X0306 4 2012-10-30 0 0001048695 F5 NETWORKS INC FFIV 0001200474 TRIEBES KARL D C/O F5 NETWORKS, INC. 401 ELLIOTT AVE. WEST SEATTLE WA 98119 0 1 0 0 EVP, Product Development & CTO Common Stock 2012-10-30 4 A 0 1782 0.00 A 7428 D Common Stock 2012-11-01 4 M 0 1790 0.00 A 9218 D Restricted Stock Units 0.00 2012-11-01 4 M 0 720 0.00 D Common Stock 720 12159 D Restricted Stock Units 0.00 2012-11-01 4 M 0 676 0.00 D Common Stock 676 4734 D Restricted Stock Units 0.00 2012-11-01 4 M 0 394 0.00 D Common Stock 394 3152 D Restricted Stock Units 0.00 2012-10-30 4 A 0 15285 0.00 A Common Stock 15285 15285 D Shares acquired based on performance targets for the August 2, 2010, August 1, 2011, and November 9, 2011 awards of Restricted Stock Units. Shares acquired upon vesting of the August 2, 2010, August 1, 2011, and November 9, 2011 awards of service-based Restricted Stock Units. Each Restricted Stock Unit represents a contingent right to receive one share of F5 Networks, Inc. Common Stock on the vest date. 8,635 of the service-based Restricted Stock Units awarded August 2, 2010 vest in twelve equal quarterly increments beginning November 1, 2010; an additional 10,000 Restricted Stock Units vest August 1, 2013. If the reporting person continues to serve as an officer of the Company on the vest date, the corresponding number of shares of Common Stock of F5 Networks, Inc. will be issued to the reporting person on the vest date. The August 1, 2011 award of service-based Restricted Stock Units vests in twelve equal quarterly increments beginning November 1, 2011. The November 9, 2011 award of service-based Restricted Stock Units vests in twelve equal quarterly increments beginning February 1, 2012. Concurrent with this award of service-based Restricted Stock Units, the Company granted the reporting person additional Restricted Stock Units that vest based on performance targets ("Performance RSUs"). If the performance targets are achieved at 100%, the reporting person will receive 15,285 Performance RSUs over the four-year vesting period; the actual number of Performance RSUs received may be more or less depending on whether and to the extent that performance is greater than or less than targets. Performance RSUs are not reported in Table II; the underlying shares of Performance RSUs will be reported in Table I if and when the Compensation Committee of the Board of Directors determines that the performance targets have been achieved. The November 1, 2012 award of service-based Restricted Stock Units vests in sixteen equal quarterly increments beginning February 1, 2013. /s/ Jeffrey A. Christianson by Power of Attorney 2012-11-01