In a judgment of 25 June 2026 (case no. 2025/FQ/16, registry no. 2026/4792), the 43rd chamber (family) of the Brussels Court of Appeal ordered the rectification of a birth certificate for a dual Italian-Portuguese national born in Belgium. The court held that two birth certificates assigning two different names to the same individual were irreconcilable with the universal and unique character of a person's name. The judgment, obtained by Altea, is relevant to any person whose official identity differs from one country to another as a result of conflicting rules on the attribution of names at birth.
The background : Federico A. was born in Belgium in 1990, to an Italian father and a Portuguese mother. His Belgian birth certificate, drawn up shortly after his birth on the father's declaration alone, recorded him solely under his father's surname “D.M.”. Weeks later, both parents jointly registered the birth at the consular section of the Portuguese embassy in Brussels. That consular record assigned him the compound name “A.D.M.”, combining both parents’ surnames in accordance with Portuguese law as it then stood.
Federico A. grew up in Belgium, attended the European School under the name A.D.M., and then settled in Portugal in 2022. His diplomas, his Portuguese passport, and his marriage certificate from Portugal (2024) all bear the name A.D.M. When he returned to Belgium in 2025 and sought to re-register with a Belgian municipality, the authorities identified a discrepancy between the Belgian records and his Portuguese identity document. That discrepancy blocked the issuance of a new Belgian identity card.
On 8 July 2025, Federico A. filed a petition for birth certificate rectification under article 35 of the former Civil Code. The family court of the French-speaking court of first instance of Brussels had dismissed the application on 3 October 2025, finding no ground to prefer the Portuguese identity over the one recorded in the Belgian birth certificate.
The Court of Appeal reversed that decision. It first recalled that the family court's jurisdiction to rectify civil status records is not limited to clerical errors and extends to errors arising from the misapplication of foreign law. It then observed that Federico A. was born before the entry into force of the Belgian Code of Private International Law (1 October 2004) and that the attribution of his name at birth was governed by his effective nationality, by reference to the former article 3 of the Civil Code. The court also invoked the Hague Convention of 12 April 1930 on conflicts of nationality laws, whose principles apply to relations between non-contracting states and were subsequently incorporated into article 3 of the Belgian Code of Private International Law. Where a person holds dual nationality not including Belgian nationality, the applicable law is that of the state with which the person has the closest ties.
The court found that the link to Portuguese law had been expressly chosen by both parents within weeks of the birth, with no equivalent step taken before the Italian authorities. That choice had shaped Federico A.'s entire life: his schooling, diplomas, marriage and passport. The court referred to the judgments of the Court of Justice of the European Union in Garcia Avello v. Belgian State of 2 October 2003 (case C-148/02) and Grunkin-Paul of 14 October 2008 (case C-353/06) to illustrate the practical inconveniences of a patronymic discrepancy. It also cited the European Court of Human Rights judgment in Kismoun v. France of 5 December 2013, which requires states to take account of the hardship caused by the existence of two distinct identities in two different countries.
The scope of this judgment is not confined to situations involving two European Union member states. The legal basis relied upon by the Court of Appeal rests on the rules of Belgian private international law and on the general principles governing conflicts of laws in civil status matters. These rules apply whenever a birth in Belgium involves parents of different nationalities, regardless of which nationalities those are. Any child born in Belgium to parents from countries with diverging rules on the attribution of names may face an identical situation.
The procedure for birth certificate rectification before the family court, provided for by article 35 of the former Civil Code, represents a workable remedy in such cases.
Céline Verbrouck
Attorney at the Brussels Bar
Specialised in immigration law, nationality law and international family law
www.altea.be
+32 2 894 45 70