Your cooperation is appreciated, since a majority of the shares of common stock must be represented, either in person or by proxy, to constitute a quorum for the conduct of business.

F5 Networks, Inc. (the “Company”) is furnishing this Proxy Statement and the enclosed proxy in connection with the solicitation of proxies by the Board of Directors of the Company for use at the Annual Meetingannual meeting of Shareholdersshareholders to be held on March 22, 2007,11, 2008, at 10:11:00 am,a.m., Pacific Standard Timetime at F5 Networks, Inc., 401 Elliott Avenue West, Seattle, Washington 98119, and at any adjournments thereof (the “Annual Meeting”). These materials are being mailed to shareholders on or about February 2, 2007.January 25, 2008. The Company’s principal executive offices are located at 401 Elliott Avenue West, Seattle, Washington 98119. The Company’s telephone number at that location is206-272-5555.

Only holders of the Company’s common stock, no par value (the “Common Stock”), as of the close of business on January 16, 20077, 2008 (the “Record Date”) are entitled to vote at the meeting.Annual Meeting. As of the Record Date, there were 41,259,73685,068,950 shares of Common Stock outstanding.

A majority of the outstanding shares of Common Stock entitled to vote at the Annual Meeting must be present in person or by proxy in order for there to be a quorum at the meeting. Shareholders of record who are present at the meeting in person or by proxy and who abstain from voting, including brokers holding customers’ shares of record who cause abstentions to be recorded at the meeting, will be included in the number of shareholders present at the meeting for purposes of determining whether a quorum is present.

Each shareholder of record is entitled to one vote at the Annual Meeting for each share of Common Stock they hold on the Record Date. Shareholders may vote their shares by using the enclosed proxy card, over the Internet or by phone. If a proxy is received that does not specify a vote or an abstention, the shares represented by that proxy will be voted: (1)voted (i) FOR the nominees to the Board of Directors listed in this Proxy Statement; (2) FOR an amendment to the 2005 Plan to increase the number of shares of common stock issuable under the 2005 Plan; (3)(ii) FOR the ratification of the selection of PricewaterhouseCoopers LLP as the Company’s independent auditor for the fiscal year ending September 30, 2007; (4) AGAINST the shareholder proposal regarding executive compensation;2008; and (5)(iii) in accordance with the discretion of the named proxyproxies on any other matters properly brought before the Annual Meeting. The Company is not aware, as of the date hereof, of any matters to be voted upon at the Annual Meeting other than those stated in this Proxy Statement and the accompanying Notice of Annual Meeting of Shareholders. If any other matters are properly brought before the Annual Meeting, the enclosed proxy card and proxies submitted by telephone or over the Internet give discretionary authority to the person named as proxy to vote the shares represented by the proxy in his discretion.

Under Washington law and the Company’s Second Amended and Restated Articles of Incorporation and Bylaws (the “Bylaws”), if a quorum exists at the meeting, the nominees for director who receive the greatest number of votes cast will be elected to the Board of Directors. In addition, if a quorum exists at the meeting, approval of all other matters that properly come before the Annual Meeting requires that the votes cast in favor of such actions exceed the votes cast against such actions. Abstentions and “broker non-votes” (shares held by a broker or nominee that does not have the authority, either express or discretionary, to vote on a particular matter) will have no impact on the election of directors or the other proposals at the meeting since they have not been cast in favor of or against any nominee or a proposal.

A shareholder may revoke a proxy at any time before it is voted at the Annual Meeting by (a) delivering a proxy revocation or another proxy bearing a later date to the Corporate Secretary of the Company at 401 Elliott Avenue West, Seattle, Washington 98119 before or at the Annual Meeting or (b) attending the Annual Meeting and voting in person. Attendance at the Annual Meeting will not revoke a proxy unless the shareholder actually votes in person at the meeting.

