Press Release

ON24 Closes Over $8 Million in Financing

Global Leader in Webcasting and Virtual Events Solutions Experiences Strong Customer and Sales Momentum

San Francisco, CA – July 15, 2008 – ON24, Inc. (http://www.ON24.com), the global leader in webcasting and virtual events solutions, announced that it has secured over $8 million in equity and expansion capital financing. U.S. Venture Partners, Canaan Partners, and Rho Ventures led the equity round; while Gold Hill Capital led the expansion capital financing. This brings ON24's total capital raised to more than $46 million. The funds will be used to accelerate ON24's global expansion of the sales, marketing and client services organizations; and product development initiatives, including ON24 Virtual Show and the company's flagship webcasting platform.

ON24 continues to experience strong customer and sales momentum, with over 40% sales growth year over year. Enterprises, business-to-business publishers, government, and life science organizations worldwide overwhelmingly select ON24 for their demand generation and corporate communications needs. With the introduction of ON24 Virtual Show on June 30, 2008, ON24 is the only company to provide an integrated family of webcasting and virtual events solutions, which streamline how organizations plan, produce and deliver cost-effective online events. This includes virtual trade shows, conferences, job fairs, and partner and customer summits.

"Our customers are experiencing increased ROI as a result of using ON24 solutions for demand generation and corporate communications. With rising fuel costs and the economic downturn, we have seen increased demand by organizations to leverage our solutions to hold online events as a cost-effective alternative to in-person events," said Sharat Sharan, president and CEO of ON24, Inc. "We've raised this funding to accelerate our growth while being well capitalized during the economic downturn."

"Our increased investment in ON24 demonstrates our confidence that they will continue to demonstrate their industry leadership with innovative solutions, high customer satisfaction, and robust sales momentum," said Deepak Kamra, general partner, Canaan Partners. "And with the introduction of their Virtual Show solution, ON24 is positioned well to be the dominant player in the online events space."

About ON24, Inc.
ON24, Inc. (http://www.ON24.com) is the global leader of webcasting and virtual events solutions for demand generation and corporate communications. ON24 provides the most reliable and trusted solutions that enable organizations to plan, produce and deliver cost-effective online events, including lead generation webinars, virtual shows, internal communications, continuing professional education and executive announcements.

More than 700 global organizations in publishing, technology, life sciences, government, and financial services rely on ON24, including Business Objects, Cardinal Health, Cisco Systems, United Business Media, Credit Suisse, U.S. Department of Education, GE Healthcare, IBM, Motorola, National Science Foundation, and Samsung. ON24 is headquartered in San Francisco, with offices in Washington, D.C., New York, London and Beijing.

"Insight24^®" - your B2B rich media network for information, intelligence and insight - is a trademark of ON24, Inc.

About Canaan Partners
Canaan Partners invests in visionary entrepreneurs and provides them the networks, insights and operational guidance required to build high-performance technology and healthcare companies. For 20 years, we have taken an active and committed role in the companies in which we invest, and have completed more than 69 mergers and acquisitions and 52 IPOs. With $3 billion under management and a worldwide footprint, the firm's technology team is committed to catalyzing the growth of innovative companies in the digital media, communications + mobility, enterprise and clean tech industries. Among our successes are DoubleClick, the leading online advertising solution, Match.com, the most popular online dating site in the world, CommerceOne, the company that pioneered and brought B2B ecommerce to the masses; Capstone Turbine, first to market and world's leading producer of commercially viable microturbine energy products; and VOIP equipment supplier Acme Packet, which was one of the top ten performing IPOs of 2006. Other Canaan technology investments include SuccessFactors, Active Networks, Blurb, Dexterra, Tremor Media and GroundWorks. Canaan has offices in California, Connecticut, India and Israel. For more information visit www.canaan.com.