Ill. Admin. Code tit. 50 § 941.20
If the company opts not to obtain readily available information about the named insureds and drivers listed on the application to underwrite the risk prior to issuing the policy, the company shall not defeat, avoid or rescind the policy of insurance or deny an insurance claim based on obtaining the readily available information after a loss has occurred or a claim is filed. "Readily available information" is defined to be limited to the information that appears on the motor vehicle record (MVR) maintained by the Illinois Secretary of State and LexisNexis Comprehensive Loss Underwriting Exchange (C.L.U.E.) Auto Reports, or any of their corresponding subsequent equivalents. The company shall not defeat, avoid or rescind the policy of insurance or deny an insurance claim after identifying an undisclosed driver in the household unless the undisclosed individual was driving the vehicle at the time of the accident.
Ill. Admin. Code tit. 50, § 941.20