The Board of Directors of the Company currently consists of seveneight directors divided into three classes. Currently, the Class I directors are Karl D. Guelich and Keith D. Grinstein; the Class II directors are Deborah L. Bevier, Alan J. Higginson and John McAdam; and the Class III directors are Rich Malone, and A. Gary Ames.Ames and Scott Thompson. Mr. Malone’s term on the Board of Directors expires on the date of the Annual Meeting. Mr. Malone will not stand for re-election at the Annual Meeting. At the Annual Meeting, the shareholders will vote on the election of threetwo Class IIIII directors to serve for three-year terms until the annual meeting of shareholders for fiscal year end 20092010 and until their successors are elected and qualified. The Class I directors will hold office until the Company’s annual meeting for fiscal year end 2008 and the Class IIIII directors will hold office until the Company’s annual meeting for fiscal year end 2007.2009. All directors will hold office until the annual meeting of shareholders at which their terms expire and the election and qualification of their successors. Promptly following the annual meeting, the Board of Directors will take such actions that are necessary to reduce the number of directors on the Board of Directors to seven members. Such actions will reduce the number of Class III directors from three to two.

The Board of Directors has nominated Deborah L. Bevier, Alan J. HigginsonA. Gary Ames for re-election and John McAdamScott Thompson for reelectionelection to the Board of Directors as Class IIIII directors at the Annual Meeting. The nominees have consented to serve as directors of the Company if elected. If any of the nominees declines to serve or becomes unavailable for any reason, or if a vacancy occurs before the election (although we know of no reason to anticipate that this will occur), the proxies may be voted for such substitute nominees as the Company may designate.

The following individuals have been nominated for election to the Board of Directors or will continue to serve on the Board of Directors after the Annual Meeting:

John McAdam, age 55,56, has served as our President, Chief Executive Officer and a director since July 2000. Prior to joining us, Mr. McAdam served as General Manager of the Web server sales business at International Business Machines Corporation from September 1999 to July 2000. From January 1995 until August 1999, Mr. McAdam served as the President and Chief Operating Officer of Sequent Computer Systems, Inc., a manufacturer of high-end open systems, which was sold to International Business Machines

Karl D. Guelich, age 64,65, has served as one of our directors since June 1999 and as board chair from January 2003 through April 2004. Mr. Guelich has been in private practice as a certified public accountant since his retirement from Ernst & Young LLP in 1993, where he served as the Area Managing Partner for the Pacific Northwest offices headquartered in Seattle from October 1986 to November 1992. Mr. Guelich holds a B.S. in Accounting from Arizona State University.

Alan J. Higginson, age 59,60, has served as board chair since April 2004, and as one of our directors since May 1996. Mr. Higginson has been theis Chairman of Hubspan, Inc., ane-business infrastructure provider. He served as President and Chief Executive Officer of Hubspan Inc., ane-business infrastructure provider, sincefrom August 2001.2001 to September 2007. From November 1995 to November 1998, Mr. Higginson served as President of Atrieva Corporation, a provider of advanced data backup and retrieval technology. Mr. Higginson holds a B.S. in Commerce and an M.B.A. from the University of Santa Clara.

Keith D. Grinstein, age 46,47, has served as one of our directors since December 1999. He also serves as board chair for Coinstar, Inc., a coin counting machine company, and as lead outside director for Nextera, Inc.

The Board of Directors has standing Audit, Compensation and Nominating and Corporate Governance Committees (collectively, the “Standing Committees”). The chartersEach of the Standing Committees has a charter, copies of which are available on our website. A copy ofwebsite atwww.f5.com under the Amended and Restated Audit Committee charter is attached to this Proxy Statement as Appendix A and is incorporated herein by reference.“About F5 — Investor Relations — Corporate Governance” section.

Audit Committee.  The Board of Directors has adopted a charter governing the duties and responsibilities of the Audit Committee. As described more fully in the charter, the functions of the Audit Committee are to select, evaluate and, if necessary, replace the Company’s independent registered public accounting firm, to review and approve the planned scope, proposed fee arrangements and results of the annual audit, approve any proposed non-audit services to be provided by the independent registered public accounting firm, oversee the adequacy of accounting and financial controls, review the independence of the auditors, and oversee the Company’s financial reporting process on behalf of the Board of Directors. The Audit Committee members have beenare Messrs. Guelich Higginson(chairman), Grinstein and Grinstein since January 2004.Malone, and Ms. Bevier. The Board of Directors has determined that Mr. Guelich is an “audit committee financial expert” as defined in Item 401(h)407 ofRegulation S-K. Each current member of the Audit Committee is, and each member of the Audit Committee during fiscal year end 20062007 was, an independent director as defined by the Nasdaq Marketplace Rules (as independence is currently defined in Rules 4200(a)(15) and 4350(d)4350(c) therein).

