Constitution of India, 1949
5.Citizenship at the commencement of the
Constitution.-
At the commencement of this Constitution every
person who has his domicile in the territory of India and -
(a) who was born in the territory of India; or
(b) either of whose parents was born in the
territory of India; or
(c) who has been ordinarily resident in the
territory of India for not less than five years preceding such commencement,
shall be a citizen of India.