815 ILCS 505/2DD
A telecommunication carrier shall not submit or execute a change in a subscriber's selection of a provider of local exchange telecommunications service or interexchange telecommunications service or offer or provide a product or service to be billed on the telephone bill as provided in Sections 13-902 and 13-903 of the Public Utilities Act except in accordance with (i) the verification procedures adopted by the Federal Communications Commission under the Communications Act of 1996, including subpart K of 47 CFR 64, as those procedures are from time to time amended, and (ii) Sections 13-902 and 13-903 of the Public Utilities Act and any rules adopted by the Illinois Commerce Commission under the authority of that Section as those rules are from time to time amended. A telecommunications carrier that violates this Section commits an unlawful practice within the meaning of this Act.
815 ILCS 505/2DD