E/C.12/GC/19 page 13 allocate adequate fiscal and other resources at the national level. If necessary, they should avail themselves of international cooperation and technical assistance in line with article 2, paragraph 1, of the Covenant. 42. There is a strong presumption that retrogressive measures taken in relation to the right to social security are prohibited under the Covenant. If any deliberately retrogressive measures are taken, the State party has the burden of proving that they have been introduced after the most careful consideration of all alternatives and that they are duly justified by reference to the totality of the rights provided for in the Covenant, in the context of the full use of the maximum available resources of the State party. The Committee will look carefully at whether: (a) there was reasonable justification for the action; (b) alternatives were comprehensively examined; (c) there was genuine participation of affected groups in examining the proposed measures and alternatives; (d) the measures were directly or indirectly discriminatory; (e) the measures will have a sustained impact on the realization of the right to social security, an unreasonable impact on acquired social security rights or whether an individual or group is deprived of access to the minimum essential level of social security; and (f) whether there was an independent review of the measures at the national level. B. Specific legal obligations 43. The right to social security, like any human right, imposes three types of obligations on States parties: the obligation to respect, the obligation to protect and the obligation to fulfil. 1. Obligation to respect 44. The obligation to respect requires that States parties refrain from interfering directly or indirectly with the enjoyment of the right to social security. The obligation includes, inter alia, refraining from engaging in any practice or activity that, for example, denies or limits equal access to adequate social security; arbitrarily or unreasonably interferes with self-help or customary or traditional arrangements for social security; arbitrarily or unreasonably interferes with institutions that have been established by individuals or corporate bodies to provide social security. 2. Obligation to protect 45. The obligation to protect requires that State parties prevent third parties from interfering in any way with the enjoyment of the right to social security. Third parties include individuals, groups, corporations and other entities, as well as agents acting under their authority. The obligation includes, inter alia, adopting the necessary and effective legislative and other measures, for example, to restrain third parties from denying equal access to social security schemes operated by them or by others and imposing unreasonable eligibility conditions; arbitrarily or unreasonably interfering with self-help or customary or traditional arrangements for social security that are consistent with the right to social security; and failing to pay legally required contributions for employees or other beneficiaries into the social security system. 46. Where social security schemes, whether contributory or non-contributory, are operated or controlled by third parties, States parties retain the responsibility of administering the national social security system and ensuring that private actors do not compromise equal, adequate,