Signature, ratification and accession International treaties and
conventions contain rules about what entities could
sign,
ratify or
accede to them. Some treaties are restricted to states that are
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 negotiating states (most or all of which usually end up becoming the founding signatories) is that the treaty is not restricted to particular
states and so a wording like "this treaty is open for signature to
States willing to accept its provisions" is used (the "
all states formula"). In the case of regional organizations, such as the
Council of Europe or the
Organization of American States, the set of negotiating states that once agreed upon may sign and ratify the treaty is usually limited to its own member states, and non-member states may accede to it later. However, sometimes a specific set of non-member states or non-state actors may be invited to join negotiations. For example, the Council of Europe invited the "non-member States"
Canada, the
Holy See (
Vatican City),
Japan,
Mexico and the
United States to "participate in the elaboration" of the
2011 Istanbul Convention and specifically allowed the
European Union (described as an "International Organisation", rather than a "State") to sign and ratify the convention, rather than accede to it, and "other non-member States" were allowed only accession. The act of signing and ratifying a treaty as a negotiating state has the same effect as the act of acceding to a treaty (or "acceding a treaty") by a state that was not involved in its negotiation. Usually, accessions occur only after the treaty has entered into force, but the UN Secretary-General has occasionally accepted accessions even before a treaty went into force. 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 that appeared otherwise to be States could not be admitted to the United Nations or become Parties to the Statute of the International Court of Justice because of the opposition for political reasons of a
permanent member of the Security Council or have not applied for ICJ or UN membership. Since that difficulty did not arise as concerns membership in
the specialized agencies, on which there is no "veto" procedure, a number of those States became members of specialized agencies and so were in essence recognized as States by the
international community. Accordingly, to allow for as wide a participation as possible, several conventions then provided that they were also open for participation to state members of specialized agencies. The type of
entry-into-force clause used in the Vienna Convention on the Law of Treaties was later called the "
Vienna formula", and various treaties, conventions and
organizations used its wording. Some treaties that use 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. ==Interpretation of treaties==