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?

In Germany, patent rights can be enforced in legal proceedings before the district courts, either by way of preliminary injunction proceedings or a main proceeding on the merits. In order to ensure that there is a group of judges with a frequent workload of patent cases and thus adequate competence, patent infringement matters are concentrated by law to specific patent chambers of 12 district courts: Munich I, Nuremberg, Mannheim, Frankfurt, Saarbrücken, Erfurt, Leipzig, Magdeburg, Düsseldorf, Braunschweig, Berlin and Hamburg.

In general, each federal state has at least one patent infringement court; however, some federal states share courts.

The most prominent – and busy – courts are Düsseldorf, Mannheim, Munich I, and Hamburg.

Trial format and timing

What is the format of a patent infringement trial?

German patent infringement trials are front-loaded. The proceedings on the merits commence therefore with the filing of a statement of complaint with the court. The statement of complaint contains the requests and a detailed account of the infringement. The statement of complaint is then formally served on the defendant, usually with a summons to an early oral hearing, which may also be a case management conference in which only the deadline regime is set and the motions are made. Some courts use this hearing to try to negotiate a settlement between the parties.

Before the main oral hearing, each party usually files two briefs:

  • the plaintiff – a statement of complaint and a rejoinder; and
  • the defendant – a statement of reply and a counter rejoinder.


Owing to this detailed preparation, cases are often tried in one main oral hearing before the first-instance decision is rendered.

The disputed issues are decided by (non-technical) judges (one presiding judge and two assessors).

Documents, affidavits and live testimony are used as evidence to prove or rebut the infringement. Further, expert witnesses are an important means of evidence. However, if the court deems that an expert witness opinion is necessary to hand down a judgment, it will appoint its own expert witness. Such expert witnesses are the most common means of providing evidence in patent infringement cases. Expert witnesses appointed or submitted by the parties have less importance. The court will carefully consider the expert opinion rendered by its appointed expert witness. However, it is not bound by this opinion and may deviate from it.

Depending on the court, it takes approximately seven to 15 months from the service of the statement of complaint on the defendant until a first-instance decision is handed down by the court.

Proof requirements

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

In general, each party must set out and prove the actual features of the legal rule favourable to the respective party. The plaintiff must prove the conditions on which its claims are based. The alleged infringer must prove the facts that deny the claims. The specific distribution and extent of the burden of proof in the course of the proceedings depends on the submissions in the specific case. The more detailed the submission; the more detailed must be the response.

This means that it is first the plaintiff’s duty to substantiate all facts relevant to the decision (such as the right to sue, infringement acts and the features of the patent claim) and all facts should be presented precisely and, if possible, with indication of the source of knowledge.

It is then the responsibility of the defendant to respond to this submission conclusively and, in the case of dispute, to provide proof for his or her allegations. This includes also any defence he or she may rely on (eg, invalidity of the patent).

Only if specific facts submitted by one party are substantially disputed by the other party, does the burden of proof rest on the party submitting these facts to provide sufficient proof for their assertions, either by way of documents, witnesses or experts.

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 patent owner and a licensee (exclusive and non-exclusive) may sue for patent infringement. With respect to the latter, the extent of the right to sue and the respective remedies obviously depend on the scope of the licence.

An accused infringer may bring an action for declaratory of non-infringement.

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?

Someone can be liable to contributing to an infringement under the conditions of section 10 of the German Patent Act:

The patent shall further have the effect that any third party shall be prohibited, in the absence of the consent of the proprietor of the patent, from supplying or offering to supply, within the territorial scope of this Act, persons other than those entitled to exploit the patented invention with means relating to an essential element of the invention for use within the territorial scope of this Act if the third party knows or if it is obvious from the circumstances that those means are suitable and intended for using that invention.


It is therefore in particular necessary that the alleged infringer provides means relating to an essential element of the invention. A means refers to an element of the invention if it is capable of interacting functionally with it in the realisation of the protected inventive idea. This is, for example, the case by offering and delivering a device element that can be combined with other elements to form the patented overall combination.

