Institutional seats of the European Union are based in Luxembourg City along with the European Investment Bank. The Economic and Social Committee and the Committee of the Regions are entirely based in Brussels while the European Central Bank is based in Frankfurt and Europol is the only agency to have its seat fixed by the treaties, in The Hague. Separately, the Treaty of Nice establishes Brussels as the venue for all formal summits of the European Council after 2004. However some extraordinary sessions are sometimes held outside the city. The European Council's seat is however fixed by a declaration rather than a protocol, meaning it is
European Central Bank ECB has shareholders and stock capital. Its capital is €11 billion held by the national central banks of the member states as shareholders. The initial capital allocation key was determined in 1998 on the basis of the states' population and GDP, but the capital key has been adjusted. Shares in the ECB are not transferable and cannot be used as collateral. The European Central Bank is the "de facto" successor of the European Monetary Institute (EMI). The EMI was established at the start of the second stage of the EU's Economic and Monetary Union (EMU) to handle the transitional issues