Okla. Stat. tit. 36, § 6912
With the exception of investments made in accordance with the provisions of paragraph 1 of subsection A of Section 5 of this act, the funds of a health maintenance organization shall be invested only in accordance with the provisions of Article 16 of the Insurance Code. Historical Data Laws 2003, SB 635, c. 197, § 12, eff. November 1, 2003.