The 93rd Constitutional Amendment Act, 2005, inserted Clause (5) in Article 15 of the Constitution. This clause enables the state to make special provisions for the advancement of any socially and educationally backward classes of citizens or for the Scheduled Castes or the Scheduled Tribes in so far as such special provisions relate to their admission to educational institutions, including private educational institutions, whether aided or unaided by the State, other than the minority educational institutions referred to in Clause (1) of Article 30. This amendment provided the constitutional basis for implementing 27% reservation for OBCs in central government educational institutions.