Mo. Rev. Stat. § 89.450
No owner, or agent of the owner, of any land located within the platting jurisdiction of any municipality, knowingly or with intent to defraud, may transfer, sell, agree to sell, or negotiate to sell that land by reference to or by other use of a plat of any purported subdivision of the land before the plat has been approved by the council or planning commission and recorded in the office of the appropriate county recorder unless the owner or agent shall disclose in writing that such plat has not been approved by such council or planning commission and the sale is contingent upon the approval of such plat by such council or planning commission. Any person violating the provisions of this section shall forfeit and pay to the municipality a penalty not to exceed three hundred dollars for each lot transferred or sold or agreed or negotiated to be sold; and the description by metes and bounds in the instrument of transfer or other document used in the process of selling or transferring shall not exempt the transaction from this penalty. A municipality may enjoin or vacate the transfer or sale or agreement by legal action, and may recover the penalty in such action.
§ 89.450, RSMo