Citizenship Act, 1955
6. Citizenship by naturalization
(1) Where an application is made in the prescribed manner by any person of full age and capacity who is not a citizen of a country specified in Schedule I for the grant of a certificate of naturalization to him, the Central Government may, if satisfied that the applicant is qualified for naturalization under the provisions of Schedule III, grant to him, a certificate of naturalization:
PROVIDED that, if in the opinion of the Central Government, the applicant is a person who has rendered distinguished service to the cause of science, philosophy, art, literature, world peace or human progress generally, it may waive all or any of the conditions specified in Third Schedule III.
(2) The person to whom a certificate of naturalization is granted under sub-section (1) shall, on taking the oath of allegiance in the form specified in Schedule II, be a citizen of India by naturalization as from the date on which that certificate is granted.