(815 ILCS 105/12) (from Ch. 17, par. 613)
    Sec. 12. In any action upon a note, bond, bill, or other instrument in writing, which has been assigned to or transferred by delivery to the plaintiff after it became due, a set-off to the amount of the plaintiff's debt may be made of a demand existing against any person or persons who shall have assigned or transferred such instrument after it became due, if the demand be such as might have been set-off against the assignor, while the note or bill belonged to him.
(Source: Laws 1895, p. 262.)