Okla. Stat. tit. 22, § 765
If the court or judge is satisfied that the examination of the witness is necessary an order must be made that the witness be examined conditionally at a specified time and place, and that a copy of the order be served on counsel for the opposing party within a specified time before that fixed for the examination.
R.L. 1910, § 6029; Amended by Laws 1994, SB 666, c. 292, § 9, eff. September 1, 1994.