735 ILCS 5/2-804: Intervention by and exclusion of class members.

(a) Intervention. Any class member seeking to intervene or otherwise appear in the action may do so with leave of court and such leave shall be liberally granted except when the court finds that such intervention will disrupt the conduct of the action or otherwise prejudice the rights of the parties or the class.

(b) Exclusion. Any class member seeking to be excluded from a class action may request such exclusion and any judgment entered in the action shall not apply to persons who properly request to be excluded.