* No firm date set for board to consider counterbid-source
* Nasdaq's $11.3 bln offer meant to trump Deutsche Boerse (Adds possible board decisions, background on bid)
NEW YORK, April 5 (Reuters) - NYSE Euronext's board of directors plans to meet by April 14 to consider Nasdaq OMX Group's unsolicited takeover bid, though no firm date has been set, a person familiar with the plan said on Tuesday.
On Friday, Nasdaq partnered with U.S.-based IntercontinentalExchange Inc to make an $11.3-billion offer for the Big Board parent, an attempt to thwart a friendly $10.2-billion takeover offer from Germany's Deutsche Boerse.
The counterbid would bring together fierce U.S. rivals Nasdaq and NYSE and hand the target company's profitable derivatives business to ICE, revamping ownership of the world's capital markets as a merger frenzy takes hold.
NYSE's board has a few main options: determine Nasdaq's bid is "superior" to that of Deutsche Boerse; reject it as inferior; or request more information from Nasdaq and ICE.
NYSE Euronext said on Friday its board would "carefully review" the new offer and urged shareholders not to take any action pending its review. The company's shares are up 10.7 percent since the new bid was announced. (Reporting by Jonathan Spicer, editing by Gerald E. McCormick and Maureen Bavdek)