735 ILCS 5/13-207
A defendant may plead a set-off or counterclaim barred by the statute of limitation or the statute of repose, while held and owned by him or her, to any action, the cause of which was owned by the plaintiff or person under whom he or she claims, before such set-off or counterclaim was so barred, and not otherwise. This section shall not affect the right of a bona fide assignee of a negotiable instrument assigned before due. The changes made to this Section by this amendatory Act of the 102nd General Assembly apply to claims initiated on or after the effective date of this amendatory Act of the 102nd General Assembly and to claims intentionally filed to preclude a defendant a reasonable opportunity to file a counterclaim within the original limitation period.
735 ILCS 5/13-207