Missouri Constitution
Article IV - Executive Department
Section 14 Secretary of state—duties—state seal—official register—limitation on duties.

The secretary of state shall be custodian of the seal of the state, and authenticate therewith all official acts of the governor except the approval of laws. The seal shall be called the “Great Seal of the State of Missouri,” and its present emblems and devices shall not be subject to change. He shall keep a register of the official acts of the governor, attest them when necessary, and when required shall lay copies thereof, and of all papers relative thereto, before either house of the general assembly. He shall be custodian of such records, and documents and perform such duties in relation thereto, and in relation to elections and corporations, as provided by law, but no duty shall be imposed on him by law which is not related to his duties as prescribed in this constitution.

Source: Const. of 1875, Art. IV, Secs. 20, 21.