Serving court documents on Chinese defendants remains a challenge in UPC litigation. A recent decision by the Milan Local Division of the EPO points to possible solutions.

Background: A Cross-Border Service Challenge

In December 2025, the Milan Local Division of the Unified Patent Court (UPC) issued a notable decision (Case UPC_CFI_766/2024) addressing the difficulties of serving court documents on companies based in China. The case involved a patent infringement claim by Cardo Systems against two defendants, one in Hong Kong and one in mainland China. While the Hong Kong-based defendant was ultimately served on a second attempt, service on the Shenzhen (PR China)-based company failed twice due to objections raised by Chinese authorities. This situation highlighted the procedural hurdles and international complexities when delivering UPC legal documents abroad under the Hague Service Convention.

The Hague Service Convention and UPC Rules of Procedure

When serving defendants outside the EU (and outside the UPC’s member states), the UPC relies on the Hague Service Convention as the primary mechanism for cross-border notification. The UPC’s Rules of Procedure explicitly integrate the Hague Convention’s framework, ensuring a uniform approach to service across all participating states. In fact, the Milan court emphasized that Article 15(2) of the Hague Service Convention applies fully in the UPC system, regardless of any additional national requirements, because the UPC has a uniform service regime and all member states have effectively adopted the Convention’s rules by agreeing to the UPC Rules. In practice, this means that if a document needs to be served in a non-UPC country like China, the serving party must follow Hague Convention procedures (e.g. through the designated Central Authority) before resorting to any alternative methods.

Political and Formalistic Obstacles: The China Dilemma

In the Milan case, the Chinese Central Authority twice refused to execute service on the Shenzhen defendant for an unusual reason: the court papers referred to the first defendant’s address as “Hong Kong” instead of “Hong Kong, China”. This demand – essentially a political/semantic issue – created a serious obstacle to serving the lawsuit. The UPC court noted that such a refusal was based on a purely formalistic ground, since the first defendant in Hong Kong had already been successfully served (making the address wording issue moot). More importantly, the court held that foreign authorities have no right to demand changes to the content of judicial documents. Quoting a prior UPC decision, the Milan judge stressed that “censorship of content based on political expediency has no place in the Hague Service Convention”, and it is not the role of a receiving state’s agency to “censor or edit the content of the document to be served”. How a claimant describes a defendant’s address is up to the claimant; a Central Authority cannot block service over terminology or political nuances. The Chinese authority’s insistence on the phrase “Hong Kong, China” was therefore deemed an improper basis to refuse service.

The Milan Court’s Solution: Valid Service Despite Refusal

Facing a “serious and final” refusal by China’s authorities to effect service, the Milan Local Division took a pragmatic approach. The court declared that the steps already undertaken by the claimant to serve the Chinese defendant – transmitting the documents via the Hague Convention process – were sufficient to constitute legally valid service, even though the defendant had not physically received the papers. Under the Hague Convention (Article 15) and UPC rules, once all reasonable formal attempts have been made and a foreign authority definitively rejects or fails to complete service, the court may proceed without further delay. The Milan decision confirmed that no additional attempts were necessary in this case, as requiring more tries or waiting longer would be futile.

Crucially, the court refused to alter or “water down” the content of the documents to satisfy the foreign authority, citing the independence and impartiality of the judiciary. Instead, the judge treated the Chinese authority’s non-cooperation as a breach of the Hague Convention obligations and moved forward by issuing an order to validate service. In the court’s words, “the steps already taken…constitute legally valid service. Otherwise, service would be impossible.”

Alternative Means: Notice by Publication on the UPC Website

To further safeguard the defendant’s due process rights despite the lack of formal service, the Milan Local Division employed an unconventional backup method: publication of a notice on the UPC’s website. The court ordered that a reference to its decision (including the party names and case number) be posted on the publicly accessible UPC website, effectively as a form of public notice. This way, even though official service through Chinese channels failed, the defendant could still become aware of the ongoing proceedings by seeing the announcement online. The court explicitly stated that formal service of the decision itself was unnecessary (and would have been doomed to fail for the same reasons) once this online publication was made. This approach — essentially service by public notification — is provided for in the UPC framework as a last resort when all formal avenues are blocked.

Practical Takeaways for UPC Litigation

• Plan for Delays and Obstacles: Serving defendants in non-EU countries like China can be fraught with unexpected hurdles. Be prepared for potential delays and formal objections (in this case, it took nearly a year of efforts and a court order to resolve service).
• Adhere to Hague Convention Formalities: Ensure full compliance with Hague Service Convention requirements (proper translations, forms, addresses, etc.) when serving abroad. Minor errors or deviations can prompt refusals, as seen with the “Hong Kong” nomenclature issue. While the UPC won’t require altering your documents to appease foreign authorities, anticipating local sensitivities (e.g. naming conventions) might save time.
• UPC Rules Require Exhaustion of Official Channels: The UPC will generally insist that you exhaust formal service methods under Hague (or applicable international channels) before seeking alternative means. Attempts to bypass official procedures (like direct email or local publication at the court) will not be approved “at this stage” unless convention routes truly fail.
• Courts Won’t Tolerate Unreasonable Refusal: If a foreign state’s authorities refuse service for improper reasons, the UPC is prepared to declare service effected regardless. In Milan, the judge treated the Chinese authority’s stance as contrary to the Convention and moved on. Practitioners can take comfort that good-faith attempts to serve won’t be in vain due to politics or formalism.
• Alternative Service by Court Order: The Milan case demonstrates that the UPC can resort to alternative measures like publicizing the case on the court’s website when standard service is impossible. Lawyers should be aware that a defendant who evades service (or whose country obstructs it) may still be bound by proceedings that continue in their absence. For defendants outside Europe, it’s wise to monitor UPC publications and not rely on local authorities to forward documents.
• Looking Ahead: This decision fits neatly with the principles already developed by the Court of Appeal in CoA_69/2024, order of 9 July 2024. It signals that the UPC will strike a balance between respecting international service treaties and ensuring that litigation isn’t derailed by external roadblocks. In future cases involving non-EU parties, we can expect the UPC to take a similar pragmatic approach, upholding the integrity of its process while using creative solutions (like website notices) to give defendants a fair chance to respond.