1) A person born in India on or after 1 July 1987 is a citizen of India if either parent was a citizen of India at the time of the birth. Those born in India on or after 3 December 2004 are considered citizens of India only if both of their parents are citizens of India or if one parent is a citizen of India and the other is not an illegal migrant at the time of their birth.
2) further The Central Government may, on an application, register as a citizen of India under section 5 of the Citizenship Act 1955 any person (not being an illegal migrant) whose parents are registered as citizens of India.