Mo. Rev. Stat. § 456.5-502: Spendthrift provision.

1. A spendthrift provision is valid if it restrains either the voluntary or involuntary transfer or both the voluntary and involuntary transfer of a beneficiary's interest.

2. A term of a trust providing that the interest of a beneficiary is held subject to a "spendthrift trust," or words of similar import, is sufficient to restrain both voluntary and involuntary transfers of the beneficiary's interest.

3. A beneficiary may not transfer an interest in a trust in violation of a valid spendthrift provision and, except as otherwise provided in sections 456.5-501 to 456.5-507, a creditor or assignee of the beneficiary may not reach the interest or a distribution by the trustee before its receipt by the beneficiary.