On 24 April 1973, a 13-judge Constitution Bench of the Supreme Court — the largest ever assembled in Indian constitutional adjudication — held by a 7:6 majority that Parliament's amending power under Article 368 does not extend to altering the basic structure of the Constitution. The petition had begun as a religious-property challenge by the head of the Edneer Mutt; it ended as the most consequential constitutional ruling in the Republic's history. A digest of the bench, the line-up of opinions, the doctrinal contribution that has since governed every constitutional amendment, and the cases that have applied it.