Patent enforcement proceedings

Lawsuits and courts

What legal or administrative proceedings are available for enforcing patent rights against an infringer? Are there specialised courts in which a patent infringement lawsuit can or must be brought?

The general procedural rules in the Administration of Justice Act, together with certain provisions in the Patent Act, regulate the civil procedure for claims for patent infringements, invalidation and declaratory actions.

Proceedings for such claims are typically instigated at the Maritime and Commercial High Court, which serves as the first-instance patent court in Denmark. Verdicts from the Maritime and Commercial High Court can be appealed to the High Court of Eastern or Western Denmark or, in rare circumstances, to the Supreme Court.

The swiftest way to enforce a patent right against a potential infringer is by submitting a request for a preliminary injunction to the Maritime and Commercial High Court. Preliminary injunctions are, in essence, a patent owner’s primary remedy, as they function as an effective and fast way of stopping infringing acts. Once a preliminary injunction is granted, it must be followed up by main proceedings to confirm the preliminary injunction with a permanent injunction.

Trial format and timing

What is the format of a patent infringement trial?


Court proceedings are instigated when the plaintiff submits a writ of summons to the court. The court gives the defendant a certain period (as a starting point, two weeks, which is often extended to four weeks) to submit a statement of defence. Subsequently, the parties participate in a preparatory court meeting (often held via telephone) with the court to outline the process leading up to trial.

In patent cases, court-appointed experts often provide statements regarding information relating to questions of validity or infringement. Subsequent to these expert statements, the parties may, and normally do, exchange further pleadings with the court. Depending on the complexity of the case, the oral hearing usually takes place 12 to 24 months from the date on which the writ of summons was filed.

In Danish patent cases, the general principle of free evaluation of evidence applies. The plaintiff must provide evidence for its claims (eg, regarding the patent infringement or patent invalidity). The courts are thus relatively free of constraints in their evaluation of evidence and both documents, affidavits and oral testimonies are relied on. The courts will, however, only rely on the evidence submitted by the parties during the court case. If evidence is likely to be destroyed by one party, a procedure securing such evidence or parts thereof can be used on request from the other party or parties. Technical evidence may be produced by submitting technical literature but the actual technical evidence is produced by way of statements from court-appointed experts.

 At trial

As a general rule, two technical judges and one legally trained judge (the president) participate in court cases at the Maritime and Commercial High Court. In cases of a particular complexity or fundamental nature, two additional technical or legally trained judges may participate, if the Maritime and Commercial High Court decides so. Hence, a patent owner can expect both high-level technical and judicial expertise. Jury trials do not exist in patent litigation.

In patent cases, court-appointed experts usually provide statements regarding the validity or infringement questions at hand. Normally, these expert statements play a substantial role in the court’s adjudication of the case. Expert witnesses summoned by only one of the parties are generally not allowed to be heard, except in preliminary injunction cases. As of 1 July 2017, new rules regarding court-appointed experts, which among other things allow the possibility to produce declarations from experts appointed by each party, entered into force. These rules generally allow for experts to play an even bigger part in litigation.

Cross-examination of witnesses is permissible, although it is subject to certain limitations, as the opposing party can only ask questions within the scope of the questions asked on direct examination. If witnesses do not show up for trial the court may take coercive measures.

Proof requirements

What are the burdens of proof for establishing infringement, invalidity and unenforceability of a patent?

The courts consider evidence on its merits and there are generally no formal rules on evidentiary standards. Therefore, the courts can decide what emphasis they will place on evidence produced by the parties.

Generally, the burden of proof of a claim lies with the party submitting the claim in question, unless statutory provisions provide otherwise. With respect to patent infringement and damages claims, the aggrieved party holds the burden. In invalidity and unenforceability proceedings, the party who claims that the patent is invalid or unenforceable holds the burden. These parties must establish conclusive evidence supporting their claims. A mere probability or presumption of the justification of their claims is usually not sufficient to meet the burden of proof. However, in preliminary injunction cases, it is sufficient that the patent owner shows that it is probable that the fundamental requirements for the grant of a preliminary injunction are satisfied.

According to section 64a of the Patent Act, a presumption exists in relation to process patents where the subject matter is a process for obtaining a new product. In such a situation, an identical product will be presumed to be manufactured by use of the patented process.

Standing to sue

Who may sue for patent infringement? Under what conditions can an accused infringer bring a lawsuit to obtain a judicial ruling or declaration on the accusation?

The general rule is that anyone with sufficient legal interest in the proceedings can bring an action before the courts. In the case of an infringement, proceedings will almost always be instigated by the injured party, namely the patent owner.

An accused infringer may make a claim of non-infringement or invalidity of a patent.

Inducement, and contributory and multiple party infringement

To what extent can someone be liable for inducing or contributing to patent infringement? Can multiple parties be jointly liable for infringement if each practises only some of the elements of a patent claim, but together they practise all the elements?

According to the Patent Act, contributory infringements are prohibited as no one except the patent owner may, without consent, exploit the invention by making, offering for sale or using a product or method, subject to the patent or a product being obtained by a method of the patent. Consequently, parties can be held liable for inducing or contributing to patent infringement. This is no different in the case of multiple parties each performing some of the elements necessary for establishing infringement, if their practise together constitutes an infringement.

