Okla. Stat. tit. 70, § 70-4009: Public funds, etc., may be invested in bonds

Any bank, trust or insurance company organized under the laws of

Oklahoma may invest its capital, surplus and reserves in bonds

issued under the provisions of this article. The officers having

charge of any sinking fund or any other fund of the state or any

department, agency or institution thereof, including the various

funds established by Article 17 of the Oklahoma School Code, or any

county, city, town, or school district in the state, may invest such

funds in bonds issued under the provisions of this article at the

reasonable market value thereof. Such bonds are also approved as

collateral security for the deposit of any public funds and for the

investment of trust funds.