42 C.F.R. § 435.940
The income and eligibility verification requirements set forth in this section and §§ 435.945 through 435.960 are based on sections 1137, 1902(a)(4), 1902(a)(19), 1902(a)(46)(B), 1902(ee), 1903(r)(3), 1903(x), 1940, and 1943(b)(3) of the Act, and section 1413 of the Affordable Care Act. Nothing in the regulations in this subpart should be construed as limiting the State's program integrity measures or affecting the State's obligation to ensure that only eligible individuals receive benefits, consistent with parts 431 and 455 of this chapter, or its obligation to provide for methods of administration that are in the best interest of applicants and beneficiaries and are necessary for the proper and efficient operation of the plan, consistent with § 431.15 of this chapter and section 1902(a)(19) of the Act.
42 C.F.R. §435.940