S.D. Codified Laws § 58-6-32
A property insurer may without additional capital or additional surplus include such amount and kind of insurance against legal liability for injury, damage, or loss to the person or property of others, and for medical, hospital, and surgical expense related to such injury, as the director deems to be reasonably incidental to insurance of real property against fire and other perils under policies covering farm properties, or residential properties designed for occupancy by not more than four families, with or without incidental office, professional, private school, or studio occupancy by an insured, whether or not the premium or rate charged for certain perils so covered is specified in the policy. No insurer authorized as to property insurance only may pursuant to this section retain risk as to any one subject of insurance as to hazards, other than property insurance hazards, in an amount exceeding ten percent of its surplus to policyholders.
SDCL 58-6-32