SDCL § 58-34-25: Eligibility to become subscriber.

Individuals, partnerships, associations, and corporations, public or private, of this state, hereby designated as subscribers, are authorized to exchange reciprocal or interinsurance contracts with each other, or with individuals, partnerships, associations, and corporations, public or private, of other states and countries, providing indemnity among themselves for any loss which may be insured against by the reciprocal insurer to which they are subscribers; except, that public corporations of this state may so insure only in an insurer which has a surplus of three hundred thousand dollars or more and under an insurance contract as to which such an insured has no contingent liability.