Okla. Stat. tit. 62 § 513
The State Treasurer, and the treasurers of counties, school districts, cities, towns, municipalities and any other political subdivision of the state, and any other officer, board, department or commission having custody, control and management of any public or trust fund or funds charged with the safekeeping and deposit of said funds or funds are hereby specifically authorized to deposit said fund or funds in any federally-insured building and loan association wherever located, whether federally or state chartered, in an amount and to the extent that such deposit is fully insured by the Federal Savings and Loan Insurance Corporation or any other instrumentality of the United States Government. When any such insured deposit is made it shall not be necessary for such treasurer, officer, board, department or commission to require any security, and such insurance shall be accepted in lieu of any security, restriction or other limitation now required or imposed by law upon the deposit of public funds.
Okla. Stat. tit. 62, § 513