The shares of NYSE Euronext, the world's largest listed exchange group, began trading Wednesday in Paris and New York.

The debut of NYSE Euronext follows a merger of the New York Stock Exchange (NYSE) Group, Inc. and Euronext N.V., which brings together six cash equities exchanges in five countries and six derivatives exchanges.

"NYSE Euronext is the global leader and we have significant business opportunities ahead of us. We have 78 of top 100 largest companies in the world listed on NYSE Euronext markets, and we will continue to expand our global footprint and offer our customers a wider variety of trading products and services," said John A. Thain, Chief Executive Officer of NYSE Euronext.

NYSE Group, Inc., a wholly owned subsidiary of NYSE Euronext, operates two securities exchanges, the New York Stock Exchange LLC and NYSE Arca, Inc. (formerly known as the Pacific Exchange).

Euronext is the largest central order book cash market in Europe and the second largest derivatives exchange in the world, by value of business traded.