NYSE Euronext (NYX) announced it will acquire Nyfix Inc. (NYFX) for $144 million, broadening the transatlantic exchange operator's push into the technology underpinning financial markets in the U.S.

The price tag, which includes preferred stock, bolsters NYSE Euronext's stable of technology services and provides access to Nyfix's pre-trade order processing community, covering more than 1,000 sell-side and buy-side participants.

Nyfix shares will be purchased for $1.675 each, a 95% premium to Wednesday's closing price. The stock, which traded above $45 in 2000 and was down 74% the past year through Wednesday.

NYSE Euronext shares were 1.7% lower at $28.31 in recent trading Thursday.

Shares of Nyfix shot up 90% to $1.63.

Nyfix, a provider of brokerage services and trade stations, facilitates pre-trade communication between sell-side brokers and the pension funds and asset managers they serve.

Plugging into that conversation will expand the potential client base for NYSE Euronext's stable of market data, trading and connectivity services, particularly on the buy-side.

The deal comes as the New York-based exchange company constructs a new trading hub in New Jersey to facilitate high-speed trading. NYSE Euronext looks to recruit Nyfix customers for the venture, boosting trade execution times by co-locating clients' trading systems and algorithms inside the data center.

"This is an extension of NYSE Euronext as a technology company, and represents our diversification into a broader community than just trade execution," said Stanley Young, chief executive of NYSE Technologies and co-chief information officer at NYSE Euronext, who will oversee the Nyfix unit.

Euronext's core cash equities business, along with that of chief rival Nasdaq OMX Group Inc. (NDAQ), has come under pressure in the past 18 months from smaller electronic rivals BATS Exchange and Direct Edge, which together command a quarter of the U.S. market.

New York-based Nyfix, founded in 1991, has about 250 full-time employees. Bob Moitoso, global head of the FIX Division at Nyfix, will stay on and report to Young; Chief Executive P. Howard Edelstein will depart upon completion of the transaction, expected in the fourth quarter.

Nyfix also operates the Millennium dark pool, an alternative trading system that facilitates anonymous electronic trading of large stock orders.

NYSE Euronext will look to sell that platform around the close of the transaction, according to officials.

The acquisition is expected to add to NYSE Euronext's 2010 earnings, excluding one-time costs, with further cost savings and tax benefits expected.

NYSE Euronext has made a major push on the technology front this year as it develops new services and updates aging systems.

The company on July 1 announced order-execution times had been slashed 20-fold at the NYSE with the implementation of the new NYSE Super Display Book system for processing orders. However, NYSE Euronext is still seen lagging rival exchanges with faster systems.

Ever-faster order execution is a key factor for many traders, especially as automated trading grabs an increasing amount of overall trading volume.

-By Kevin Kingsbury, Dow Jones Newswires; 212-416-2354; kevin.kingsbury@dowjones.com; and Jacob Bunge, Dow Jones Newswires; (312) 750-4117; jacob.bunge@dowjones.com