Okla. Stat. tit. 22, § 22-791: Filing commission and return

The clerk or judge receiving and opening the commission and

return must immediately file it, with the affidavit mentioned in the

last two sections, in the office of the clerk of the court in which

the indictment or information is pending. If the commission and

return is transmitted by mail, the clerk to whom it is addressed

must receive it from the post office, and open and file it in his

office, where it must remain unless otherwise directed by the court.