S.C. Code § 33-39-260
The charter may be amended by the votes of the stockholders and the members of the corporation, voting separately by classes, and such amendments shall require approval by the affirmative vote of two thirds of the votes to which the stockholders shall be entitled and two thirds of the votes to which the members shall be entitled; provided, that no amendment of the charter which is inconsistent with the general purposes expressed in this chapter, which authorizes any additional class of capital stock to be issued or which eliminates or curtails the right of the Secretary of State to examine the corporation or the obligation of the corporation to make reports as provided by law shall be made without amendment of this chapter; and provided, further, that no amendment of the charter which increases the obligation of a member to make loans to the corporation, makes any change in the principal amount, interest rate or maturity date or in the security or credit position of any outstanding loan of a member to the corporation, affects a member's right to withdraw from membership as provided in Section 33-39-430 or affects a member's voting rights as provided in Sections 33-39-440 and 33-39-450 shall be made without the consent of each member affected by such amendment.
S.C. Code § 33-39-260