A seperate inheritance governed by its own statutes
The Sacred Military Constantinian Order of Saint George received confirmation as a Religious-Military Order from the Holy See and, with the Sovereign Military Order of Malta, is the only international Catholic Order which has maintained this status unchanged to the present day. It is a subject of Roman Catholic Canon Law. The Order is dedicated to propaganda of the Faith, Defence of the Church and support of the Holy See; the members owe a particular duty of loyalty to the Pope and to support the teachings and dogma of the Roman Catholic Church.
Since 1731 this has been the inheritance of the Bourbon family descended from Philip V of Spain and his wife Elizabeth Farnese.
The Constantinian Grand Magistery is an inheritance by male primogeniture from the Farnese dynasty. On the extinction of the latter, the succession passed with Papal assent to the nearest male heir, the Infante don Carlos de Borbón y Farnese (later Charles III of Spain). In 1759, after the latter transferred his Neapolitan Crown to his third son Ferdinand, the Constantinian Grand Magistery was ceded in a separate act ten days later, the young King Ferdinand being declared "legitimate primogeniture male heir of the Farnese".
The succession to the Constantinian Grand Magistery can only pass to males and, on the extinction of the last male descendant of Charles III, it passes to the Bourbon-Parma line.