S.C. Code Ann. § 29-3-440

Such satisfaction and cancellation of the mortgage or release of the lien thereof shall be effectual and binding upon the parties so served with the petition and rule and upon every assignee or pledgee of every parol or written assignment, pledge or hypothecation of such mortgage not named in and served with the petition and rule unless such pledge, hypothecation or assignment is duly recorded in the proper office at or before the time of the filing of the petition or the petitioner has actual notice or knowledge thereof.