent request will be the patent holder, even if he is not the first to have invented the concerned invention.

The patent request must contain the following information:

  • A request for a European patent;
  • The applicant’s identification information;
  • A description of the invention:
    the invention must be described in a sufficiently clear and complete way in the patent request that a specialist in the same technical field could re-create the invention;
  • One or more claims:
    these claims describe the object for which patent protection is requested. Even if the description and potential drawings could be used to help interpret the claims, it is only the claims which determine the extension of the patent protection. If these claims are too restrictive, the patent which is accorded will be restrictive and you will not be able to change it later. Poorly described claims could thus lead to a very limited patent. We recommend therefore that you receive assistance from a patent agent;
  • Any designs used to explain the description or the claims:
    these designs will be indispensable if they are necessary for understanding the invention;
  • A summary which is used to communicate information on the patent to third parties;
  • Where applicable, the license authorization given to a representative (accredited patent agent, attorney, employee etc.).

A certain amount of the data mentioned above may be provided at a later date. However, proof of the European patent request, the applicant’s identifying information and the description of the invention or a reference to a request filed earlier are required in order for a filing date to be attributed. This date is used to determine the invention's novelty, and therefore to prioritise between different patent requests.

Language of the request

A European patent request may be filed in any language, but a translation in German, English or French must be provided within two months of filing. The claims must then be translated in German, English and French before final publication.

For a European patent to be protected in Belgium, a translation in one of the national languages (French, Dutch or German) must be provided. So, if a European patent was issued in English, a translation must be submitted to the Belgian Office for Intellectual Property within three months of publication of the patent issuance announcement.

If Belgium ratifies the London Protocol, this rule will no longer be applied and a patent issued in English will no longer need to be translated in one of our national languages. Translations of claims in French and German, filed at the EPO, will suffice for the patent to take effect in Belgium.

The translations which are currently required cost a great deal of money.


To obtain and maintain a European patent in effect, a certain number of taxes must be paid. For example, a filing tax must be paid within one month of filing the request. More information on patent taxes.

Formal review, search for prior art and publication of the request

Formal review

To obtain a filing date, a certain number of formal requirements must be met. The filing department of the European Patent Office checks to see whether the following data has been provided: the request for a European patent, the applicant’s identifying information and a description of the invention or a reference to a previously filed request. If the request meets these conditions, a filing date is provided.

Unless a priority right is invoked, this date is required to determine the novelty of the invention as well as to determine the order of filed requests. The patent life of 20 years is also calculated using this filing date. Issuance of a filing date does not ensure final issuance of a patent.

Next, the filing department verifies whether the required taxes have been paid and whether the other formalities have been carried out. If need be, an extension is granted to give the applicant time to complete the file. Patent requests are completed once the applicant completes any missing parts of his file before the end of the extension period.

Search for prior art

At the same time as the formal review, a search for prior art is carried out by the research division of the EPO. The resulting research report is sent to the patent applicant along with a written opinion which is non-binding in regard to the patentability conditions.

Publication of the request

As soon as possible after the end of the 18 month period following the filing date, the full request and research report are published in the EPO Bulletin. The file is now accessible by the general public.

Review of merits, issuance and publication of the patent

Review of merits

After publication of the research report, the applicant has six months to request a review of merits, or an examination of the patentability conditions of the invention. If the applicant does not do so (for example, because the research report clearly indicates that the invention is not novel), the patent request is considered withdrawn.

The review division of the EPO then checks whether the patentability conditions are met. They verify the novelty, inventive character, possibility of industrial application and legality of the invention; they also check whether there is a potential application of exclusion from the scope of patentability or a sufficiently clear and complete invention description.

Issuance and publication of the patent

If all conditions are met, taxes are paid and translations provided, the EPO issues the patent. The European patent enters into effect on the date it is mentioned in the EPO Bulletin. The patent is only valid as of this date, even if the applicant received provisional protection before this date.

The patent is published in its entirety in the EPO Bulletin and is accessible online.

For a European patent to take effect in Belgium, the translation requirements must be met.

4. Opposition

Within 9 months of publication of the patent issuance notice in the European Patent Bulletin, any interested party may file an opposition against the European patent delivered. This opposition must be based on grounds specified by law, in particular the fact that the patent does not meet the conditions of patentability, the description of the invention is not sufficiently clear, or whenever the issued patent offers wider protection than originally requested.

The EPO opposition division will examine the reasons for the opposition and will decide to revoke, maintain or modify the patent.

After the above mentioned period of 9 months opposition against the European patent is only possible at the competent national courts of each member state separately.

5. Appeal

All decisions made by the filing, research, review or opposition divisions of the EPO may be subject to appeal before the EPO Appeal Chamber within two months of their publication.

All Appeal Chamber decisions may also be subject to appeal before the Appeal Court, which ensures that all European Patent Convention rules are applied uniformly.

Last update
19 December 2019