Mo. Rev. Stat. § 443.080
The trustee, or trustees, in any security instrument given or which may hereafter be given by a railroad company or other public utility company which is subject to the regulation of the motor carrier and railroad safety division of the department of economic development, or successors, upon its property or any part thereof, may enter satisfaction of said security instrument upon the records where the same has been recorded. Where such security instrument was recorded prior to January 1, 1986, without producing the bonds, notes or coupons secured by said security instrument, satisfaction shall not be entered unless the trustee, or if said trustee is a corporation, its president or vice president, and the president or vice president of the railroad company or other public utility company, or of its successors or assigns, shall make and file with the recorder affidavits stating that all of the bonds, notes or coupons secured by said security instrument have been paid or that sufficient funds have been deposited with a bank or trust company to pay all the bonds, notes or coupons still outstanding and unpaid; and that said money is deposited for the express purpose of paying said bonds, notes or coupons when the same shall be presented at said bank or trust company for payment.
§ 443.080, RSMo
Effective 1/1/1986