Holy See of the East the Church of the East after the Coonan Cross Oath and joined the Church of Antioch also claims the title of the Holy See of the East, since St. Thomas is also the founder of this churches. The Malankara Orthodox Syrian Church which evolved out of the Malankara Church as a part of the Oriental Orthodox Churches claims the title of the Catholicos of the East and the Holy Apostolic See of St. Thomas. The Malankara Syrian Catholic Church which evolved from the Malankara Church as a part of the Eastern Catholic Church in full communion with the Holy See
Legal status of the Holy See was clarified as the result of the Treaty of 11 February 1929, between the Holy See and Italy - the so called Lateran Treaty. (...) The Lateran Treaty marks the resumption of the formal membership, interrupted in 1871, of the Holy See in the society of states." Oppenheim goes further and denies a separate legal personality for the Vatican City State. For him, the composite of the Holy See plus the Vatican City constitutes just one international person; "see" p. 328: Kunz sharply criticized this view. For him: A separate question is whether the Holy See was a subject of