In general, multiple parties will be jointly liable.


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?

Yes, multiple parties can be joined as defendants in the same lawsuit. The parties must be accused of infringing the same patent and the same infringing embodiment or methods.

Infringement by foreign activities

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

According to the case law of the Federal Court of Justice (BGH), a person who enables a third party to use the protected object through his or her own conduct in breach of duty is also liable for a patent infringement (see BGH case ref. X ZR 120/15). These principles also apply to foreign activities contributing to a patent infringement committed in Germany. For example, where a person, in applying a procedure, takes advantage of the fact that certain steps of the protected procedure are carried out by a third party (abroad), that third party may also be liable for patent infringement; and a foreign person (company), who supplies products to a foreign customer is involved in an act of domestic use if it knows that the customer will supply the products to Germany (BGH, case ref. X ZR 69/13 – Audiosignalcodierung).

Infringement by equivalents

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

German patent law applies the doctrine of equivalents. The requirements are as follows:

  • the accused product must solve the problem of the invention with objectively equal means;
  • the skilled person must be able – based on his or her specialist knowledge – to find the technical solution of the altered version of the accused product as objectively equal; and
  • the skilled person must determine that the altered accused product is equivalent to the objective (literal) solution of the patent.
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 concept of discovery is unknown in German procedural rules.

However, in order to obtain evidence, the initiation of inspection proceedings pursuant to section 140(c) of the Patent Act is available. The inspection can also be enforced with a preliminary injunction. The requirements for obtaining a preliminary injunction for an inspection are low. It is sufficient merely to demonstrate a probability of patent infringement.

Litigation timetable

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

The litigation timetable depends very much on the concrete venue.

Depending on the court, it takes approximately seven to 15 months from the service of the statement of complaint on the defendant until a first-instance decision is handed down by the court. Where evidence is taken, the procedure may take an additional six to 12 months.

As the court sets a strict deadline regime, there is little scope for expediting the process.

The appeal stage (Higher District Court) will typically take another eight to 12 months.

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?

This depends on the disputed value of the court costs. In general, the total cost of an average case should be calculated at a minimum of €70,000 to €100,000; the costs for an appeal can be assumed to be a little lower. However, the total costs depend very much on the complexity of the case, the number of parties and the number of IP rights to be asserted.

Contingency fees are (currently) not permitted.

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?

An adverse (or partly adverse) decision on the merits before the District Court can be appealed to the Higher District Court, which will be a full legal review of the case. Therefore, generally, the appeals court has to base their review upon the facts and evidence determined by the first instance court. However, under very narrow circumstance new facts or evidence is allowed:

  • if there are doubts in relation to correctness and completeness of the facts determined by the first instance court based upon concrete indications; and
  • if explicitly allowed by law, in particular by section 531 sec. II of German code of civil procedure, if:
    • the court has apparently overlooked one aspect or inaccurately determined it as not relevant;
    • the new facts were not considered due to a procedural error; and
    • the delayed submission of the new fact is not due to negligence.
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?

According to established case law of the Federal Court of Justice, an unjustified warning based upon an industrial property right may infringe the right of the alleged infringer to the established and practised business (business-related tort).

Enforcing a standard essential patent only towards specific infringers may under circumstances be relevant under competition law. 

Alternative dispute resolution

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

Some of the patent infringement courts particularly foresee mediation processes for suitable cases; the Munich court, for example, proposes an internal court mediation to use the time between the dates of the oral hearings to achieve an amicable, appropriate and interest-based solution. The preliminary view of the case given by the chamber in the early first appointment often gives the parties reason to try mediation.

Besides that, it is possible to resolve patent matters by out-of-court mediation or arbitration proceedings.

Law stated date

Correct on

Give the date on which the information above is accurate.

18 March 2020.