Joinder of multiple defendants

Can multiple parties be joined as defendants in the same lawsuit? If so, what are the requirements? Must all of the defendants be accused of infringing all of the same patents?

Multiple parties can be joined as defendants in one lawsuit.

The defendants can be accused of different types of infringements. For example, if one defendant has performed a patented method and another defendant has sold a product made from the patented method, they can still be sued in the same lawsuit.

The Administration of Justice Act further requires that certain procedural rules on venue and subject-matter jurisdiction are met in order to join defendants in one lawsuit.

Infringement by foreign activities

To what extent can activities that take place outside the jurisdiction support a charge of patent infringement?

Principally, a party can only be liable if the patent infringement is taking place in Denmark. Foreign activities having an effect in Denmark may, however, be subject to patent infringement here. Indirect product protection means that the import and sale of a product in Denmark, which has been manufactured in a foreign country according to a method, which is patented in Denmark, but not in the foreign country, can be prohibited.

Infringement by equivalents

To what extent can ‘equivalents’ of the claimed subject matter be shown to infringe?

According to section 39 of the Patent Act, the extent of the protection conferred by a patent shall be determined by the claims. For the interpretation of the claims, the description may serve as a guideline. Hence, section 39 implements article 69 of the European Patent Convention (EPC) and prevailing Danish law is also in agreement with article 1 and 2 of the Protocol on the Interpretation of article 69 of the EPC, which forms an integral part of the EPC.

Despite the absence of a codified literal implementation of article 1 and of the mentioned protocol in the Patent Act, case law from the Danish Supreme Court confirms the principle of non-literal equivalents in Denmark. Consequently, a party can be held liable for patent infringement even though the infringing device, process, etc, does not fall within the literal scope of claims, if it is equivalent to the claimed invention.

As regards to what extent this doctrine can be claimed, the Danish courts follow the ‘mainstream’ European approach in positioning themselves between the two extremes formed by the German and English courts. However, these diverging approaches often lead to the same result in particular cases.

Discovery of evidence

What mechanisms are available for obtaining evidence from an opponent, from third parties or from outside the country for proving infringement, damages or invalidity?

The courts in Denmark may under certain conditions order preservation of evidence or discovery of specific documents.

The courts can assist with preserving evidence outside the scope of trial. A request must be filed with the relevant court of law being the district where the evidence is located. The court decides whether it is appropriate to preserve evidence. A case on preservation of the evidence does not need to be followed up by a trial if neither the plaintiff nor defendant initiates such proceedings.

A party may request that an opposing party or a third party must disclose specific documents which are at such party’s disposal. A request for disclosure must be specific and concern documents of relevance to the matter. Furthermore, a request must contain information on the facts that the requested documents shall serve as proof of as well as the reasons on which the requesting party basis the request. A failure to comply with a request for disclosure can be met by adverse inference.

Owing to a judicial opt-out, Denmark is not bound by Regulation No 1206/2001 on cooperation between the courts of the EU Member States in the taking of evidence in civil or commercial matters. Discovery of evidence between Denmark and other countries is regulated by the Hague Evidence Convention.

Litigation timetable

What is the typical timetable for a patent infringement lawsuit in the trial and appellate courts?

Danish courts can jointly rule on issues of validity and infringement. Generally, it takes approximately 12 to 24 months to obtain a first-instance decision in normal court cases, whereas it takes approximately six to nine months in preliminary injunction cases.

All aspects of the first-instance judgment may be part of an appeal (eg, questions or issues regarding matters of law and evidence). An appeal case before the High Courts of Eastern or Western Denmark normally takes nine to 18 months.

However, the above is dependent on the complexity of the case.

Litigation costs

What is the typical range of costs of a patent infringement lawsuit before trial, during trial and for an appeal? Are contingency fees permitted?

The cost of litigation depends on the complexity of the case. A first-instance case will cost approximately 500,000 Danish kroner for simple cases and between 2 million kroner and 4 million kroner for more complex (pharmaceutical) cases.

Preliminary injunction cases typically incur costs of 500,000 kroner for simple cases and 3 million kroner for more complex (pharmaceutical) cases.

Court appeals

What avenues of appeal are available following an adverse decision in a patent infringement lawsuit? Is new evidence allowed at the appellate stage?

The Danish legal system is based on the ‘two-instance principle’, which means that either party generally has the option of appealing the decision of one court to a higher instance.

A first-instance judgment from the Maritime and Commercial High Court can be appealed to the High Courts of Eastern or Western Denmark or, under very special circumstances, the Supreme Court.

All aspects of the first-instance judgment may be part of the appeal (such as, questions or issues regarding matters of law and evidence).

New evidence is allowed at the appellate stage and must generally be submitted in the notice of appeal or respondent’s notice.

Competition considerations

To what extent can enforcement of a patent expose the patent owner to liability for a competition violation, unfair competition, or a business-related tort?

The patent owner’s refusal to grant a licence or inappropriate enforcement activities to protect the patent may, in exceptional circumstances, constitute an abuse of dominance in violation of competition law.

Alternative dispute resolution

To what extent are alternative dispute resolution techniques available to resolve patent disputes?

Parties involved in a patent dispute can – as an alternative to litigation in court – settle the case by arbitration or mediation. The Danish courts offer court-based mediation, but there is no specialised arbitration system for patent disputes in Denmark.

Law stated date

Correct on

Give the date on which the information above is accurate.

12 March 2021.