SOURCEFIRE SELECTED BY ALWAYSON AS TOP 100 PRIVATE COMPANY AWARD WINNER

Latest Award Recognizes Sourcefire’s Innovation, Market Potential and Value Creation for Second Year in a Row

Columbia, MD, June 29, 2005 - Sourcefire, Inc., the world leader in intrusion prevention, today announced that it has been chosen by AlwaysOn as one of the Top 100 Private Company award winners.Sourcefire was handpicked by the AlwaysOn editorial team based on a set of five criteria – innovation, market potential, customer adoption, media buzz and investor value creation.

The AO 100 was selected from over 1,000 companies, peer-nominated by leading venture capitalists, investment bankers and industry analysts. The AO 100 consists of private companies at all stages of development, from early to late stage.

The Sourcefire 3D System offers the most flexible and precise intrusion prevention and network discovery technologies worldwide. Sourcefire’s 3D Approach – Discover, Determine, Defend – to securing real networks in real-time provides proactive defense-in-depth through an integrated process of discovering risks, vulnerabilities and threats; determining their business impact; and taking the appropriate action to defend the network.

“The AO 100 companies are shaping today’s web-driven, connected environment,” said Tony Perkins, founder and editor of AlwaysOn. “We were inundated with nominations from leading companies, many of which I hope will appear on our list next year. My congratulations to each AO 100 winner – these are the companies which we predict will have the greatest market traction, strongest innovation and most game-changing approaches this year.”

“As an AlwaysOn Top 100 Private Company award winner two years in a row, Sourcefire is proud of the advancements we have made with the company and our technology in the last 12 months,” said Wayne Jackson, CEO of Sourcefire. “As the fastest growing security company in the United States and the largest privately-held intrusion prevention vendor, Sourcefire is being recognized by customers and industry influencers as the next generation provider of increased network security. This award is the latest validation for Sourcefire’s innovation and market traction.”

Sourcefire has received significant company and technology recognition throughout 2005. Earlier this year Sourcefire was named Frost and Sullivan’s “Security Company of the Year” and the Most Innovative Company at the RSA Conference. In addition, the Sourcefire 3D System received “NSS Approved” certification in March, and in April Sourcefire RNA became only the fifth product in history to receive “NSS Gold” for its unique ability to solve customers’ security issues.

The AO 100 will be honored at the AO2005: Innovation Summit at a VIP reception at 5.00pm on July 19, 2005 at the Frances C. Arrillaga Alumni Center on the Stanford University campus in Palo Alto, California.

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 Snort, Sourcefire is headquartered in Columbia, MD and has received numerous accolades including being named the Frost & Sullivan 2005 Network Security Infrastructure Protection Company of the Year. 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. For more information about Sourcefire, please visit www.sourcefire.com.

About AlwaysOn
AlwaysOn is transforming the communication business with its online blogging network, establishing it as a leader in the Open Media revolution. Borrowing from the underground traditions of blogging and social networking, AlwaysOn (http://www.alwayson-network.com/) was launched in 2003. Today, AO’s annual Summit @ Stanford and OnHollywood events, print “blogozine” and online services encourage direct collaboration between global thought leaders and technology insiders. No other media brand has dared allow such openness amongst its readers and participants. AlwaysOn, LLC, is a privately held and virtually headquartered company born out of the heart of Silicon Valley.