In Belgium, inventions can be protected through patents and supplementary protection certificates (SPCs). Trade secrets, although not intellectual property rights in the strict sense, are also widely used to protect non‑patented inventions.

Patents are based on statutory law, with three types of patent protections available in Belgium:

• national patents – on a national law level, patent rights are organised by Book XI of the Belgian Code of Economic Law (CEL);
• European patents – Belgium is a party to the European Patent Convention (EPC) and European patents are available and widely used; and
• unitary patents – with the entry into force of the EU Regulation No 1257/2012 implementing enhanced co-operation in the area of the creation of unitary patent protection and with the ratification by Belgium of the Agreement on a Unitary Patent Court, unitary patents may also be obtained and enforced in Belgium since 1 June 2023.

SPCs are governed by Regulation (EC) No 469/2009 concerning the supplementary protection certificate for medicinal products. This Regulation is complemented by Title 2 of Book XI of the Belgian Code of Economic Law (see 1.6 Further Protection After Lapse of the Maximum Term).

Patents

There are several routes to obtaining the grant of a patent in Belgium.

• The national route – a patent application is filed with the Belgian Office for Intellectual Property. No substantive examination of the patentability requirements is carried out, and a Belgian patent is automatically granted 18 months after the filing date. However, upon payment of a fee, the European Patent Office (EPO) will draft a search report with a written opinion on the patentability of the invention. A Belgian patent enters into force on the day on which it is made available to the public (ie, the grant day).
• The European route – Belgium is a party to the European Patent Convention (EPC), and a European Patent designating Belgium can be obtained by filing a patent application with the EPO. The EPO first conducts a formal examination (including verification of the fee payment, etc) and then issues a prior-art search report together with a written opinion on the patentability of the invention. Unlike for a Belgian national patent, the EPO carries out a full substantive examination of the patentability requirements. The procedure is contradictory and the applicant has the right to respond to any objection raised by the EPO, including by amending the patent application or by submitting arguments to address the issues raised. If the patentability is eventually confirmed, the EPO will publish its intention to grant. After payment of the relevant fees and the filing of any required translations, the European patent will be granted and published in the European Patent Bulletin. The European patent designating Belgium will then confer the same rights as a Belgian national patent.
• The unitary patent – the pre-grant phase is the same as for a European patent and the patent is granted by the EPO under the rules of the EPC. Once the European patent is granted, the patent proprietor must request unitary effect no later than one month after the mention of the grant of the European patent is published in the European Patent Bulletin, in order to obtain a “European patent with unitary effect”. The unitary effect provides uniform protection in all participating EU member states (currently 18, including Belgium).
• The international route – Belgium is a member of the Patent Cooperation Treaty (PCT), under which an international patent application can be filed to seek protection for an invention in multiple countries simultaneously. For Belgium, an international patent application must be filed at the EPO, which can ultimately lead to the grant of a European patent valid for Belgium.

Supplementary Protection Certificate

To obtain an SPC for a medicinal product (including the “paediatric” extension), an application form must be filed with the Belgian Office for Intellectual Property in one of the national languages. The application must contain, among other things, a request for the grant of an SPC; a copy of the marketing authorisation (MA) issued in Belgium; and additional information if the Belgian MA was granted after another MA in the European Union. Once the Belgian Office for Intellectual Property has confirmed that all the formal requirements are met, the certificate is issued and will enter into force on the day of expiry of the basic patent.

Trade Secrets

Trade secrets are not subject to any grant procedure and there is no formal application process. Protection instead depends on the implementation of reasonable measures to keep the information secret. No exclusive rights are conferred and the protection allows the trade secrets holder to act against unlawful acts (ie, the unlawful acquisition, use or disclosure of the trade secrets), provided that reasonable secrecy protection measures have been adopted and can be demonstrated.

Applicants are not legally obliged to be represented to initiate grant proceedings before the Belgian Office for Intellectual Property, even though this is almost systematically the case in practice. Belgian patents are automatically granted within approximately 18 months from the date of their application (see 1.2 Grant Procedure).

The costs associated with obtaining a national patent in Belgium can vary depending on several factors, including the complexity of the invention and the time needed to draft the patent application, the services of the patent attorney or agent, and any additional fees that may apply during the patent application process. Average costs for obtaining grant in Belgium, including patent attorney fees, range between EUR7,000 and EUR12,000.

Before the EPO, the overall timing from application to grant will largely depend on a number of various factors (eg, the complexity of the invention, the extent of examination required, the challenges and objections raised by the examiner, etc) and usually lasts between three and five years. Average costs to grant, up to validation in Belgium, may vary greatly and usually range between EUR10,000 and EUR20,000 (including patent attorney fees). Patent applicants do not need to be represented for the filing of a European patent application but any natural or legal person not having their residence or principal place of business in an EPC contracting state will need to be represented in all proceedings established by the EPC.

The term of protection for Belgian national patents, European patents and unitary patents is 20 years as from the filing date of the application. To maintain the patent in force, taxes need to be paid annually.

Patent term extensions of up to five years can be obtained via supplementary protection certificates (SPCs) for certain medicinal and plant protection products. The paediatric extension may extend the lifetime of an SPC granted for a medicinal product for an additional six months.

The protection of trade secrets is not limited in time and lasts for as long as the information is kept secret.

