SOURCEFIRE NAMED TO LIST OF TOP 100 PRIVATE COMPANIES FOR THIRD CONSECUTIVE YEAR

AlwaysOn's Top 100 Private Companies Award Recognizes Sourcefire's Growth and Innovation

Columbia, MD-- July 13, 2006 -- Open source innovator, Sourcefire, Inc., the world leader in network intrusion prevention, today announced that it has been chosen by AlwaysOn as one of the Top 100 Private Company award winners for the third straight year. Sourcefire was handpicked by the AlwaysOn editorial panel based on a set of five criteria - technology innovation, market potential, customer adoption, media buzz and investor value creation.

Sourcefire will be honored at the AO2006: Stanford Summit, which takes place July 25-27, 2006 in Palo Alto, California. This executive forum attracts successful entrepreneurs, business and political thought leaders, top venture capitalists. The AO100 consists of private companies at all stages of development, from early to late stage, and was selected from over 1,000 companies, nominated by leading venture capitalists, investment bankers and industry analysts.

“As the largest privately-held vendor in our market, Sourcefire is changing the way companies approach their network security,” said Tom McDonough, President and COO of Sourcefire. “Being selected as an AlwaysOn Top 100 Private Company Award for a third time not only validates our growth but also highlights the innovation that we are delivering to market.”

Sourcefire is widely considered one of the most innovative firms in the security industry, garnering more than 18 awards for its technology and business success since the beginning of 2005. In December 2005, Sourcefire was named to the Leaders Quadrant of the Gartner Magic Quadrant for Network Intrusion Prevention System Appliances, 2H05 report. Since the beginning of the year, the Sourcefire 3D System received top honors at the annual SC Magazine Awards, being named the Best Security Solution in the U.S., and was recognized as the “Security Product of the Year” at the European NetEvents “Technology Leader” Awards. Sourcefire's technology was also named Best of the Best in the May issue of Redmond Magazine.

“The AO100 companies are driving the next wave of innovative technologies that are disrupting the old guard and shaping the new media landscape,” said Tony Perkins, founder of AlwaysOn. “As ever, we were inundated with nominations from leading companies, and it’s heartening to know that tomorrow’s thought leaders and technology visionaries are already out there. My congratulations to each AO100 winner - these are the companies which we predict will have the greatest market traction, strongest innovation and most game-changing approaches this year.”

About AlwaysOn
AlwaysOn is transforming the communication business with its online blogging network; establishing it as a leader in the open media revolution. Borrowing on the underground blogging and social networking traditions, AlwaysOn (www.alwayson-network.com) was launched in 2003. Today, AlwaysOn’s annual Summit @ Stanford and OnHollywood events, print “blogozine” and online services encourage direct collaboration between the global thought leaders and technology insiders whose ideas and innovations are shaping the always-on world.

AlwaysOn, LLC, is a privately held and virtually headquartered company born out of the heart of Silicon Valley.

About Sourcefire
Sourcefire, Inc., the world leader in intrusion prevention, is transforming the way organizations manage and minimize network security risks with its 3D Approach - Discover, Determine, Defend - to securing real networks in real-time. The company's ground-breaking network defense system unifies intrusion and vulnerability management technologies to provide customers with the most effective network security available. Founded in 2001 by the creator of open source Snort^®, Sourcefire is headquartered in Columbia, MD. At work in leading Fortune 1000 and government agencies, the names Sourcefire and founder Martin Roesch have grown synonymous with innovation and intelligence in network security.

In May, Sourcefire announced that the company secured $20 million in late-stage funding led by Meritech Capital Partners, a leading provider of late-stage venture capital to premier information technology companies.

For more information about Sourcefire, please visit http://www.sourcefire.com.