Okla. Stat. tit. 30, § 30-3-313
Notice of petition in home state of respondent
If a petition for the appointment of a guardian or issuance of a
protective order is brought in this state and this state was not the
respondent’s home state on the date the petition was filed, in
addition to complying with the notice requirements of this state,
notice of the petition shall be given to those persons who would be
entitled to notice of the petition if a proceeding were brought in
the respondent’s home state. The notice shall be given in the same
manner as notice is required to be given in this state.