A patent confers exclusive rights to its owner, meaning that the patent holder has the right to exclude others from exploiting the invention in Belgium if done without its express consent (ie, the right to prohibit the use, making, offering, placing on the market, importing or stocking a patented product for that purpose; to prohibit the use of a patented process or to offer its use within the Belgian territory if the third party knows or should have known that the use is prohibited; and to prohibit the offering, placing on the market, using or importing or holding for these purposes of a product obtained directly by a patented process in Belgium).

Accordingly, a patent owner has the following rights in Belgium.

• Take legal action against any third party that infringes its patented invention. This may involve seeking damages, injunctive relief, and other corrective measures before the Belgian courts.
• License the patented invention, on an exclusive or non-exclusive basis, and authorise its use under certain conditions (including financial).
• Assign the patent to another party, allowing the latter to take over the ownership of the patent rights.
• Pledge a patent and grant an usufruct.
• Abandon a patent.

A patent owner has the obligation:

• to pay maintenance fees (annual fees need to be paid to maintain the patent in force); and
• under certain conditions, to grant a compulsory licence (see 2.2 Third-Party Remedies to Remove the Effects of Intellectual Property).

As mentioned in 1.4 Term of Each Intellectual Property Right, after their maximum term has lapsed and under certain conditions, the term of certain patents for medicinal and plant protection products may be extended for up to five years via supplementary protection certificates, and for an additional six months for certain medicinal products through the paediatric extension.

The protection granted by an SPC extends only to the product covered by the first marketing authorisation for that product as a medicinal product (regardless of its therapeutic indication), and only within the scope of protection conferred by the basic patent, for any medicinal use of that product authorised before expiry of the SPC.

The extension of the protection granted by an SPC aims to compensate the loss of exclusivity during the long regulatory approval process required to put a medicinal product on the market. The paediatric extension aims at fostering R&D investments in the development of medicinal products designed for children.

In the Belgian national route, third parties have no right to intervene in the grant proceedings.

In the European route, during the examination phase and after the publication of the European patent application, third parties may submit observations to the EPO on the patentability of the invention to which the application relates. These observations become part of the file and are communicated to the applicant, who is given an opportunity to comment on and challenge them.

In the national route, Belgian patents are granted automatically (there is no possibility of refusal and therefore no remedies are available).

In the European route, if the EPO refuses to grant a European patent, the applicant may file an appeal with the EPO Boards of Appeal, which act as the final instance in the grant procedure. The appeal must be filed in writing within two months of notification of the contested decision.

The Boards of Appeal may dismiss the appeal or, alternatively, correct the decision, or remit the case to the competent department for further prosecution.

Failure to pay the annual fees results in the expiry of the patent and the rights conferred by the patent will lapse.

In Belgium, there is a six‑month grace period starting from the last day on which the annuity should have been paid, subject to payment of an additional tax. If the annual fee is not paid within this grace period, the patent is forfeited.

A restoration procedure is, however, available before the Belgian Office for Intellectual Property under certain conditions. If restoration is granted, the legal consequences of the failure to pay the annual fees are deemed not to have occurred, and the patent is treated as if it had never ceased to have effect.

In Belgium, after grant of a national patent, the patent owner may still amend the patent either pursuant to a court decision in invalidity proceedings resulting in partial invalidity, or by filing an ex parte request for a partial waiver.

Before the EPO, a patentee may file an ex parte request for the limitation or revocation of its European patent, in order either to limit the granted claims or to revoke the patent in its entirety for all designated states. The request may be filed at any time after grant, including after the conclusion of opposition proceedings.

Civil Proceedings on the Merits

Belgian law provides for regular and accelerated infringement proceedings on the merits, in which a set of remedies are available to the patent holder (see 6. Remedies). The main differences between both proceedings are the timeframe and the possibility to obtain compensation for the damage resulting from the infringement.

Accelerated proceedings enable the initiation of a procedure to obtain injunctive relief on the merits, within a faster timeframe. There is no urgency requirement, but no damages may be claimed. Any damage compensation will require the subsequent launch of a regular proceeding on the merits. The president of the Brussels Enterprise Court is competent and the duration to obtain a first-instance decision usually ranges between six and ten months.

In regular proceedings, the patentee may claim damages and is entitled to full compensation if the infringement is confirmed (the entire damage must be compensated, no more and no less, and punitive damages are not allowed). The duration to obtain a first-instance decision before the Brussels Enterprise Court usually ranges between 18 and 24 months.

Preliminary Injunction (PI) Proceedings

Both inter partes and ex parte PI proceedings are available under Belgian law to obtain interim injunctions pending a decision on the merits. The PI judge may order a variety of measures that can limit, stop, or avoid the damage resulting from the alleged infringement (including an injunction to stop the commercialisation and/or the advertising of the product, a product recall, or under certain circumstances the seizure of the allegedly infringing goods). Injunctive relief may be sought on an ex parte basis in cases of exceptional urgency and provided that the measures sought are “absolutely necessary” (see 2.7 Interim Injunctions).

Criminal Proceedings

Criminal proceedings are available in Belgium under certain conditions. To constitute a criminal offence, the infringement must take place within a commercial context and be committed with malicious or fraudulent intent. Criminal proceedings are rather exceptional in patent cases.

