on all states. The Supreme Court of India has also recognised the customary status of the convention. Scope The Convention applies only to treaties that came after it was made and to those concluded between states and so does not govern agreements between states and international organizations or between international organizations themselves, but if any of its rules are independently binding on such organizations, they remain so. The VCLT applies to treaties between states within an intergovernmental organization. However, agreements between states and international organizations or between international organizations themselves are governed by the 1986 Vienna Convention on the Law of Treaties between States and International Organizations or Between International Organizations if it enters into force. Furthermore, in treaties between states and international organizations, the terms of the Convention still apply between the state members. The Convention does not apply to unwritten agreements. Parties to the convention As of January 2018, there are 116 state parties that have ratified the convention, and a further 15 states have signed but have not ratified the convention. In addition, the Republic of China (Taiwan), which is currently recognized by only , signed the Convention in 1970 prior to the UN General Assembly's 1971 vote to transfer China's seat to the People's Republic of China, which subsequently acceded to the convention. There are 66 UN member states that have neither signed nor ratified the convention. Vienna formula 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 organisations, 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