X0304 4/A 2011-02-04 2011-02-08 0 0001048695 F5 NETWORKS INC FFIV 0001105033 CHRISTIANSON JEFFREY A C/O F5 NETWORKS, INC. 401 ELLIOTT AVE. WEST SEATTLE WA 98119 0 1 0 0 EVP and General Counsel Common Stock 2011-02-04 4 S 0 2134 120.15 D 6439 D Sale pursuant to the terms of a 10b5-1 trading plan. Because of an administrative error, the reporting person's original Form 4 over-reported by 100 shares the sale of securities, and underreported by 100 shares the amount of securities beneficially owned following the reported transaction. These 100 shares were also omitted from the holdings included in Form 4 reports subsequently filed by the reporting person. /s/ Jeffrey A. Christianson 2012-02-10