Mo. Rev. Stat. § 522.300
Every person furnishing material or performing labor, either as an individual or as a subcontractor for any contractor, with the state, or any county, city, town, township, school or road district, where bond shall be executed as provided in section 107.170, shall have the right to sue on such bond in the name of the state, county, city, town, township, school or road district, for his use and benefit, and in such suit the plaintiff shall file a copy of such bond, certified by the party or parties in whose charge such bond shall be, which copy shall, unless execution thereof be denied under oath, be prima facie evidence of the execution and delivery of the original; provided, however, this section and section 107.170 shall not be taken to in any way make the state, county, city, town, township, school or road district liable to such subcontractor, materialman or laborer to any greater extent than it was liable under the law as it stood before the adoption originally of said sections.
§ 522.300, RSMo
RSMo 1939 § 3278