Customs

Customs seizures are organised by Regulation (EU) No 608/2013 and enable customs authorities to block the entry into the territory of the European Union of goods “suspected of infringing an IP right”. If there are reasonable indications that there is infringement, the customs authorities may suspend the release or detain such goods at the border. Once blocked, the goods may either be destroyed (absent opposition of the owner) or, if the conditions for destruction are not fulfilled, the patent or SPC owner must initiate judicial proceedings to establish the alleged infringement. The customs authorities may intervene either on their own initiative (unlikely in patent/SPC cases) or at the request of the owner of the patent or SPC right.

Several remedies are available to third parties to remove the effects of patent rights in Belgium.

Nullity Action of a Belgian Patent or of the Belgian Part of an EP Patent

In Belgium, granted patents (a Belgian patent or the Belgian part of an EP patent) enjoy a rebuttable presumption of validity but may be invalidated in whole or in part by the competent court if invalidity is established. Nullity actions may be brought before the Brussels Enterprise Court by any party having a legitimate interest, which requires demonstrating that the claimant may obtain a material or moral benefit likely to change and improve its legal position. This is usually the case where the parties are active in the same field, are competitors, or when the claimant is accused of infringing the patent at issue or faces a risk of such an infringement claim. Invalidity grounds are exhaustively listed in the patent law and must be substantiated by the claimant seeking to invalidate the patent. If the patent is invalidated, the final and binding nullity decision will eventually be recorded in the Belgian patent registry.

For the Belgian part of an EP patent, nullity actions can be brought before the Brussels Enterprise Court in parallel with an opposition proceeding before the EPO. The Belgian nullity proceedings are not automatically stayed pending the resolution of the opposition. A stay may be requested but it is discretionary and, in practice, is often refused.

A Belgian court recently took into account the conduct of a patent holder in the European patent grant procedure, during which amendments were made to the EP application that originally contained claims identical to those of the granted Belgian patent. The court held that substantial amendments made to the EP application during the grant procedure, combined with statements made by the patent holder’s lawyer during the Belgian nullity proceeding, amounted to an extrajudicial admission of the invalidity of the Belgian patent as granted. The Belgian part of the EP patent was therefore revoked.

If not opted out, the Belgian part of an EP patent can be invalidated either before the Brussels Enterprise Court or the Unified Patent Court (UPC). A unitary patent may be revoked by the UPC.

Declaration of Non-Infringement Action (DNI)

A pre-emptive DNI can be filed in Belgium by anyone having an interest to act – ie, the action must prevent the violation of a right which is seriously threatened. The threat must be established by the claimant and must be real and not merely theoretical in the sense that it must cause a specific disturbance to the plaintiff. Receiving a cease-and-desist letter and/or having parallel infringement proceedings pending in other jurisdictions will usually suffice to establish the interest to act.

Compulsory Licence

Compulsory licences may be imposed on the patentee by the Belgian Minister of Economic Affairs following a rather complex administrative procedure laid down by law. The legal grounds for granting a compulsory licence are listed in the legislation and include non‑exploitation of the invention, dependency on another patented invention, and reasons of public health.

In Belgium, all patent disputes are handled by the Brussels Enterprise Court which has exclusive jurisdiction. Most judges have no technical background but this centralisation of patent cases allows a certain degree of specialisation of the competent judges. Proceedings will take place in either French or Dutch and, in some instances, strategic decisions will need to be made to bring the case before either the French or Dutch Brussels Enterprise Court.

Appellate proceedings are handled by the Brussels Court of Appeal.

In the third instance, the Belgian Supreme Court (Hof van Cassatie or Court de Cassation) is competent. This court does not rule on the merits and only assesses the correct application of the law in the decisions rendered on appeal.

For the Belgian part of the European patents that have not been opted-out, disputes may be brought either before the national courts (in this case the Brussels Enterprise Court), or the UPC. For unitary patents, the UPC is exclusively competent. The UPC has a local division in Brussels.

Belgian courts are not bound by decisions of the UPC or the EPO. However, Belgian case-law tends to follow the guiding principles of the EPO Enlarged Board of Appeal to promote a uniform application of European patent law (eg, the recent G2/21 decision on the use of post-published evidence to demonstrate inventive step). UPC case law is also expected to gradually influence Belgian case law.

There are no specialised bodies or organisations for the resolution of patent disputes in Belgium.

In Belgium, there is no formal requirement to send a formal demand or cease-and-desist letter prior to filing a lawsuit, although this is done in practice in most cases.

If the judge considers there is an opportunity to bring the parties closer together, and unless all parties object, the judge may order mediation at an early stage of the proceeding (ie, after having heard the parties at the introductory hearing, or at a postponement hearing set shortly thereafter, or at a hearing held within one month of the filing of the defendant’s first written submissions).

An exclusive licensee may, under certain conditions, initiate patent infringement proceedings, but only after the patent licence has been registered with the patent office, as this registration is required for the licence to be enforceable against third parties.

In Belgium, parties in patent disputes must be represented by lawyers, who have an exclusive right of representation. Since 1 April 2024, patent attorneys may intervene in patent disputes to provide written or oral explanations on factual matters, technical issues or patent law questions, without prejudice to the role of the lawyers, who remain in charge of the proceedings as dominus litis.

Interim injunctions are available under Belgian law, both inter partes and ex parte, with various measures available to limit, stop, or avoid the damage resulting from the alleged infringement. The president of the Brussels Enterprise Court has jurisdiction over both inter partes and ex parte preliminary injunctions (PI) proceedings. Inter partes PI proceedings typically take around two to four months, and first‑instance PI measures are enforceable notwithstanding any appeal. Ex parte decisions are usually obtained much more quickly, typically within a few days.

