S.C. Code Ann. § 20-7-1010 – Determination of jurisdiction where multiple tribunals have issued child support orders

(A) If a proceeding is brought under this subarticle and only one tribunal has issued a child support order, the order of that tribunal is controlling and must be recognized.
(B) If a proceeding is brought under this subarticle and two or more child support orders have been issued by tribunals of this State or another state with regard to the same obligor and child, a tribunal of this State shall apply the following rules in determining which order to recognize for purposes of continuing, exclusive jurisdiction:
1. (1) if only one of the tribunals would have continuing, exclusive jurisdiction under the provisions of this subarticle, the order of that tribunal is controlling and must be recognized;
2. (2) if more than one of the tribunals would have continuing, exclusive jurisdiction under the provisions of this subarticle, an order issued by a tribunal in the current home state of the child must be recognized, however, if an order has not been issued in the current home state of the child, the order most recently issued is controlling and must be recognized;
3. (3) if none of the tribunals would have continuing, exclusive jurisdiction under the provisions of this subarticle, a tribunal of this State having jurisdiction over the parties must issue a child support order which is controlling and must be recognized.
(C) If two or more child support orders have been issued for the same obligor and child and if the obligor or the individual obligee resides in this State, a party may request a tribunal of this State to determine which order controls and must be recognized under subsection (B). The request must be accompanied by a certified copy of every support order in effect. Every party whose rights may be affected by a determination of the controlling order must be given notice of the request for that determination.
(D) The tribunal that issued the order that must be recognized as controlling under subsection (A), (B), or (C) is the tribunal that has continuing, exclusive jurisdiction in accordance with Section 20-7-1000.
(E) A tribunal of this State which determines by order the identity of the controlling child support order under subsections (B)(1) or (B)(2) or which issues a new controlling child support order under subsection (B)(3) shall include in that order the basis upon which the tribunal made its determination.
(F) Within thirty days after issuance of the order determining the identity of the controlling order, the party obtaining that order shall file a certified copy of it with each tribunal that had issued or registered an earlier order of child support. Failure of the party obtaining the order to file a certified copy as required subjects that party to appropriate sanctions by a tribunal in which the issue of failure to file arises, however, that failure has no effect on the validity or enforceability of the controlling order.