The procedure for issuing a Belgian patent is relatively simple because it does not include a review of the conditions of patentability. The European Patent Office searches for prior art of the invention but the result of this research does not have an impact on the issuance of the patent. This research report is accompanied by a written opinion on the invention's patentability for the applicant’s informational purposes. If the patent’s validity is contested later on, a judge will make a decision on the case. For patent requests filed before 8 January 2009, it is still possible to obtain a "small patent" without carrying out research on prior art; this patent only has a maximum duration of 6 years.

A Belgian patent request is recommended if you only plan on using your invention within Belgium, even if this type of protection does not ensure the validity of your patent.

Belgian patents offer other advantages. You can use the Belgian patent as a “first filing” which gives you a priority right to file a patent request in other countries within 12 months.

Filing a patent request

Where and how?

To request a patent, you must fill out a request form (PDF, 67.98 Kb) at the Office for Intellectual Property (click here (PDF, 70.21 Kb) for the form in German).

The request form may always be filed in person, sent by fax (in this case, an original version of the request must arrive at the OPRI within 14 days) or by post. Concerning request forms filed by post or in person, see the "contact" page.

You can be represented by an expert.

Content of the Belgian 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 patent addressed to the relevant Minister;
  • 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, a notice on the geographical origin of the biological material used to develop the invention, if this material is known;
  • 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 patent request, the applicant’s identification information and the description of the invention as well as any and all claims 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 request for a Belgian patent may be filed in French, Dutch or German. No other translation is required for the validity of the request in Belgium.

Payment of application fees

Proof of payment of the application fee must arrive at the OPRI within one month of the patent request application.

Attribution of a filing date

The date on which the OPRI received the patent request is noted in a statement which serves as a filing date, as long as the request includes the following information:

  • A declaration confirming the request for a patent addressed to the Minister;
  • The applicant’s identification information;
  • A description of the invention;
  • One or more claims.

Unless a priority right is applied, this date is used to determine the invention’s novelty and to prioritise the order of patent applications. This date is also the starting date for the duration of patent protection. Issuance of a filing date does not ensure final issuance of a patent.

Search for prior art

The applicant must pay taxes for the search for novelty carried out by the OPRI within 18 months of filing (or the priority date if a priority right is invoked. This research is carried out by the European Patent Office which prepares a research report and provisional written opinion on the patentability conditions.

This search for prior art was optional for patent requests filed before 8 January 2009. Unless this research was requested, only a "small patent" with a maximum duration of 6 years was issued.

The search for prior art and the written opinion are not binding and provide no definitive guarantee as to the patent's validity. Even if the invention is not new or if another condition is not met, a Belgian patent may still be issued for this invention. Even if the patent’s validity is contested in court, the judge's decision is not restricted by these documents. The definitive validity of the patent will only be decided on a case-by-case basis via legal proceedings. However, the research report and the written opinion have a useful informative role and allow the patent applicant to withdraw or adapt a request.

This is an important difference between Belgian and European patents. The latter implies that the European Patent Office will verify whether the conditions of patentability were met and, if not, refuse to issue a patent.

Issuance and publication of the patent

Once all administrative formalities have been accomplished and all taxes paid, the patent is issued via Ministerial Decree as soon as possible after the end of the 18 month period after the filing date (or the priority date if a priority right is invoked). The applicant may request that the patent be issued more quickly if all conditions are met. These could be useful if the patent is threatened shortly after the patent request is filed, as the patent does not enter into effect before the date of issuance and publication.

A Belgian patent requires only that all formal obligations are met, including the payment of required taxes, and offers no guarantee that the patent's conditions of validity have been met. This is an important difference compared to European patents.

The patent is mentioned in an official register which can be accessed on the OPRI website. The full patent as well as the request files are also accessible on the OPRI site once the patent is issued. The OPRI also provides a concise publication of the essential characteristics of issued patents in the Invention Patents Manual.

The patent enters into effect once it is made available to the public (in principle, the day of its deliverance), or once it is published by the OPRI. Before this publication, the patent applicant still receives provisional protection of the invention.

Last update
9 August 2019