Okla. Stat. tit. 12, § 2602
A witness may not testify to a matter unless evidence is introduced sufficient to support a finding that the witness has personal knowledge of the matter. Evidence to prove personal knowledge may consist of the witness’s own testimony . This rule is subject to the provisions of Section 2703 of this title.
Laws 1978, SB 276, c. 285, § 602, eff. October 1, 1978; Amended by Laws 2002, HB 1939, c. 468, § 42, eff. November 1, 2002 (superseded document available).