Mo. Rev. Stat. § 436.318: Release of retainage, payment made.

Upon the release of retainage by the owner to the contractor, other than for substituted security pursuant to sections 436.306 and 436.312, the contractor shall pay to each subcontractor the subcontractor's ratable share of the retainage released, provided that all conditions of the subcontract for release of retainage to the subcontractor have been satisfied.