35 ILCS 200/21-250
The county clerk shall make out and deliver to the purchaser of any property sold under Section 21-205, or to the county if the lien is acquired pursuant to Section 21-90 and a certificate is requested by the county or its agent, a tax certificate countersigned by the collector, describing the property sold, the date of sale, the amount of taxes, special assessments, interest and cost for which they were sold and that payment of the sale price has been made. If any person becomes the purchaser of more than one property owned by one party or person, the purchaser may have the whole or one or more of them included in one certificate, but separate certificates shall be issued in all other cases. A tax certificate shall be assignable by endorsement. An assignment shall vest in the assignee or his or her legal representatives, all the right and title of the original purchaser.
If the tax certificate is lost or destroyed, the county clerk shall issue a duplicate certificate upon written request and a sworn affidavit by the tax sale purchaser, or his or her assignee, that the tax certificate is lost or destroyed. The county clerk shall cause a notation to be made in the tax sale and judgment book that a duplicate certificate has been issued, and redemption payments shall be made only to the holder of the duplicate certificate.
35 ILCS 200/21-250