20 ILCS 1605/19
The Department shall establish an appropriate period for the claiming of prizes for each lottery game offered. Each claim period shall be stated in game rules and written play instructions issued by the Director in accordance with Section 7.1 of this Act. Written play instructions shall be made available to all players through sales agents licensed to sell game tickets or shares. Prizes for lottery games which involve the purchase of a physical lottery ticket may be claimed only by presentation of a valid winning lottery ticket that matches validation records on file with the Lottery; no claim may be honored which is based on the assertion that the ticket was lost or stolen. No lottery ticket which has been altered, mutilated, or fails to pass validation tests shall be deemed to be a winning ticket.
If no claim is made for the money within the established claim period, the prize may be included in the prize pool of such special drawing or drawings as the Department may, from time to time, designate. Unclaimed multi-state game prize money may be included in the multi-state prize pool for such special drawing or drawings as the multi-state game directors may, from time to time, designate. Any bonuses offered by the Department to sales agents who sell winning tickets or shares shall be payable to such agents regardless of whether or not the prize money on the ticket or share is claimed, provided that the agent can be identified as the vendor of the winning ticket or share, and that the winning ticket or share was sold on or after January 1, 1984. All unclaimed prize money not included in the prize pool of a special drawing shall be transferred to the Common School Fund.
20 ILCS 1605/19