35 ILCS 120/1g
On or before December 31, 1986, except as hereinafter provided, each entity otherwise eligible under exemption (11) of Section 2-5 of this Act and on and after the effective date of this amendatory Act of the 92nd General Assembly each entity otherwise eligible under exemption (9) of Section 2-5 of this Act shall make application to the Department for an exemption identification number. In the case of a corporation, society, association, foundation, or institution organized and operated exclusively for charitable purposes and that has more than 50 subsidiary organizations in Illinois, the Department, in its sole discretion, may issue one exemption identification number to be used by the parent organization and each subsidiary organization.
Each exemption identification number or renewal number shall be valid for 5 years after the first day of the month following the month of issuance. Not less than 3 months before the expiration date, an application for renewal shall be filed.
Each application for an exemption identification number or a renewal number shall contain information and be accompanied by documentation as shall be requested by the Department.
35 ILCS 120/1g