The Ninth Schedule to the Indian Constitution was added by

Schedules to the Constitution are lists appended to organise specific categories of laws or provisions. The Ninth Schedule, introduced together with Article 31-B, places the Acts listed in it beyond challenge on the ground that they violate Fundamental Rights such as the right to equality or (then) the right to property -- though the Supreme Court has since held, in I.R. Coelho v. State of Tamil Nadu (2007), that Ninth Schedule laws enacted after 24 April 1973 (the date of the Kesavananda Bharati judgment) remain open to judicial review if they damage the Constitution's basic structure.

The Ninth Schedule was inserted into the Constitution by the Constitution (First Amendment) Act, 1951 -- India's very first constitutional amendment -- to protect State land-reform and zamindari-abolition laws from being struck down by courts for violating the Fundamental Right to property. It originally listed 13 Acts.

• Eighth Amendment (1960): extended reserved-seat representation for Scheduled Castes, Scheduled Tribes and Anglo-Indians in legislatures by a further ten years -- it made no change to the Ninth Schedule.

• Ninth Amendment (1960): gave effect to the transfer of certain Berubari Union territory to Pakistan under the 1958 India-Pakistan agreement -- despite the matching number, it is unrelated to the Ninth Schedule of the Constitution.

• Forty-Second Amendment (1976): added a large number of further Acts to the Ninth Schedule's list and made several other sweeping constitutional changes (Preamble words, Fundamental Duties), but the Schedule itself had already existed for twenty-five years by then -- this amendment enlarged it, it did not create it.

The amendment that added the Ninth Schedule to the Constitution is the Constitution (First Amendment) Act, 1951.