Please do not discuss caste here, because OBC means "Other Backword Classes". Even poor among the upper caste can be OBC. Those political parties who want to divide the country on the basis of caste can not claim to be "secular". As per constitution there is no doubt about the reservation for SC & ST. I think SC STs should strongly oppose the OBC reservation, because it will dilute the cause of SC/ST and zeoperdise the whole issue of resrvation. As far as torture, descrimination, opression on the basis of caste is concerned, it was the SCs who suffered the most in the hands of the upper caste as well as other backward caste. STs require reservation to bring them into the main stream.