Vienna Convention On The Law of Treaties - Vienna Formula

Vienna Formula

International treaties and conventions contain rules about what entities could sign, ratify or accede to them. Some treaties are restricted to states members of the UN or parties to the Statute of the International Court of Justice. In rare cases there is an explicit list of the entities that the treaty is restricted to. More commonly the aim of the founding signatories is that the treaty is not restricted to particular states only and so a wording like "this treaty is open for signature to States willing to accept its provisions" is used (the so-called "All States formula").

When a treaty is open to "States", for the depositary authority it is difficult or impossible to determine which entities are States. If the treaty is restricted to Members of the United Nations or Parties to the Statute of the International Court of Justice, there is no ambiguity. However, a difficulty has occurred as to possible participation in treaties when entities which appeared otherwise to be States could not be admitted to the United Nations, nor become Parties to the Statute of the International Court of Justice owing to the opposition, for political reasons, of a permanent member of the Security Council or haven't applied for ICJ or UN membership. Since that difficulty did not arise as concerns membership in the specialized agencies, where there is no "veto" procedure, a number of those States became members of specialized agencies, and as such were in essence recognized as States by the international community. Accordingly, and in order to allow for as wide a participation as possible, a number of conventions then provided that they were also open for participation to States members of specialized agencies. The type of entry-into-force clause utilized in the Vienna Convention on the Law of Treaties was later called the "Vienna formula" and its wording was utilized by various treaties, conventions and organizations.

Some treaties that utilize it include provisions that in addition to these States any other State invited by a specified authority or organization (commonly the United Nations General Assembly or an institution created by the treaty in question) can also participate, thus making the scope of potential signatories even broader.

The present Convention shall be open for signature by all States Members of the United Nations or of any of the specialized agencies or of the International Atomic Energy Agency or parties to the Statute of the International Court of Justice, and by any other State invited by the General Assembly of the United Nations to become a party to the Convention, as follows: until 30 November 1969, at the Federal Ministry for Foreign Affairs of the Republic of Austria, and subsequently, until 30 April 1970, at United Nations Headquarters, New York.

— Vienna Convention on the Law of Treaties, Article 81, Signature