Mo. Rev. Stat. § 382.515: ORSA to be conducted, when.

Subject to the provisions of section 382.525, an insurer or the insurance group of which the insurer is a member shall conduct an ORSA consistent with a process comparable to the ORSA guidance manual. An ORSA shall be conducted no less than annually and additionally at any time when there are significant changes to the risk profile of the insurer or the insurance group of which the insurer is a member, as determined by the insurer or the insurance group.