S.C. Code Ann. § 33-43-801
(A) Subject to subsections (B) and (C), a person may become a member in a limited liability company:
(B) The effective time of admission of a member to a limited liability company shall be the later of:
(C) A domestic limited liability company formed in South Carolina and which renders professional service, as is defined in Section 33-43-102(N), may only admit as members:
(4) another foreign or domestic limited liability company in which all of the members are licensed in one or more states to practice a professional service which the limited liability company practices, and at least one member is authorized by law in this State to render such professional services.
If a licensing authority with jurisdiction over a professional considers it necessary to prevent violations of the ethical standards of the profession, the authority by rule may restrict or condition, or revoke in part, the authority of limited liability companies subject to its jurisdiction to permit persons or organizations to be members of limited liability companies.