Obtaining a preliminary injunction requires establishing that:

• the matter is urgent;
• the patent right invoked is prima facie valid;
• there are indications of (imminent) patent infringement; and
• in some cases, the balance of interests favours the right-holder.

The judge will assess in concreto whether these conditions are met and will disregard arguments that go beyond the prima facie nature of PI proceedings.

European patents (EP patents) enjoy a strong presumption of prima facie validity in Belgium, and case law is relatively pro‑patentee: as a rule, a granted EP patent is deemed valid and enforceable unless and until it is revoked by a final decision of the EPO or a Belgian court. Even relatively weak patents therefore carry a risk of being successfully enforced through preliminary injunction proceedings. However, the PI judge must take into account all relevant facts and circumstances relied on by the parties when assessing prima facie validity, including, for example, foreign decisions on the validity of the national parts of the EP patent concerned.

The urgency requirement – that is, the need to show that irreparable harm will be suffered if immediate measures are not taken, or that the dispute on the merits cannot be resolved in time – is central in interim proceedings, and the specific circumstances of the case are crucial to this assessment. Belgian case law generally considers the urgency requirement to be met where a risk of patent infringement is established.

The urgency requirement is more stringent for obtaining ex parte interim injunctions. The patent holder must demonstrate exceptional urgency and show that the measures sought are “absolutely necessary”; that is, that there is extreme urgency, or that the nature of the measure requested requires a unilateral procedure to guarantee its effectiveness. This extreme‑urgency requirement is applied very strictly by the court and must remain exceptional.

Interim injunctions are limited in duration, and the right holder must initiate proceedings on the merits within a specified timeframe.

In Belgium, protective letters may be filed but they are not organised by law and the competent judge is under no obligation to take them into account. They are regularly used where a party fears being targeted by a descriptive seizure accompanied by effective seizure measures. The main purpose of such a letter is to ensure that the party is heard by the judge and to prompt an inter partes debate before the requested measures are granted, so that the targeted party can challenge them and avoid any element of surprise if they are granted.

The judge may make the grant of interim measures conditional on the provision of a bond, but this is not automatic.

Patent infringement proceedings are time‑barred five years after the date on which the infringement was committed. For damages, the claim for compensation is time‑barred five years from the day following the date on which the patentee or SPC owner became aware of the infringement, subject to a maximum limitation period of 20 years from the date on which the infringement was committed.

In a pending proceeding, a party may ask the judge to order the production of certain well-identified documents that contain the proof of a relevant fact useful for resolving the dispute. The production will only be ordered if there are “serious, precise and concordant presumptions of possession by the party of a document containing evidence of a relevant fact”.

The Belgian descriptive‑seizure procedure enables the collection of evidence of an alleged patent or SPC infringement. It may not, however, be used to collect information unrelated to the patent or SPC at issue, including information concerning alleged misappropriation of trade secrets.

Descriptive measures are obtained on unilateral request, either before or after infringement proceedings have begun, and are commonly granted in Belgium (most infringement cases are preceded by a saisie (seizure)). The timing to obtain a decision ranges between two to three days and one week.

The requirements are straightforward and the patent or SPC holder will need to demonstrate (i) that the patent invoked is prima facie valid, and (ii) that there are indications (not evidence, only a mere indication) that the patent has been infringed or that there is a threat of patent infringement. Indications of infringement are a matter of circumstances, that can be established by all legal means.

If the request is granted, the court appoints an expert who is authorised to carry out a surprise visit to the alleged infringer’s premises (or any other location in Belgium where evidence of the alleged infringement may be found) in order to collect information on the alleged infringement and its scope. The expert then files a confidential report describing its findings, and the patentee must bring infringement proceedings on the merits within a specified period; if they fail to do so, the measures granted are annulled and the right-holder may no longer rely on the report in court.

To initiate a lawsuit in Belgium, the claimant must set out a clear and plausible statement of the facts supporting the claim, together with the corresponding evidence. During the proceedings, the parties will exchange several rounds of written submissions and may supplement their pleadings with additional arguments and new evidence (proceedings are not front‑loaded). The initial claim may even be extended or amended, provided that any new claim is based on a fact or act mentioned in the original writ of summons. In this respect, case law has confirmed that merely referring to a patent in the writ of summons as part of the claimant’s portfolio, without alleging that it has been infringed, does not satisfy this requirement and does not allow the patentee to introduce a new infringement claim based on that patent in later submissions.

The Belgian legal system theoretically permits class actions in case of an alleged violation by an undertaking of the laws listed in Article XVII.37 of the CEL, which includes Book XI of the CEL that covers “Intellectual Property Rights and Trade Secrets”. Such class actions must be brought on behalf of a group of consumers or of small and medium-sized enterprises that have been harmed by the alleged violation. The claim must be filed by a group representative meeting certain conditions set by the CEL and the recourse to a class action must appear as more efficient than an ordinary law proceeding. The possibility to bring class actions seems rather limited in patent cases.

The owner of a patent may be restricted in asserting its rights against others based on the abuse-of-rights principle. As a general principle of Belgian law, a patent owner may not abuse its rights and cannot exercise them to obtain an advantage that is totally disproportionate to the prejudice caused to others. In certain circumstances, where the patent owner has several ways of exercising its right, it may not choose the option that is most harmful to others if not justified by a sufficient interest.

