Okla. Admin. Code § 365:25-15-5
Whenever the Insurance Commissioner determines, pursuant to 36 O.S. § 6470.6, that the financial condition of a company warrants additional capital and surplus based upon the type, volume, and nature of insurance business transacted, he may require such additional capital in the form of a deposit with the Department . Such additional capital shall consist of cash, securities approved by the Insurance Commissioner, or a clean irrevocable letter of credit issued by a bank chartered by the State of Oklahoma or a member bank of the Federal Reserve System and approved by the Insurance Commissioner. The company may receive interest or dividends from said deposit or exchange the deposits for others of equal value with the approval of the Insurance Commissioner. If such company discontinues business, the Insurance Commissioner shall return such deposit only after being satisfied that all obligations of the company have been discharged.
Okla. Admin. Code § 365:25-15-5