F5 Networks Awarded Key Patent for Its Cookie Persistence Technology.

Business Editors/High-Tech Writers

SEATTLE--(BUSINESS WIRE)--March 19, 2003

F5 Networks Files Patent Infringement Lawsuit Against

Array Networks, Netscaler, and Radware

F5 Networks Inc. (Nasdaq:FFIV), the leading provider of Application Traffic Management solutions, today announced that it has been awarded a patent for its Cookie Persistence technology.

The U.S. Patent No. 6,473,802, entitled "Method and System for Storing Load Balancing Information with an HTTP Cookie," enables key capabilities for any traffic management and load balancing product.

F5's patented Cookie Persistence technology uses an HTTP cookie stored on the customer's computer to allow the customer to reconnect to the same server previously visited at a Web site. This is important, for example, where a customer adds items to a shopping cart at a Web site, then leaves the site before completing the transaction. When the customer returns, Cookie Persistence allows a traffic management device to direct the customer to the server that has stored the customer's shopping cart information, allowing the customer to complete the transaction. Without Cookie Persistence, the traffic management device could direct the customer's request to a different server, which may not know about the customer and his shopping cart status. F5 introduced Cookie Persistence capabilities to the traffic management market in 1999.

F5 has filed a patent infringement lawsuit against Array Networks, Inc., NetScaler, Inc., and Radware, Ltd. in the U.S. District Court in Seattle. According to allegations in the complaint, all three companies are infringing upon the Cookie Persistence patent. F5 Networks is seeking permanent injunctive relief and damages for its patent infringement claim.

"We have invested millions in research and development to deliver the best traffic management products to the market," said John McAdam, President and CEO of F5 Networks. "Cookie Persistence is no longer just a consideration in planning and designing Web site servers, it is a critical capability and we have incorporated this functionality into all our BIG-IP products. Although F5 does not like to resort to litigation, it cannot allow the unauthorized use of its intellectual property."

About F5 Networks

F5 Networks is the industry leader in Application Traffic Management, enabling enterprises and service providers to optimize any mission-critical application or Web service, providing secure and predictable delivery of application traffic in an unpredictable environment. Through F5's unique open iControl(TM) API, third party applications and network devices can take an active role in shaping network traffic, delivering application aware networks that allow customers to direct traffic based on their exact business requirements. Our solutions optimize the availability, security and speed of mission-critical servers and applications, including enterprise applications, Web services, mobile IP applications, Web publishing, content delivery, e-commerce, caching, firewalls and more. F5's solutions are widely deployed in large enterprises, the top service providers, financial institutions, government agencies, healthcare, and portals throughout the world. The company is headquartered in Seattle, Washington, and has offices throughout North America, Europe Japan and Asia Pacific. F5 Networks is located on the Web at www.f5.com.

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