40 ILCS 5/15-106
"Employer": The University of Illinois, Southern Illinois University, Chicago State University, Eastern Illinois University, Governors State University, Illinois State University, Northeastern Illinois University, Northern Illinois University, Western Illinois University, the State Board of Higher Education, the Illinois Mathematics and Science Academy, the University Civil Service Merit Board, the Board of Trustees of the State Universities Retirement System, the Illinois Community College Board, community college boards, any association of community college boards organized under Section 3-55 of the Public Community College Act, the Board of Examiners established under the Illinois Public Accounting Act, and, only during the period for which employer contributions required under Section 15-155 are paid, the following organizations: the alumni associations, the foundations and the athletic associations which are affiliated with the universities and colleges included in this Section as employers. An individual who begins employment on or after the effective date of this amendatory Act of the 99th General Assembly with any association of community college boards organized under Section 3-55 of the Public Community College Act, the Association of Illinois Middle-Grade Schools, the Illinois Association of School Administrators, the Illinois Association for Supervision and Curriculum Development, the Illinois Principals Association, the Illinois Association of School Business Officials, the Illinois Special Olympics, or an entity not defined as an employer in this Section shall not be deemed an employee for the purposes of this Article with respect to that employment and shall not be eligible to participate in the System with respect to that employment; provided, however, that those individuals who are both employed by such an entity and are participating in the System with respect to that employment on the effective date of this amendatory Act of the 99th General Assembly shall be allowed to continue as participants in the System for the duration of that employment.
A department as defined in Section 14-103.04 is an employer for any person appointed by the Governor under the Civil Administrative Code of Illinois who is a participating employee as defined in Section 15-109. The Department of Central Management Services is an employer with respect to persons employed by the State Board of Higher Education in positions with the Illinois Century Network as of June 30, 2004 who remain continuously employed after that date by the Department of Central Management Services in positions with the Illinois Century Network, the Bureau of Communication and Computer Services, or, if applicable, any successor bureau or the Department of Innovation and Technology.
The cities of Champaign and Urbana shall be considered employers, but only during the period for which contributions are required to be made under subsection (b-1) of Section 15-155 and only with respect to individuals described in subsection (h) of Section 15-107.
40 ILCS 5/15-106