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 The NCBs are the sole subscribers to and holders of the capital of the ECB. Today, ECB capital is about €11 billion, which is held by the national central banks of the member states as shareholders. The NCBs’ shares in this capital are calculated using a capital key which reflects the respective member’s share in the total population and gross domestic product of the EU. The ECB adjusts the shares every five years and whenever a new country joins the EU. The adjustment is made on the basis of data provided by the European Commission. All national central banks (NCBs)