The National Commission for Backward Classes Act, 1993

11. Periodic revision of lists by the Central Government.

1. The Central Government may at any time, and shall, at the expiration of ten years from the coming into force of this Act and every succeeding period of ten years thereafter, undertake revision of the lists with a view to excluding from such lists those classes who have ceased to  be backward classes or for including in such lists new backward classes. 
2. The Central Government shall, while undertaking any revision referred to in sub-section (1), consult the Commission.