The any-state formula is a drafting convention in multilateral treaties that specifies which states may sign, ratify, or accede. Under this formulation, participation is open to any state, with no requirement of UN membership, ICJ statute adherence, or invitation by depositary. It contrasts with three other common formulas: the Vienna formula (open to UN members, specialized agency members, ICJ Statute parties, and states invited by the General Assembly), the all-states formula (functionally similar but politically charged), and restricted formulas limiting accession to regional or thematic groupings.
The choice of formula carries significant political weight because it determines whether entities of contested statehood—such as Palestine, Kosovo, the Cook Islands, or Taiwan—can join. Depositaries, often the UN Secretary-General, historically resisted the any-state formula because it forced them to adjudicate statehood claims. To resolve this, the General Assembly adopted guidance directing the Secretary-General to follow the practice of the Assembly itself when uncertainty arises, effectively channeling disputes back to the political organ.
The any-state formula appears in several disarmament and humanitarian instruments where universality is prioritized over political gatekeeping. Negotiators advocating broad participation—particularly for treaties aiming at global norms like nuclear non-proliferation or landmine bans—often push for this formula, while states wishing to exclude rivals lobby for the Vienna formula or named-state lists.
For practitioners, identifying the participation clause is a first step in assessing a treaty's universality ambitions and its political backers. The clause typically appears near the end of the instrument, often titled Signature, Ratification, or Accession.
Example
Negotiators of the 2017 Treaty on the Prohibition of Nuclear Weapons used an any-state formula to maximize accession potential, including by entities not universally recognized as UN members.