Facts
[R.], born in 1987, is under legal incapacity and parental care. She receives a full disability pension from the Disability Insurance and a helplessness allowance. Since March 2005, she has lived during the week at the Foundation A. and on weekends and during holidays with her mother G., who has sole parental care. Until July 2009, the mother lived in X., Canton Zurich, before moving to [Y.] in Canton Aargau. By decision of the Municipal Council of Z./AG dated September 7, 2009, the supervision over the legally incapacitated [R.] was transferred from the guardianship authority of X. to that of the municipality of Z.
The municipality of X., which had previously paid the supplementary benefits (EL) to R.'s IV pension, requested the Social Insurance Institution of the Canton of Aargau, Compensation Fund (SVA Aargau), to determine and pay these benefits from August 2009 onwards. The Zurich municipality took the position that with the change of the insured person's domicile to the Canton of Aargau, the competence for the supplementary benefits had also passed to this canton.
Considerations
The Federal Supreme Court decided that the change of the derived civil law domicile of the legally incapacitated nursing home resident from X. to [Y.] in the Canton of Aargau led to a change in the local competence of the EL authorities. The exception in Art. 21 para. 1 second sentence ELG, according to which the stay in a nursing home as such does not change the competence, applies only to the stay in the nursing home itself, but not to other circumstances that determine…