The exercise of an IP right, by a dominant undertaking, does not in itself constitute an abuse of dominant position (see CJEU 30 January 2020, Case C-307/18, EU:C:2020:52, Generics) but under specific circumstances an IP holder may be limited to assert its rights if the assertion qualifies as an abuse of dominant position (under competition law). In case of Standard Essential Patents, the refusal to grant a FRAND licence can, in certain circumstances, constitute an abuse of dominant position. FRAND case law is not developed in Belgium.

In one case, later overturned on appeal, the first‑instance judge held that the refusal to grant a licence constituted an abuse of economic dependence and ordered the grant of a non‑exclusive licence in Belgium under certain conditions. The appellate decision was subsequently quashed by the Supreme Court, which remitted the case to the appellate court, where the proceedings are still pending.

The principle of res judicata also applies: a claim that has been adjudicated on the merits cannot be litigated again.

The owner or usufructuary of a patent is entitled to bring an infringement action.

In the event of co‑ownership, and unless otherwise agreed, a co‑owner may bring an infringement action only with the consent of the other co‑owner(s) or, failing such consent, with the authorisation of the court.

In the event of a patent assignment, the assignee may initiate infringement proceedings, but only after the assignment has been registered in the patent register. Some case law considers that such registration is relevant only in relation to third‑party property rights in the patent as an asset, and should not prevent the patent holder from bringing infringement proceedings.

In the case of an exclusive licence, the licence must also be registered in the patent register in order to be enforceable against third parties. The exclusive licensee may bring an infringement action if, after formal notice to the patentee, the latter fails to do so. The same rule applies to compulsory licences.

Once the licence has been registered in the patent register, any licensee (whether exclusive or non‑exclusive) is entitled to intervene in infringement proceedings brought by the owner or usufructuary of the patent in order to obtain compensation for its own losses.

Under Belgian law there is a difference between direct and indirect infringement.

Direct Infringement

If committed on the Belgian territory without the patentee’s consent, a patent owner can prevent a third party from:

• manufacturing, offering, placing on the market or using any product covered by the patent, or importing or stocking such product for that purpose;
• using a process which is the subject matter of the patent or, if the third party knows or should have known that the use of the process is prohibited without the consent of the patent owner, offering its use on the Belgian territory; and
• offering, placing on the market, using or importing or holding for these purposes a product obtained directly by a process which is covered by the patent.

Direct infringement requires that all the features of the asserted patent claim are implemented in the infringing product or process (see 3.4 Scope of Protection for an Intellectual Property Right for the infringement by equivalence).

Indirect Infringement

The patent owner may also act against indirect infringement and prevent any third party, without its consent, from supplying within Belgian territory means for implementing the patented invention that relate to an essential element of that invention, provided the third party knows or ought to know that those means are suitable and intended for such implementation. This does not apply where such means are commonly available on the market, unless the third party induces the person to whom they are supplied to commit an infringing act.

Products obtained directly by a patented process benefit from the same protection as patented products. Belgian law expressly provides that “offering, placing on the market or using, or importing or possessing for the aforementioned purposes, the product obtained directly by the process covered by the patent” constitutes an act of infringement. Importing into Belgium a product obtained directly by a patented process therefore constitutes an infringing act and gives rise to a right of action in Belgium, even if the process was carried out overseas; the lawfulness of the manufacturing process abroad is irrelevant in this respect.

Belgian law also provides for a reversed burden of proof for process patents where the product obtained via the patented process is new and the alleged infringer is placing an identical product on the market. In such a case, the identical product is presumed to have been obtained through the patented process and is deemed infringing. To benefit from this mechanism, the patent holder must prove:

• that the product is new – the “novel” character of the product is not defined by law and Belgian case law is divided on this notion (some decisions consider it equivalent to the “novelty” requirement for patentability, while others treat it as a distinct concept); and
• that the products are identical – the identity requirement is not defined by law but is applied quite strictly by the courts, and must be assessed by reference to the products themselves, not the patented process.

The Belgian Supreme Court recently held that a commercial offer stating that a product is compatible with protocols covered by a process patent constitutes an infringing offer.

The scope of protection conferred by a patent is determined by the claims, while the description and drawings are used to interpret those claims. Belgian case law has consistently held that where the meaning of the claims is clear from reading the claims, no interpretation is required and recourse to the description is only necessary in cases of ambiguity. However, in decision G 1/24 of 18 June 2025, the EPO Enlarged Board of Appeal held that the description and drawings must always be taken into account when interpreting the claims, regardless of whether or not the claim wording appears ambiguous. This marks a departure from the traditional approach of the Belgian courts.

Patents should in principle be interpreted restrictively, with the willingness to understand the claims, and an interpretation that makes technical sense will be favoured over a nonsensical one.

The doctrine of equivalence is applied in Belgium, meaning that the scope of protection is determined both by the wording of the claims and by potential equivalents (subject to certain conditions ). The majority of Belgian case law follows the EPO’s “function-way-result” approach. To determine if there is infringement by equivalents, the court examines the (essential) feature in question as to if it:

• has substantially the same function;
• performs the function in substantially the same way; and
• leads to substantially the same result.

