NEW YORK (MarketWatch) -- NYSE Euronext NYX 0.00% and Deutsche Boerse AG /zigman2/quotes/205502669/delayed DE:DB1 +1.44% /zigman2/quotes/203431168/composite DBOEY +1.48% said Thursday they're formally ending their merger deal after the tie-up was blocked by the European Commission. The move comes nearly a year after the two financial markets signed thier combination agreement on Feb. 15, 2011.








