As a multinational court, the UPC draws on a set of rules on the language of proceedings. These rules are designed to allow the parties and the court to communicate in the most flexible and balanced way possible, considering the essential interests of the parties and the principles of speed, efficiency, and cost-effectiveness.

To facilitate the understanding of the decisions, the following article outlines the basic structure of the language rules and summarizes lessons learnt from the existing case law on the language of proceedings. In the UPC’s first year of operation, these rules have led to the following distribution (Source: UPC):

For a detailed description of UPC language rules, see our article Language Regime and Translation Requirements under the UPC.

I. Why is the language choice relevant?

• The Court drafts all decisions and orders in the language of the proceedings. 
• Parties must submit all pleadings and documents in the language of proceedings. The Court may waive translation of annexes upon request if appropriate. 
• Patent applications, typically annexed to the statement of claim, must be translated unless the Court grants an exception. 
• The language of proceedings generally applies to oral hearings. The Court may order interpreters, either on its own or at a party's request. With the Court's consent parties can also appoint their own interpreters at their expense.

II. Basic approach for determining the language of proceedings

The UPC's language regime combines jurisdictional language and party choice: 

• The Central Division always uses the language of the patent in dispute. 
• Local Divisions follow more complex rules. Generally, the language is the official language of the contracting member state where the Local Division is located, one of the 24 official EU languages. This language applies to statements of claim in infringement proceedings and, exceptionally, revocation actions brought before the Local Division.
  
  Two scenarios allow multiple language options for Local Divisions: 
  • When a state has multiple official languages, as in Belgium (Dutch, French, and German). 
  • When contracting member states permit one or more European Patent Office languages, in addition to national languages. A current list of languages is available on the Court's website. In general, it is the official language(s) plus English. (Language of Proceedings | Unified Patent Court). 
• Regional Divisions follow the same language rules as Local Divisions, based on the official language of the Contracting State. Participating states can designate other EU languages. The Nordic-Baltic Regional Division (Sweden, Estonia, Latvia, and Lithuania) uses English. 
• The plaintiff chooses the language at the time of filing if multiple languages are available. The Court cannot change the language without parties' consent, except in certain infringement cases. 
• The Court of Appeal (CoA) typically uses the same language as the first instance but may use the patent language or another official language if agreed upon by the parties and with the Court's consent.

III. How to change the language of proceedings

The language of proceedings changes under the following circumstances: 

• When the legal dispute is transferred to another Division. 
• When there is a change in the patent-in-suit. 
• Initiated by parties to the proceedings: 
  • By mutual agreement of the parties, requiring an application by one of the parties until the end of the written procedure. If the Court rejects the request, the parties may jointly request to refer the case to the Central Division, which must be granted. 
  • If only one party wishes to change the language to the language of the patent, while the other party prefers to retain the chosen language, the Court decides. The Central rule of law that the Court must apply is Art. 49(5) UPCA. The interpretation of this provision is a central part of the case law in this area. The President of the Court of First Instance has authority, with the decision appealable to the CoA.

IV. Lessons learnt from the UPC’s decisions on languages

1. Local Division Dusseldorf (and CoA)

Curio Bioscience Inc. v. 10x Genomics, Inc.

The so far most intense battle over the language of proceedings occurred in the case of Curio Bioscience Inc. v. 10x Genomics, Inc., escalating to the appellate Court. On April 17, 2024, the Court of Appeal (CoA) overturned the Local Division Düsseldorf's decision from February 27, 2024, establishing interpretative principles for Article 49(5) UPCA.

In the first instance before the Local Division Düsseldorf, Curio Bioscience (the defendant) requested a change in the language of proceedings from German to English, the language of the patent. The Court denied the application. The request was based on Article 49(5) UPCA, which allows the President of the Court of First Instance to decide, in the interest of fairness and considering all relevant circumstances—including the parties' views and, particularly, the defendant’s—that the language of the patent should be used as the language of proceedings.

Curio Bioscience argued: 

• Both parties are U.S. companies, and the technology in question is in English. 
• The costs for necessary translations would disproportionately disadvantage them, as Curio Bioscience is a small or medium-sized enterprise (SME) significantly smaller than the plaintiff. 
• Using English as the language of proceedings would enable the Court of Appeal to use this language if needed.

10x Genomics responded: 

• The request lacked merit and evidence. 
• Curio Bioscience’s claim of being an SME was unproven, and the company operated globally, including in Germany, where German is widely used. 
• Curio Bioscience's representative was admitted to the German Bar, and their law firm had an office in Munich.

The Local Division saw no reason to change the language of proceedings. The language is determined by the plaintiff, and Article 49(5) UPCA did not justify a change in this case. There was no sufficient evidence or special circumstances warranting a language change, nor was Curio Bioscience proven to be an SME. Both parties faced the same translation needs, and the mere convenience of English for judicial activities was insufficient to support the request.

On appeal, Curio Bioscience reiterated its arguments, and the CoA overturned the lower Court's order, granting Curio Bioscience’s request. The CoA emphasized that all relevant circumstances must be considered when deciding on a language change, particularly the positions of the parties. Key factors included the language of the technology and evidence, as well as the size and resources of the parties.

The Court highlighted that the interests of the defendant are especially important due to the strict procedural deadlines they face. It recognized Curio Bioscience's arguments, noting that English as the language of proceedings was appropriate given both companies are U.S. based, the technological documents are mainly in English, and Curio Bioscience is significantly smaller than 10x Genomics. The reasons for maintaining German, such as its prevalence in the EU and the representatives' language skills, were deemed less relevant.

