Nigeria Constitution 1999, Chapter III on Citizenship
25. (1) The following persons are citizens of Nigeria by birth, namely-
(a) every person born in Nigeria before the date of independence, either of whose parents or any of whose grandparents belongs or belonged to a community indigenous to Nigeria; Provided that a person shall not become a citizen of Nigeria by virtue of this section if neither of his parents nor any of his grandparents was born in Nigeria.
(b) every person born in Nigeria after the date of independence either of whose parents or any of whose grandparents is a citizen of Nigeria; and
(c) every person born outside Nigeria either of whose parents is a citizen of Nigeria. (2) In this section, “the date of independence” means the 1st day of October 1960.
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