On 19 October 2006, a five-judge Constitution Bench upheld the constitutional validity of the 77th, 81st, 82nd and 85th Amendments — which together had inserted Articles 16(4A) and 16(4B) to provide for reservation in promotion for SC/ST and the carry-forward of unfilled reserved positions. The disposition articulated the three-pronged test that has governed promotion-reservation policy ever since: backwardness, inadequacy of representation, and administrative efficiency. A digest of the holding, the three-prong architecture, and the relationship with the *Indra Sawhney* and *Jarnail Singh* lines.