In light of UPC case law, including that of the Belgian local division, which applies several tests rather than relying solely on the “function‑way‑result” approach, it remains to be seen if and how this will affect Belgian case law.

Belgian case law generally recognises a defence based on prosecution history estoppel: a patent holder cannot rely, in infringement proceedings, on a scope of protection that contradicts limiting statements made during the grant procedure to distinguish the invention from the prior art. An alleged infringer may therefore contest infringement by equivalents by invoking the EPO prosecution file and any limitations made during prosecution.

In Belgium, the prior‑possession defence is available and expressly provided for by law. The alleged infringer must show that, in Belgium and in good faith, it used or possessed the patented invention before the filing or priority date. Prior possession must have given it full, practical knowledge of the invention sufficient to enable its use before that date. The prior use must be certain, unambiguous and must have occurred in Belgium. This defence is intuitu personae: only the legal entity that can prove it used or possessed the invention in good faith in Belgium may rely on this exception.

Belgian case law also recognises the Gillette-defence (also known as “Formstein defence”), which is a hybrid defence between invalidity and non-infringement that consists of claiming that the alleged infringer merely implements the state-of-the-art, or a non-inventive variant thereof. If confirmed, this defence will result in a lack of infringement or, alternatively, in the invalidity of the patents invoked since they would merely reflect the prior art.

The compulsory licence defence is also available, including where the exploitation of an invention is dependent on another patented invention, but this is seldom used and rather theoretical (see 2.2 Third-Party Remedies to Remove the Effects of Intellectual Property).

Patent exhaustion is also an available defence under Belgian law. The rights conferred by a patent do not extend to acts relating to a product carried out in Belgium after that patented product has been placed on the market in a member state of the EU by the patent owner or with its express consent.

Other exceptions to the rights conferred by a patent may be invoked as defences. These include, among others, the Belgian research exemption or “exemption for experimental use” which has recently been modified to align with the provisions of the UPC Agreement.

In the pharmaceutical field, the Bolar exemption permits the studies, tests and trials necessary to obtain regulatory approval in Belgium or the EU for biosimilar or generic medicinal products for human use. In addition, following the recent amendment of the Belgian research exemption regime, all acts carried out for the purpose of evaluating a medicine are regarded as acts done for experimental purposes and, therefore, do not constitute infringement (the so‑called “Bolar+” exemption).

Belgian courts have recently issued several decisions concerning the SPC manufacturing waiver for both export and stockpiling (the “Waiver”). This exception allows generic and biosimilar manufacturers, subject to certain conditions, to produce an active ingredient protected by an SPC for export outside the EU, or for stockpiling in Belgium for commercialisation immediately after SPC expiry. Recent case law tends to consider that the grant of a marketing authorisation in the country of export is not required in order to validly notify an SPC manufacturing waiver for export.

Patent disputes often involve technically complex issues, whereas Belgian judges typically do not have a technical background. In Belgian patent litigation, the court may appoint a judicial expert to provide a non‑binding opinion on specific technical questions to be decided. Such an opinion may cover various issues, including validity, infringement and the assessment of damages. Judicial experts are appointed at the judge’s discretion, either on their own initiative or at the request of a party. The parties are given an opportunity to comment on, and to challenge or endorse, the expert’s conclusions, which often increases the length and cost of the proceedings.

Any party to Belgian proceedings may also support its position with expert statements, as part of its burden to prove the facts it alleges.

In Belgium there is no separate procedure for construing the terms of the patent claims. Issues related to the validity of the patent, the construction of the claims and the infringement of a patent are handled within the same proceedings.

In Belgium there is no system through which the court may seek or receive third-party opinions (amicus brief).

In Belgium, the revocation/cancellation of a patent can be requested independently in a nullity procedure or through a counterclaim in the context of an infringement action.

The reasons to seek the nullity and revocation of a patent are:

• the subject matter of the invention is not patentable (excluded patentable subject-matter include discoveries, scientific theories and mathematical methods; aesthetic creations; plans, principles and methods for carrying out intellectual activities, games or economic activities, as well as computer programs; and presentations of information);
• the invention does not meet the patentability requirements of:
1. novelty;
2. inventive step; or
3. not being susceptible to industrial application;
• the patent does not contain a sufficiently clear and complete description of the invention to enable a person skilled in the art to carry out the invention;
• the claims contain added subject matter – ie, the claims are not covered by the content of the original patent application; and
• the patent holder was not entitled to the patent.

Where the validity of a patent is disputed for lack of inventive step, Belgian case law generally applies the EPO’s “problem–solution” approach, starting from the prior art that is closest to the invention in dispute. This may evolve in light of UPC case law, which accepts different approaches for assessing whether or not an invention involves an inventive step.

The claimant seeking to invalidate a patent in a Belgian proceeding must have a legitimate interest in doing so (ie, the claimant is entitled to expect a material or moral benefit likely to change and improve its legal position, which is usually the case when the parties are active in the same field or are competitors, or when the claimant is accused of infringing the patent at stake or there is a risk of patent infringement claim).

The UPC has jurisdiction over actions for revocation of patents and SPCs, and over counterclaims for revocation of patents and SPCs, in respect of European patents that have not been opted out and in respect of unitary patents. The EPC is the primary source of law governing patent validity before the UPC.

