The stock exchanges of Paris, Amsterdam, and Brussels have signed an agreement to merge in September, creating Europe's second-largest equities exchange after London. More than 1,300 companies will be listed on the new exchange, which has been christened "Euronext," representing 2.38 trillion euros (US$2.38 trillion) in market capitalization. Euronext will be Europe's biggest market for options on shares and European indices and will be registered in the Netherlands. Euronext is open to other partners under the framework of previous agreements among eight European exchanges. Luxembourg already has expressed its intention to join. Others to join may include London, Frankfurt, the Swiss Exchange, Madrid, and Milan.