The Court also pointed out that changing the language of proceedings at this stage would not cause undue delay, as Germany had designated English as a procedural language for the Local Division Düsseldorf, requiring only a translation of the decision.

In conclusion, the Local Division Düsseldorf issued the order in the interim proceedings in German but included a certified translation. The language change two weeks before the planned announcement of the order did not unnecessarily delay the proceedings.

Notably, in the same case, the language of the proceedings was also a matter of dispute with respect to interpretation. Although the plaintiff chose German and opposed the defendant's request for English, the plaintiff requested simultaneous interpretation into English, which the Court consistently rejected. The parties were, however, allowed to arrange for a simultaneous interpreter at their own expense.

In another case between the same parties, initially filed in German, the parties later agreed to use English as the language of proceedings.

Aarke AB v. SodaStream Industries Ltd.

In this earlier decision from January 2024, Local Division Dusseldorf had decided differently when interpreting Art. 49 (5) UPCA. Here, the applicant requesting the change of the language of proceedings from German to English was clearly and verifiably an SME, so the balance weighed in its favour. The Court emphasized that addressing the challenges faced by SMEs in enforcing and defending their patents is an essential objective of the UPCA. By balancing Court fees with reasonable contributions and providing targeted support measures, the UPCA ensures fair access to justice for SMEs.

2. Local Division Munich

Amgen Inc. v. Sanofi-Aventis

In an interesting order dated 3 November 2023, the language of the proceedings was changed, whereby the Court's approach can be interpreted as meaning that the Local Division Munich prefers English as the language of the proceedings.

The defendant's representative suggested changing the language of proceedings from German to English, as the patent in suit was granted in English. The plaintiff's representative stated that the plaintiff favored a language that would make the work most manageable for the members of the panel. If this was to be English, the plaintiff would agree to a corresponding change of language, provided this did not cause any delay, and offered to submit the application in English translation. The members of the panel were in favor of the change. With the consent of all parties, the language of the proceedings was changed from German to English.

Meril v. Edwards

Edwards, the plaintiff, requested simultaneous interpretation from German to English, despite initiating proceedings in German. The Court denied the request, noting that organized interpretation was unnecessary and that Edwards, a U.S. company, could have initially chosen English. The patent was granted in English, and German-speaking judges were already assigned. Nevertheless, the Court allowed the parties to hire their own interpreter at their expense.

3. Local Division Hague

Plant-e Knowledge B.V., Plant-e B.V. v. Arkyne Technologies S.L.

In October 2023, the Court granted Arkyne Technologies S.L.'s request to change the language of the proceedings from Dutch to English, the language of the patent. Despite objections, the Court justified the change based on both parties' knowledge of English and prior use of the language. In particular, the Court noted that a proceeding in Dutch would have imposed significant and unnecessary translation costs on Arkyne, which is a small Spanish company.

4. Local Division Mannheim

Advanced Bionics v. MED-EL

In April 2024, after the CoA's decision in Curio Bioscience Inc. v. 10x Genomics, the Court examined Art. 49(5) UPCA and rejected the request to change the language of the proceedings. The Court considered proportionality, flexibility, fairness, and equity, noting that two defendants were in German-speaking countries and no significant financial imbalance or prejudice from using German was demonstrated.

5. Central Division Paris

CEAD v. BEGO

The language of the proceedings was German. The applicants, claiming that the German language skills of their key personnel were insufficient, requested simultaneous interpretation into Dutch or alternatively into English for the oral proceedings. The (German-speaking) Judge Maximilian Haedicke found that an interpreter was necessary for active participation on the basis of Article 51(2) UPCA, but refused to provide an interpreter at the Court's expense. The provision of an interpreter is at the discretion of the applicant and is at the expense of the applicant.

6. Local Division Hamburg

Tandem Diabetes Care v. Roche Diabetes Care

On July 25, 2024, the Court issued an order in the proceedings before the Local Division Hamburg, changing the language of the proceedings from German to English, the language of the patent. The applicants, Tandem Diabetes Care Inc. (et al.), supported this change, citing English's widespread use in the relevant technology field and as the corporate language of the involved international companies. Roche opposed the change, preferring to maintain German. The court found the application admissible and, after weighing the interests of both parties and considering the recent decision of the Court of Appeal in Curio Bioscience v. 10x Genomics, concluded that the balance of interests was equal. According to the Court, if the balance of interests is equal—here, both parties being international companies operating worldwide—the position of the defendant is decisive. Consequently, the court prioritized the defendants' position, noting that English would not disadvantage Roche, an international company accustomed to conducting business in English.

Conclusion

The choice of the language of the proceedings is crucial for the parties, as it affects written and oral communications with the court. Considerations for the choice include the language skills of the parties’ representatives (in-house and outside counsel), and the cost of translation and interpretation. The plaintiff's ability to choose the language offers potential savings and better communication, while the defendant is burdened with inconvenient procedural language and tight deadlines. The relevant case law is therefore important. Trends show: 

• The Court's divisions handle procedural language choices pragmatically and flexibly. Timely and clear communication to the Court can achieve much, especially if the parties agree. 
• In disputes, the language of proceedings is likely to change if the defendant is an SME or significantly smaller than the plaintiff. SMEs must demonstrate financial disadvantage to succeed. 
• The courts allow interpreters on request without issue but tend to transfer the costs to the parties, especially if they have deliberately chosen a language that requires translation.