S.C. Code § 12-54-225
The department may enter into agreements with other states of the United States or their authorized representatives for the mutual exchange of tax returns, information thereon, and related information. The department may, if it chooses, designate a third person to act as its agent for the receipt and exchange of the returns and information, including the assimilation of the material for proper use. The exchange may be in any form suitable to the parties, including, but not limited to, cards, tapes, and other electronic means. The returns and information exchanged may be used for the exclusive purpose of administering the tax laws of the exchanging jurisdictions, including any administrative or judicial proceeding that involves the administration, collection, or recovery of any tax. The agreements may be on such terms and conditions as the department and the other states may agree and designate. However, any such agreement entered into by the department must include a provision that the agreement may be canceled upon notice.
S.C. Code § 12-54-225