§1. A private association of the Christian faithful can acquire juridic personality through a formal decree of the competent ecclesiastical authority mentioned in can. 312.
§2. No private association of the Christian faithful can acquire juridic personality unless the ecclesiastical authority mentioned in can. 312, §1 has approved its statutes. Approval of the statutes, however, does not change the private nature of the association.
Source: Code of Canon Law (Vatican.va)