Partial revocation or cancellation of a patent is possible in Belgium if the grounds for invalidity affect the patent only in part (the partial revocation of a patent is usually invoked as a defence in the context of infringement actions). In such case, the patent is declared partially invalid from the start and the claims will be amended, as will be the description and drawings, where applicable.

In revocation or cancellation proceedings, either in the context of a nullity action or of a counterclaim seeking to invalidate the patent, the amendment of the scope of the patent is possible, provided that this does not lead to an extension of the scope of protection. The amended claims must satisfy all cumulative patentability requirements. Where applicable the claims will be amended with the description and drawings.

There is no bifurcation system in Belgium and revocation or cancellation and infringement claims are heard together, in a single proceeding before the Brussels Enterprise Court.

Before the UPC, the central division is in principle competent for revocation cases concerning unitary patents and European patents which have not been opted-out. However, the system is more complex and, in case an infringement action is pending, the revocation claim will need to be filed before the same local division in charge of the infringement case. The local division will then have the choice to proceed with both infringement and revocation claims, or go for bifurcation and transfer the revocation action to the competent Central Division, or transfer the whole case to the Central Division (if all the parties agree).

As explained in 2.1 Actions Available Against Infringement and 2.10 Mechanisms to Obtain Evidence and Information, in Belgium there are mainly two specific procedures for intellectual property rights, which are, respectively:

• the Belgian descriptive-seizure proceeding that enables the collection of evidence of an alleged patent/SPC infringement – descriptive measures can be obtained on an ex parte basis (to guarantee a surprise effect), in a matter of days (between two to three days and one week), at any time before or after the launch of an infringement proceeding; and
• an accelerated infringement proceeding on the merits (action en cessation) – though not limited exclusively to intellectual property rights proceedings, this procedure enables to obtain injunctive relief on the merits, within an accelerated timeframe (six to ten months) but without the possibility to claim compensation (this will require the filing of a subsequent procedure on the merits).

In Belgium, all patent disputes are handled by the Brussels Enterprise Court, which has exclusive jurisdiction. The seat of the court will be constituted exclusively by legal judges (no technical judges are involved and disputes are not determined by a jury). As noted in 2.3 Courts With Jurisdiction, this centralisation allows for a specialisation of the judges even though they have no technical background.

Patent disputes may be settled by the parties at any stage of the proceedings, provided they agree on the terms of a settlement. The agreement may be submitted to the court seised of the dispute so that the settlement can be recorded, thereby bringing the proceedings to an end. The settlement agreement and the resulting judgment are, in principle, binding on the parties and not subject to appeal.

As explained in 2.5 Prerequisites to Filing a Lawsuit, unless all parties disagree, the judge may order the parties to engage in a confidential mediation in the early stages of the procedure. In case an agreement is reached, the mediation agreement will be submitted to the court by the parties, or by either of them, for homologation. The mediation agreement and resulting decision will then be binding on the parties and may not be appealed.

In Belgium, an infringement proceeding may be stayed pending resolution of an opposition proceeding before the EPO. This is not systematic and usually requires the agreement of all parties to the procedure.

Parallel revocation and infringement proceedings in other jurisdictions are unlikely to influence a pending infringement action before the Belgian courts, unless several foreign decisions have been rendered reaching the same conclusion.

Anti-suit injunctions are prohibited under Belgian law.

In Belgium, in case a patent or SPC is found to be infringed, the judge will order the persons liable for infringement to cease the infringement activities (permanent injunction).

In a regular infringement proceeding on the merits, the judge will, on request, also order the compensation of the patentee for all the damages resulting from the infringement. Punitive damages are not allowed and the rule is that the patent/SPC holder must be fully compensated for any damage sustained; ie, the patent/SPC holder must be restored to the same state as if the infringement had not occurred, nothing more, nothing less. In the event of bad faith, the judge may order the transfer of all or part of the profits made from the infringement to the patent/SPC holder.

In addition, the judge may order measures that are likely to contribute to stopping the infringement (both in ordinary and accelerated proceedings on the merits) and/or to compensating for the damage (only in ordinary proceedings on the merits). At the request of the party entitled to bring the infringement action, such measures may include:

• the recall of the infringing goods from the trade channels, the final withdrawal from trade channels or the destruction of the infringing goods, as well as, where appropriate, of the materials and tools used principally for their manufacturing;
• the order to provide the patentee/SPC holder with all the information it has on the origin and distribution networks of the infringing goods or services and to communicate all data relating thereto (subject to a proportionality assessment); and
• the publication or display of the decision, or of a summary thereof, in newspapers or in any other manner including on the infringer’s website, at the infringer’s expense.

Remedies can be enforced after the decision is served on the losing party and are usually granted with penalty payments as sanctions against non-compliant defendants.

In patent disputes, the prevailing defendant will, in principle, be entitled to recover the costs of the procedure, including:

• a statutory lump sum to cover its lawyers’ fees (based on the value of the dispute; see 8.3 Responsibility for Paying the Costs of Litigation);
• the technical adviser’s and expert’s fees (including patent attorney fees); and
• monetary compensation for any damages suffered if the defendant can prove that the patent/SPC owner committed a fault by initiating the infringement proceeding.

There is no strict objective liability, and under current case law the threshold for establishing fault is high, which in practice makes obtaining monetary compensation difficult. However, in light of more recent CJEU case law confirming that an objective liability regime is compatible with Directive 2004/48/EC on the enforcement of intellectual property rights, this position may evolve and could lead to a reassessment of the applicable Belgian liability standard.

