There is exempted from the provisions of this chapter and from the computation of the tax imposed by it, freeport merchandise and stocks of merchandise brought as foreign or domestic merchandise into a foreign trade zone. For the purposes of this section, stocks of merchandise is personal property which is held primarily for sale and not subject to annual depreciation. However, the exemption only applies if written evidence of the contract of sale is retained, and such contract indicates that the merchandise is to be shipped in international commerce to a point outside the United States not to be returned to a point within the United States.
SDCL 10-45-10.3