Carlos Garcia Avello v Belgian State.
Date: 2003-10-02
13.  Mr Garcia Avello, a Spanish national, and Ms I. Weber, a Belgian national, are resident in Belgium, where they married in 1986.  The two children born from their marriage, Esmeralda and Diego, who were born in 1988 and 1992 respectively, have dual Belgian and Spanish nationality.
21.  Article 17 EC confers the status of citizen of the Union on every person holding the nationality of a Member State (see, in particular, Case C-224/98   D'Hoop   [2002] ECR I-6191, paragraph 27).  Since Mr Garcia Avello's children possess the nationality of two Member States, they also enjoy that status.
22.  As the Court has ruled on several occasions (see,   inter alia  , Case C-413/99   Baumbast and R   [2002] ECR I-7091, paragraph 82), citizenship of the Union is destined to be the fundamental status of nationals of the Member States.
23.  That status enables nationals of the Member States who find themselves in the same situation to enjoy within the scope   ratione materiae   of the EC Treaty the same treatment in law irrespective of their nationality, subject to such exceptions as are expressly provided for (see, in particular, Case C-184/99   Grzelczyk   [2001] ECR I-6193, paragraph 31, and   D'Hoop  , cited above, paragraph 28).
24.  The situations falling within the scope   ratione materiae   of Community law include those involving the exercise of the fundamental freedoms guaranteed by the Treaty, in particular those involving the freedom to move and reside within the territory of the Member States, as conferred by Article 18 EC (Case C-274/96   Bickel and Franz   [1998] ECR I-7637, paragraphs 15 and 16,   Grzelczyk  , cited above, paragraph 33, and   D'Hoop  , paragraph 29).
25.  Although, as Community law stands at present, the rules governing a person's surname are matters coming within the competence of the Member States, the latter must none the less, when exercising that competence, comply with Community law (see, by way of analogy, Case C-336/94   Dafeki   [1997] ECR I-6761, paragraphs 16 to 20), in particular the Treaty provisions on the freedom of every citizen of the Union to move and reside in the territory of the Member States (see,   inter alia  , Case C-135/99   Elsen   [2000] ECR I-10409, paragraph 33).
26.  Citizenship of the Union, established by Article 17 EC, is not, however, intended to extend the scope   ratione materiae   of the Treaty also to internal situations which have no link with Community law (Joined Cases C-64/96 and C-65/96   Uecker and Jacquet   [1997] ECR I-3171, paragraph 23).
27.  Such a link with Community law does, however, exist in regard to persons in a situation such as that of the children of Mr Garcia Avello, who are nationals of one Member State lawfully resident in the territory of another Member State.
28.  That conclusion cannot be invalidated by the fact that the children involved in the main proceedings also have the nationality of the Member State in which they have been resident since their birth and which, according to the authorities of that State, is by virtue of that fact the only nationality recognised by the latter.  It is not permissible for a Member State to restrict the effects of the grant of the nationality of another Member State by imposing an additional condition for recognition of that nationality with a view to the exercise of the fundamental freedoms provided for in the Treaty (see in particular, to that effect, Case C-369/90   Micheletti and Others   [1992] ECR I-4239, paragraph 10).  Furthermore, Article 3 of the Hague Convention, on which the Kingdom of Belgium relies in recognising only the nationality of the forum where there are several nationalities, one of which is Belgian, does not impose an obligation but simply provides an option for the contracting parties to give priority to that nationality over any other.
31.  It is in this regard settled case-law that the principle of non-discrimination requires that comparable situations must not be treated differently and that different situations must not be treated in the same way (see,   inter alia  , Case C-354/95   National Farmers' Union and Others   [1997] ECR I-4559, paragraph 61).  Such treatment may be justified only if it is based on objective considerations independent of the nationality of the persons concerned and is proportionate to the objective being legitimately pursued (see,   inter alia  ,   D'Hoop  , paragraph 36).
36.  As the Advocate General has pointed out in paragraph 56 of his Opinion, it is common ground that such a discrepancy in surnames is liable to cause serious inconvenience for those concerned at both professional and private levels resulting from,   inter alia  , difficulties in benefiting, in one Member State of which they are nationals, from the legal effects of diplomas or documents drawn up in the surname recognised in another Member State of which they are also nationals.  As has been established in paragraph 33 of the present judgment, the solution proposed by the administrative authorities of allowing children to take only the first surname of their father does not resolve the situation of divergent surnames which those here involved are seeking to avoid.