5 ILCS 100/1-75
"Small business" means a corporation or a concern, including its affiliates, that is independently owned and operated, not dominant in its field, and employs fewer than 50 full-time employees or has gross annual sales of less than $4,000,000. For purposes of a specific rule, an agency may define small business to include employment of 50 or more persons if it finds that such a definition is necessary to adapt the rule to the needs and problems of small businesses and organizations.
(from Ch. 127, par. 1001-75)
(Source: P.A. 87-823.)