Okla. Stat. tit. 58, § 58-268: Action against nonprobate beneficiaries for state and

federal estate tax - Notice - Costs and attorney fees.

For property other than the probate estate passing directly upon

the death of a decedent to another, by law, the executor or

administrator of the estate of the decedent shall have the authority

to bring an action in the district court having jurisdiction of the

probate estate for the collection of any of the state or federal

estate tax due and owing by the nonprobate beneficiaries after ten

(10) days following service of notice by such executor or

administrator upon such nonprobate beneficiary before suit is filed.

Such notice shall state the amount of federal or state tax due to

the executor or administrator by the nonprobate beneficiary. In

such actions, the court costs and reasonable attorney fees may be

assessed in favor of the prevailing party.