215 ILCS 161/40

(a) No vision care organization that issues, delivers, amends, or renews a vision care plan on or after the effective date of this Act shall issue a vision care plan contract that requires: (1) an eye care provider to contract with a plan that offers supplemental or specialty health care services as a condition of contracting with a plan that offers basic health services; or (2) an eye care provider to contract with a vision care plan as a condition to participation in a medical plan or in-network. (b) A vision care plan may enter into an agreement with a health care plan to deliver routine vision care services that are covered under the enrollee's plan. (c) A vision care plan may act as a network regarding routine vision care services offered by a health care plan.