Now some state governments have come with directive clarifying that 1.Caste certificate is permanent. 2.Income certificate is valid for four years from date of issue and other certificates as per the issue. While taking up for domicile, educational certificates are valid as they show the courses, colleges, university where the candidate appeared and qualified for the examination. Tenth Certificate, +2 (intermediate), Degree are themselves domicile certificates and unless there is variation in the places, authorities should not normally insist for domicile certificate. Further classification of castes may be different from state to state. In one state a caste may be backward and in other states it may be OC. So caste certificates are valid on the basis of that state rules.