Okla. Stat. tit. 11 § 38-116
All banks, trust companies, bankers, savings banks and institutions, building and loan associations, savings and loan associations, investment companies and other persons carrying on a banking or investment business; all insurance companies, insurance associations, and other persons carrying on an insurance business; and all executors, administrators, curators, trustees, and other fiduciaries, may legally invest in sinking funds, moneys, or other funds belonging to them or within their control in any notes or other obligations issued by a municipality or an Urban Renewal Authority pursuant to this article and vested with urban renewal project powers under this article; Provided, that such notes, bonds or other obligations may be secured by an agreement between the issuer and the Federal Government in which the issuer agrees to borrow from the Federal Government and the Federal Government agrees to lend to the issuer, prior to the maturity of such notes, bonds or other obligations, moneys in an amount which (together with any other moneys irrevocably committed to the payment of interest on such notes, bonds or other obligations) will suffice to pay the principal of such notes, bonds or other obligations with interest to maturity thereon, which moneys under the terms of said agreements are required to be used for the purpose of paying the principal and interest of such notes, bonds or other obligations at their maturity. Such notes, bonds and other obligations shall be authorized security for all public deposits. It is the purpose of this section to authorize any persons, political subdivision and officers, public or private, to use any funds owned or controlled by them for the purchase of any such notes, bonds or other obligations. Nothing contained in this section with regard to legal investments shall be construed as relieving any person of any duty of exercising reasonable care in selecting securities.
Okla. Stat. tit. 11, § 38-116