Mo. Rev. Stat. § 376.230: Changing of securities on deposit.

Any company shall have the right at any time to change the securities on deposit with the director of the department of commerce and insurance by substituting a like amount of the character required in the first instance and to withdraw any excess of securities; and so long as such company shall remain solvent, and the amount of its deposits as herein required are not impaired, it may collect the interest on the securities deposited as the same accrues.