Mo. Rev. Stat. § 379.690

There shall be filed with the director of the department of commerce and insurance of this state, by the attorney, a statement under the oath of the attorney, showing in the case of fire insurance, the maximum amount of indemnity upon any single risk, and the attorney shall, whenever and as often as the same shall be required, file with the director of the department of commerce and insurance a statement verified by his oath to the effect that he has examined the commercial rating of the subscribers as shown by the reference book of a commercial agency having at least one hundred thousand subscribers, and that from the examination or from * other information in his possession, it appears that no subscriber has assumed on any single fire insurance risk an amount greater than ten percent of the net worth of the subscriber.