(820 ILCS 120/1) (from Ch. 48, par. 2251)
    Sec. 1. As used in this Act:
    (1) "Commission" means compensation accruing to a sales representative for payment by a principal, the rate of which is expressed as a percentage of the dollar amount of orders or sales or as a percentage of the dollar amount of profits.
    (2) When a commission becomes due shall be determined in the following manner:
        (A) The terms of the contract between the principal
    
and salesperson shall control;
        (B) If there is no contract, or if the terms of the
    
contract do not provide when the commission becomes due, or the terms are ambiguous or unclear, the past practice used by the parties shall control;
        (C) If neither (A) nor (B) can be used to clearly
    
ascertain when the commission becomes due, the custom and usage prevalent in this State for the parties' particular industry shall control.
    (3) "Principal" means a sole proprietorship, partnership, corporation or other business entity whether or not it has a permanent or fixed place of business in this State and which:
        (A) Manufactures, produces, imports, or distributes a
    
product for sale;
        (B) Contracts with a sales representative to solicit
    
orders for the product; and
        (C) Compensates the sales representative, in whole or
    
in part, by commission.
    (4) "Sales representative" means a person who contracts with a principal to solicit orders and who is compensated, in whole or in part, by commission, but shall not include one who places orders or purchases for his own account for resale or one who qualifies as an employee of the principal pursuant to the Illinois Wage Payment and Collection Act.
(Source: P.A. 86-586; 87-948.)