News Release

TMX Group Acquires Atrium Network™

August 3, 2011

Acquisition accelerates expansion of TMX Group's data network into Europe and the U.S.

August 3, 2011 (TORONTO) - TMX Group Inc., Canada's leading operator of exchanges and related services, today announced that it has acquired Atrium Network, a leading provider of high availability, cost effective, low latency network solutions in Europe and North America. Atrium Network, which will be rebranded TMX Atrium, will operate as a unit of TMX Datalinx™, TMX Group's information services division.

Both Atrium Network and TMX Datalinx provide capital markets data and connectivity solutions to the global financial services community. Atrium Network's existing North American, European and trans-Atlantic connectivity platform covers the service areas that TMX Datalinx planned to build out with its TMXnet™ network. In early 2011, TMX Datalinx introduced TMXnet, and in June 2011, the TMXnet network was expanded into key U.S. financial centres.

"Atrium Network extends our connectivity solutions into Europe and expands our U.S. presence significantly ahead of schedule," said Eric Sinclair, President, TMX Datalinx and Group Head of Information Services. "We are very excited about the opportunity TMX Atrium presents. Our combined network will offer 25 points of presence in 11 countries, 24 trading venues and 300 data sources with plans to expand in the future where our clients need us."

The combined connectivity and access points offer even greater value to current TMX Datalinx clients while increasing opportunities to offer capital markets connectivity solutions to a much broader audience. Atrium Network clients will benefit from TMX Datalinx's global content strategy as well as its plans to provide access to all key marketplaces. The acquisition also enables the company to add additional content from market centres in Europe and North America.

"This is an important development for our companies and for our respective clients," added Emmanuel Carjat, Chief Executive Officer of Atrium Network. "The complementary capabilities offered by Atrium Network and TMX Datalinx will enable our current and future clients to benefit significantly from additional data content and from enhanced access to trading solutions. TMX Atrium will continue to provide a neutral platform to facilitate communication within the global financial markets."

The global connectivity footprint that Atrium Network offers will also provide a new channel for order flow into Toronto Stock Exchange, TSX Venture Exchange and Montreal Exchange.

The terms of the agreement are not material. Atrium Network employs 21 people, most of whom are based in London.

About TMX Group (TSX-X)

TMX Group's key subsidiaries operate cash and derivative markets for multiple asset classes including equities, fixed income and energy. Toronto Stock Exchange, TSX Venture Exchange, Montreal Exchange, Canadian Derivatives Clearing Corporation, Natural Gas Exchange, Boston Options Exchange (BOX), Shorcan, Shorcan Energy, Equicom and other TMX Group companies provide listing markets, trading markets, clearing facilities, data products and other services to the global financial community. TMX Group is headquartered in Toronto and operates offices across Canada (Montreal, Calgary and Vancouver), in key U.S. markets (Houston, Boston and Chicago) as well as in London. For more information about TMX Group, visit our website at www.tmx.com.

About Atrium Network

Atrium Network™ provides smarter connectivity solutions for the financial community.

Atrium Network offers client and industry connectivity via its extranet services (a single point of access to exchanges, MTFs, ECNs, clearing houses, CSDs, brokers and market data providers), as well as corporate technology (internet and intranet solutions). With a focus on reducing complexity and improving operational excellence, Atrium Network provides a range of innovative access options and the ability to self-provision.

Atrium Network is the market leader in providing an ultra-low latency connectivity solution to multiple trading venues. Their 'Exchange Ring' offers a fabric of dark fibre connectivity to each of the main liquidity venues and is designed to mitigate the risk of any unnecessary co-location investment and ensure lowest possible latency access to all available trading venues.

In September 2009 Atrium Network was awarded 'Best New Vendor' at Financial News' European Awards for IT Excellence and in November 2009, was recognised as a leading innovator by Financial News in its annual Tech21 list of technology firms.

Atrium Network currently has a presence in Europe, North America and South America. Atrium Network is headquartered in Luxembourg with offices in London, New York and Paris. For more information, please view Atrium Network's website at www.atriumnetwork.com.

For more information please contact:

Carolyn Quick
Director, Corporate Communications
416-947-4597
carolyn.quick@tmx.com

Julia Streets/Holly Finn
Streets Consulting Ltd
Julia.streets@streetsconsulting.com / holly.finn@streetsconsulting.com
+ 44 (0)20 7959 2235