Article 21(1) TFEU must be interpreted as not precluding legislation of a Member State which does not provide for the grant of a derived right of residence in another Member State, under Union law, to a third-country national family member of a Union citizen who is a national of that Member State and who returns there after having resided, pursuant to and in conformity with Union law, in another Member State, when the family member of the Union citizen concerned has not entered the territory of the Member State of origin of the Union citizen or has not applied for a residence permit as a ‘natural consequence’ of the return to that Member State of the Union citizen in question, provided that such rules require, in the context of an overall assessment, that other relevant factors also be taken into account, in particular factors capable of showing that, in spite of the time which elapsed between the return of the Union citizen to that Member State and the entry of the family member who is a third-country national, in the same Member State, the family life created and strengthened in the host Member State has not ended, so as to justify the granting to the family member in question of a derived right of residence; it is for the referring court to verify whether this is the case.

As the grant of a derived right of residence on the basis of Article 21(1) TFEU aims to allow the continuation, in the Member State of which the Union citizen concerned is a national, of the family life which has been created or strengthened with a family member who is a third-country national in the host Member State, the competent authorities of the Member State of which the Union citizen has the nationality are entitled to verify, before granting such a right of residence, that such a family life between the Union citizen and the third-country national who is a member of his family had not been interrupted before the entry of the third country national into the Member State of which the Union citizen in question is a national.

For the purposes of such verification, the Member State concerned may take into account, as an indication, that the third-country national, who is a family member of one of its own citizens, entered its territory a significant period of time after that citizen’s return to that territory.

However, it cannot be ruled out that a family life, created or strengthened between a Union citizen and a member of his or her family who is a third-country national, during their stay, pursuant to and in conformity with Union law, in the host Member State, might continue despite the fact that that citizen has returned to the Member State of which he is a national without being accompanied by the family member in question, who may have been obliged, for reasons relating to his personal situation, profession or education, to delay his arrival in the Member State of origin of the Union citizen in question.

Accordingly, the fact that the submission of the application for a residence permit was not ‘a natural consequence’ of the return of the Union citizen is a relevant factor which, although not decisive in itself, may, in the context of an overall assessment, lead the Member State of origin of the Union citizen in question to conclude that there is no link between the application and the exercise by that citizen of his freedom of movement and, consequently, to refuse to issue such a residence permit.

(see paras 31-35, operative part)