In Belgium, the same remedies apply as listed under 6.1 Remedies for the Patentee. There are some variations for trade secrets due to the different nature of this right, including in the corrective measures that may be ordered by the judge. As an example, the judge may order “depriving the infringing goods of their infringing quality”, and can prohibit the obtention, use or disclosure of trade secrets and order the prohibition to produce, offer, place on the market, use, import, export or stock for those purposes, of the infringing goods.

In Belgium, the rule is that first-instance decisions are provisionally enforceable pending appeal, at the risk of the enforcing party. Unless otherwise provided in the court decision, injunctions will therefore be enforceable even if an appeal is lodged.

The opposite rule applies in nullity proceedings. If the patent is revoked (partially or totally) in the first instance or on appeal, the appeal or appeal to the Supreme Court will have suspensive effect.

There are no special provisions concerning the appellate procedure in patent or SPC disputes. The appeal is available to all parties to a procedure, and, for patent cases, must be brought before the Brussels Court of Appeal within one month of the service of the first-instance decision.

The appeal implies a full review of the facts of the case and is not limited to a legal review. The initial claim may even be extended or modified, and new evidence can be submitted.

In the third instance, as stated under 2.3 Courts With Jurisdiction, the Belgian Supreme Court is competent and does not rule on the merits of a case. Only a legal review will be carried out.

The costs that arise before filing a lawsuit vary from one case to another and are mainly caused by the intervention of the lawyers, patent attorneys, bailiff, and experts that will be working on the preparation of the case (including for assessing the merits of the case, analysing the patents/SPC and the products or processes at stake, collecting relevant evidence, engaging experts, and undertaking pre-litigation actions such as warning letters or protective letters, as well as drafting the writ of summons).

In Belgium, the court fees for commencing proceedings are statutory fees, the amount of which depends on the competent court. Before the Brussels Enterprise Court competent in patent and SPC matters (see 5.2 Decision-Makers), these fixed fees amount to EUR165 in the first instance. These fees will eventually be borne by the losing party and are payable after the receipt of the judicial decision.

The losing party is liable for the costs of litigation, including court fees, expenses, technical experts’ fees (such as patent attorneys’ fees) and lawyers’ fees. However, the prevailing party’s lawyers’ fees are recoverable only via a statutory lump sum known as a “procedural indemnity”, which is set by law and mainly depends on the amount in dispute. In practice, the procedural indemnity is largely insufficient to cover the actual legal fees, and the successful party cannot recover its lawyers’ fees beyond this indemnity.

Alternative dispute resolution (ADR) methods, including mediation and arbitration, are generally voluntary and all the parties must agree to settling their intellectual property dispute through these mechanisms.

Belgian law explicitly provides that parties may settle patent disputes relating to ownership, validity or infringement, as well as to patent licences (other than compulsory licences) through arbitration. Arbitration procedures are confidential and faster, but will be more costly.

The traditional judicial litigation route is, however, more commonly chosen for patent and SPC disputes, since Belgium enjoys a well-established legal system, with specialised patent judges that contribute to the trust placed in the judicial litigation route.

Under Belgian law, the assignment of patents must be done in writing to be valid.

To be enforceable against third parties, the assignment must be notified to and registered with the Belgian Office for Intellectual Property. However, even before registration, the assignment is enforceable against third parties who acquire rights after the date of the assignment and who were aware of the assignment when they acquired those rights.

In case of co-ownership, each co-owner has a pre-emption right for a period of three months as from the notification of the proposed assignment, unless otherwise provided for in a co-ownership agreement.

The price paid for the transfer of ownership may be a lump sum or be proportionate to the exploitation revenues by the assignee during a certain term. A patent assignment may be partial – eg, restricted to a specific application of the patent.

Patent applications may also be assigned, in which case the same rules apply.

As mentioned in 10.1 Requirements or Restrictions for Assignment of Intellectual Property Rights, Belgian law requires a written instrument for an assignment to be valid, and the patent office must be notified and the assignment registered for it to be enforceable against third parties. Notification can easily be made using the forms made available by the Belgian Federal Public Service (FPS) Economy.

Belgian law requires patent licences (both exclusive and non‑exclusive) to be made in writing in order to be valid.

To be enforceable against third parties, the licence must then be notified to and registered with the Belgian Office for Intellectual Property. Such registration is required to enable an exclusive licensee to enforce the licensed patents in the event of infringement, and to enable both exclusive and non‑exclusive licensees to intervene in infringement proceedings brought by the patent owner in order to obtain compensation for their own losses (see 3.1 Necessary Parties to an Action for Infringement).

In the event of patent co-ownership, a co-owner may only grant a licence with the agreement of the other co-owner(s) or, in the absence of such agreement, with the authorisation of the court.

A licence may be exclusive or non-exclusive, partial or total, and subject to payments or not (royalties, lump sum, etc).

Patent applications may also be licensed. Under Belgian law, the owner of a patent application may claim reasonable compensation for the exploitation of the invention during the period between the filing of the application and the grant of the patent.

As mentioned in 10.3 Requirements or Restrictions to License an Intellectual Property Right, Belgian law requires a written instrument for the licence to be valid (this is a validity requirement), and the patent office must be notified and the patent licence registered to be opposable to third parties. The notification can be easily done via forms made available by the Belgian Federal Public Service (FPS) Economy.