The common substantial questions of law, propounded and posed for consideration in all the above appeals are: (1) Whether the second proviso to Rule 4 of the CSE Rules 1986 is invalid for the reason that it puts an embargo restricting the candi dates who are seeking to improve their posi tion vis a 62 vis their career in Government service? (2) Whether the second proviso under chal lenge travels beyond the intent of the main rule namely, Rule 4 of the CSE Rules? (3) Whether the proviso to Rule 17 of the CSE Rules is invalid on the ground that it places restriction on candidates who are seeking to improve their position vis a vis their career? (4) Whether the said second proviso to Rule 4 of CSE Rules is ultra vires to clause (iii a) of Regulation 4 of the Indian Administrative Service (Appointment by Competitive Examina tion) Regulations, 1955 (for short 'Regula tions ') inasmuch as the power to notify excep tions does not include the power to make candidates ineligible who are otherwise eligi ble in terms of clauses (i), (ii) and (iii) of Regulation 4? (5) Whether the said proviso which is an administrative instruction introduced by the impugned Notification is arbitrary and irra tional having no nexus with the object of recruitment to the post of Civil Services? (6) Whether the impugned second proviso is illegal since it makes a discrimination be tween the successful candidates of Central Service Group 'A ' and Group 'B ' as no embargo is placed restricting the candidates of Group 'B ' service, as in the case of Group 'A ' service and whether the reasons given by the Government to justify the introduction of the impugned proviso have any rational nexus to the object of the scheme of recruitment to the All India Services or/and whether such reasons are arbitrary, unfair and unjust? (7) Whether the restriction imposed on the number of attempts in pursuance of the im pugned proviso, in the case of Scheduled Castes/Scheduled Tribes candidates who were since then availing any number of attempts subject to the eligibility of age limit is unjustifiable and illegal and amounts to deprivation of the right conferred on them by the Constitution of India? (8) Whether the reasons given by the Govern ment to justify the introduction of the im pugned proviso have any rational 63 nexus to the object of the scheme of recruit ment to the All lndia Services or/and whether such reasons are arbitrary, unfair and unjust? (9) Whether the impugned second proviso is suffering from the vice of hostile discrimina tion and as such violative of Articles 14 and 16 of the Constitution of India.