Okla. Stat. tit. 68, § 68-2364: Estates, trusts and beneficiaries

A. The Oklahoma taxable income or loss of an estate, trust or

any beneficiary of either shall be the same portion of that reported

for federal income tax purposes as the Oklahoma income, gains,

losses or deductions determined under applicable provisions of this

act for said estate, trust and/or beneficiary bears to the federal

income, gains, losses or deductions. Amounts allowable under the

Oklahoma Estate Tax Law as deductions in computing the taxable

estate of a decedent shall not be allowed as deductions in computing

the taxable income of the estate or of any other person unless there

is filed, as provided in Internal Revenue Code, Section 642, or any

provisions comparable thereto, the statement required therein and if

such waiver is filed then to the extent allowed as a deduction for

income tax purposes, such amount shall not be allowed for estate tax

purposes.

B. A beneficiary of a trust shall exclude from Oklahoma taxable

income any excess distributions by trusts required to be included in

the beneficiary's federal taxable income by reason of Sections 665

through 669 of the Internal Revenue Code, or any provisions

comparable thereto.