Michigan Compiled Laws, Chapter 500. Insurance Code of 1956 § 500.938

(a) Any negotiable paper or other evidence of indebtedness secured by any of the classes of securities in which insurance companies may lawfully invest funds pursuant to sections 912 and 918.  2

(b) Negotiable notes secured by pledge of stock of national or state banks, which have a surplus equal in amount to 25% of the paid in capital stock provided those loans do not exceed 85% of the market value of the stock and the total amount of the loan on bank secured collateral does not exceed 15% of the capital and surplus of the insurance company.

(c) For other than a life insurer, loans secured as collateral by corporate stocks and securities eligible for investment under section 922  3 but no loan shall be made of more than 50% of the fair market value of those stocks and securities.