Okla. Stat. tit. 84, § 84-24: Time for filing disclaimer

Such disclaimer shall be filed at any time after the creation of

the interest, but in all events within nine (9) months after the

death of the person by whom the interest was created or from whom it

would have been received, or, if the disclaimant is not finally

ascertained as a beneficiary or his interest has not become

indefeasibly fixed both in quality and quantity as of the death of

such person, then such disclaimer shall be filed not later than nine

(9) months after the event which would cause him so to become

finally ascertained and his interest to become indefeasibly fixed

both in quality and quantity.