Okla. Stat. tit. 6, § 6-411

A. A bank may pledge its assets to:

1. Enable it to act as agent for the sale of obligations of the

United States;

2. Secure borrowed funds;

3. Secure deposits when the depositor is required to obtain

such security by the laws of the United States, by the terms of any

interstate compact, by the laws of any state or by order of a court

of competent jurisdiction;

4. Secure the uninsured portion of deposits made by a

governmental agency of the State of Oklahoma, any public trust

having the State of Oklahoma as a beneficiary, rural water district,

nonprofit rural water corporation or master conservancy districts

formed pursuant to the Conservancy Act of Oklahoma, so long as the

pledge is made with the same type of collateral and in the same

manner and form as pledges made to secure deposits by the State

Treasurer;

5. Anyone as permitted by national banks; or

6. Otherwise comply with the provisions of this Code.

B. In the event the bank pledges assets pursuant to subsection

A of this section, the bank shall maintain in its files

documentation showing the legal authority or basis for such

pledging.

C. With respect to the pledge of assets for deposits identified

in subsections A and B of this section, any such pledge shall only

apply to the portion not insured by the Federal Deposit Insurance

Corporation.