The move, announced on Friday, represents an intense bidding war for NYSE Euronext, whose derivatives trading operations are highly valuable.
The new bid could also sit better politically, because the idea of a German company taking over the emblematic NYSE headquarters had stirred some political opposition in the United States.
The offer is valued at $42.50 per share, a premium of 19 percent to the agreement proposed by Deutsche Boerse
Shares of NYSE Euronext were up 11.6 percent at $39.26 in trading before the market opened.
(Reporting by Supantha Mukherjee in Bangalore and Lauren Tara LaCapra in New York; Editing by Unnikrishnan Nair and Lisa Von Ahn)