ATEL Ventures announced that Defense.net was acquired by F5 Networks for an unspecified amount. The acquisition will bolster F5’s internet security technology and products.

As an early venture lender to Defense.net, the ATEL Funds provided the company with an asset collateralized loan. As part of the loan terms ATEL was also provided warrants that are exercisable to purchase shares of Defense.net.

“This landmark year is shaping up to be one of ATEL Venture’s best,” said Steve Rea, executive vice president at ATEL. “The consistent due diligence and investment philosophy we have at ATEL are providing significant returns to the ATEL Funds as many of our portfolio companies are experiencing exit events. ATEL is proud to partner with Defense.net and is confident that its acquisition will help improve our security over the internet.”

Belmont, CA-based Defense.net is a developer of a cloud-based defense system to prevent distributed denial of service (DDoS) attacks from shutting down online sites.