Okla. Stat. tit. 60, § 60-175.87
Creditor attachment of mandatory distributions
A. If a trust created on or after November 1, 2010, contains a
spendthrift provision, a creditor shall not attach present and
future mandatory distributions from the trust. A creditor shall
wait until a distribution is received by a beneficiary before
attachment. However, an exception creditor may attach present and
future mandatory distributions for child support.
B. If a trust does not contain a spendthrift provision, a
creditor may attach present and future mandatory distributions from
the trust at the trust level.
C. A beneficiary holding a mandatory distribution interest may
enforce the interest. A court may review the distribution
discretion of a trustee if the trustee acts beyond the bounds of
reasonableness.