Section 15(b) in The Chennai Corporation Officers Service Rules, 1975
(b)The claims of members of the Scheduled Castes and Scheduled Tribes and the Backward Classes shall also be considered for the fifty one appointments which shall be filled on the basis of merit and where a candidate belonging to Scheduled Castes or Scheduled Tribes or Backward Classes is selected on the basis of merit, the number of posts reserved for Scheduled Castes and Scheduled Tribes or for Backward Classes, as the case may be, shall not in any way be affected.
