NEW YORK ( TheStreet) -- After European antitrust regulators iced what was a $9.5 billion merger with NYSE Euronext ( NYX), court filings released on Saturday show that Deutsche Boerse is challenging the ruling, which it called a "black day" for Europe in February.

Amid uncertainty over whether a Greek parliamentary vote would push the country closer to leaving the Eurozone, Deutsche Boerse's insistence on its ability to cut mergers underscores the imperative that some financial giants see in diversifying from Europe.

Meanwhile, NYSE Euronext's recent earnings - weighed by its European operations -- signal that it wasn't hard to move on after the European Commission's antitrust authority blocked the deal in February.

In court papers published on June 16, Deutsche Boerse challenged the analysis used to block its merger with NYSE Euronext in the EU's General Court in Luxembourg. The Frankfurt-based stock exchange and derivatives powerhouse said that regulators "failed to properly assess" divestiture plans and concessions in the merger that would eliminate antitrust concerns.

The proposed deal would have created the largest stock and derivatives exchange in Europe and one of the largest in the world. But EU antitrust authorities were concerned the deal would have concentrated 90% of the region's exchange-traded derivatives market and roughly 30% of stock trading into one company, raising competition concerns.

Now, Deutsche Boerse's insistence that the deal aids its competitiveness highlights its desire to diversify and consolidate its European earnings, as a government debt crisis and shaky banking system weigh on the region's growth.

"This is a black day for Europe and for its future competitiveness on global financial markets," said Deutsche Boerse in February when the European Commission's antitrust authority blocked the merger.

In its rejection, the European Commission called for the full divestiture of either NYSE Euronext's Liffe derivatives platform or Deutsche Borse's similar Eurex business. Those derivatives units - the two largest in Europe - were a key to the merger as both companies attempted to sell assets to quell authorities.

While NYSE Euronext also said that regulators were wrong in their analysis of the merger, it likely benefitted from walking from the deal, as the European trading volumes slow amid an escalating crisis.

Wells Fargo analyst Christopher Harris calculates that exchange volumes for May were up across all of the company's units, with the exception of Euronext. Sequentially, only NYSE Euronext's European stock trading volumes fell in May, with higher trading reported at the company's other derivatives, commodities and stock units.

"It is possible fund outflows and higher investor risk aversion could have contributed to lower European equity volumes," wrote Harris in a June 7 note.

For NYSE Euronext, a European debt crisis may even be an opportunity across the Atlantic. "After a weak start to the year that proceeded into April, accelerated fears around the European sovereign crisis appeared to drive another surge in volume in May," noted KBW analyst Niamh Alexander in a June note upgrading NYSE Euronext's 2012 earnings per share assumptions.

NYSE Euronext shareholders and analysts cheered the decision to walk away and a plan to roughly double stock buybacks to $1 billion. Meanwhile, the move may allow the company to consolidate its high exposure to Europe based trading volumes. In January, Sandler O'Neill analysts wrote in a research report that NYSE Euronext may be worth $30 a share as a standalone, if the merger were to fail.

Still, shares of NYSE Euronext have fallen since February, as the outlook on stock and derivatives trading dims amid widespread risk aversion and new regulations. Overall, NYSE Euronext shares are off nearly 8% to $24.17 in 2012 after falling 12% in 2011.

"We believe the key to share price outperformance lies in unlocking the stand-alone earnings power of the franchise," wrote Credit Suisse analyst Howard Chen, in a note assessing NYSE's lackluster first quarter earnings. "While efforts to streamline costs and improve efficiency are ongoing, the headwinds of dampened activity levels--particularly within European interest rate futures--and competitive headwinds continue to take their toll on top-line revenue trends."

Deutsche Boerse's continued contest of its NYSE merger blockage is an attempt to undo key headwinds. The move challenges the legal reasoning of EU and will do little to revive the proposed merger; however, its insistence to cut mergers highlights the company's hope to move from Europe as regulators weigh on M&A. In its appeal, Deutsche Boerse insists that analysis of efficiencies, customer benefits and divestitures in the deal -- which led to an anticompetitive finding - were done incorrectly.

In the past two years, Bloomberg calculates that regulators have blocked $37 billion in exchanges deals.

Now analysts expect deals to be done, but at a much smaller size. "Scale remains a competitive advantage for exchanges, however going forward we expect management teams are more likely to drive new operating leverage through smaller niche acquisitions that complement existing Product/ technology portfolios rather than transformational M&A to build global footprint across borders," wrote Goldman Sachs analyst Daniel Harris in February.

To be seen is whether deals will reemerge after a frenetic 2011. Last week Hong Kong Exchanges and Clearing bought the London Metal Exchange for over $2 billion.

Alexander of KBW highlights that GFI Group ( GFIG), Investment Technology Group ( ITG), Interactive Brokers ( IBKR ) and MarketAxess ( MKTX ) could benefit from consolidation in the space, in a June note to clients.

-- Written by Antoine Gara in New York