Deutsche Boerse AG said Wednesday that it received a statement of objections against its planned merger with NYSE Euronext from the European Union's competition watchdog.
The operator of the Frankfurt stock exchange said that it regarded the statement as a "normal step" that "does not prejudge the final outcome of the case."
The statement sets out competition issues with the merger that the parties can offer to remedy, for instance by opening certain services to competitors or selling off businesses.
Deutsche Boerse said that the two exchanges were still working to "complete the transaction by the end of this year." A spokeswoman for the exchange declined to comment further on the statement of objections.
Deutsche Boerse said in February that it would buy NYSE Euronext for $10 billion, creating the world's largest exchange operator. NYSE Euronext owns bourses in Paris, Lisbon, Brussels and Amsterdam, in addition to New York.
The combination of the two exchanges has been harshly criticized by competitors like the London Stock Exchange and U.S.-based Nasdaq.
The biggest points of contention is the combined company's strong position in the trading of derivatives, a very lucrative business for exchanges. Derivatives are complicated financial products that allow investors to bet on developments in things like commodity prices or interest rates.
Trading of commodities has grown exponentially over the past decade and both Deutsche Boerse with its Eurex trading platform and NYSE's Liffe have carved out big slices of that market. Once combined, they would be by far the largest derivatives exchange in Europe.
In a speech last month, the EU's Competition Commissioner Joaquin Almunia said that that was also the focus of concerns for the Commission.
"In this particular case, we are concerned that a very large player may monopolize the derivatives markets in Europe," Almunia said. "Therefore, any outcome that would eliminate the possibility of new entry and user flexibility would be unacceptable to us."
Deutsche Boerse and NYSE, however, argue that the vast majority of derivatives are not traded on regulated exchanges but bilaterally between banks and other traders, thus providing alternatives for investors.
Melissa Eddy in Berlin contributed to this report.