Euronext shareholders gave the pan-European exchange operator freedom to seek a better offer from the New York Stock Exchange and Deutsche Boerse after rejecting their proposals.
Shareholders at Euronext's annual general meeting held in Amsterdam said they felt both rival proposals undervalued the exchange, which operates Paris, Amsterdam, Brussels and Lisbon bourses, and London's Euronext.liffe derivatives exchange.
NYSE unveiled its stock and cash offer of around €8 billion for Euronext, while Deutsche Boerse detailed a cash-and-share bid today valuing Euronext at €8.6 billion, at yesterday's closing prices.
Euronext said at the meeting the Deutsche Boerse proposal was basically the same as the offer made at the weekend.
The Frankfurt-based exchange holds its shareholder meeting tomorrow, at which it said it will "provide an important input" to its review of the implications of Euronext's AGM.
The shareholder vote on the principle of a merger with Deutsche Boerse showed 43.9 million shares against and 30.6 million for a tie-up. The NYSE proposal, having only been unveiled on Monday, was not on the formal agenda.