Compensation Committee.  The Compensation Committee’s functionCommittee conducts an annual review to determine whether the Company’s executive compensation program is to recommendmeeting the goals and objectives set by the Board of Directors. The Committee recommends for approval by the Board of Directors the compensation for the Chief Executive Officer and directors, including salaries, bonus levels and stock awards, and to reviewreviews and approves compensation proposals made by the Chief Executive Officer for the other executive officers. The

As set forth in the charter of the Audit Committee of the Board of Directors, any related person transaction involving a Company director or executive officer must be reviewed and approved by the Audit Committee. Any member of the Audit Committee who is a related person with respect to a transaction under review may not participate in the deliberations or vote on July 14, 2006)the approval or ratification of the transaction. Related persons include any director or executive officer, certain shareholders and any of their “immediate family members” (as defined by SEC regulations). To identify any related person transaction, the Company requires each director and executive officer to complete a questionnaire each year requiring disclosure of any prior or proposed transaction in which the director, executive officer or any immediate family member might have an interest. Each director and executive officer is directed to notify the Company’s Senior Vice President and General Counsel of any such transaction that arises during the year. The Company’s chief accounting officer reports to the Audit Committee on a quarterly basis regarding any potential related person transaction. In addition, the Board of Directors determines on an annual basis which directors meet the definition of independent director under the Nasdaq Marketplace Rules and reviews any director relationship that would potentially interfere with his or her exercise of independent judgment in carrying out the responsibilities of a director. A copy of the Company’s “Policy and Procedure for Approving Related-Person Transactions” is available on our website atwww.f5.com under the “About F5 - Investor Relations — Corporate Governance” section.

The Company’s Board of Directors met or acted by unanimous written consent 1711 times during fiscal 2006.2007. The Audit Committee met 13 times and the Compensation Committee met or acted by unanimous written consent 915 times. During fiscal 2006,2007, the Nominating and Corporate Governance Committee met 4 times. The outside directors met 53 times during fiscal 2006,2007, with no members of management present. Each member of the Board of Directors attended 75% or more of the Board meetings during fiscal 2006.2007. Each member of the Board of Directors who served on the Standing Committees attended at least 75% of the committee meetings.

Criteria for Nomination to the Board.  The Nominating and Corporate Governance Committee (the “Nominating Committee”) considers the appropriate balance of experience, skills and characteristics required of the Board of Directors, and seeks to insureensure that at least a majority of the directors are independent under the rules of the Nasdaq Stock Market,Marketplace Rules, that members of the Company’s audit committeeAudit Committee meet the financial literacy

Shareholders Proposals for Nominees.  The Nominating Committee will consider written proposals from shareholders for nominees for director. Any such nominations should be submitted to the Nominating Committeec/o the Secretary of the Company and should include the following information: (a) all information relating to such nominee that is required to be disclosed pursuant to Regulation 14A under the Securities Exchange Act of 1934 (including such person’s written consent to being named in the proxy statement as a nominee and to serving as a director if elected); (b) the name(s) and address(es) of the shareholders(s) making the nomination and the number of shares of Common Stock which are owned beneficially and of record by such shareholders(s); and (c) appropriate biographical information and a statement as to the qualification of the nominee, and should be submitted in the time frame described in the Bylaws of the Company and under the caption “Shareholder Proposals for the Annual Meeting for Fiscal Year End 2007”2008” below.

Process for Identifying and Evaluating Nominees.  The process for identifying and evaluating nominees to fill vacancies on the Board of Directors is initiated by conducting an assessment of critical Company and Board needs, based on the present and future strategic objectives of the Company and the specific skills required for the Board as a whole and for each Board Committee. A third-party search firm may be used by the Nominating Committee to identify qualified candidates. These candidates are evaluated by the Nominating Committee by

Beginning on or about May 24, 2006, several derivative actions were filed against certain current and former directors and officers of the Company. These derivative lawsuits were filed in: (1) the Superior Court of King County, Washington, as In re F5 Networks, Inc. State Court Derivative Litigation (CaseNo. 06-2-17195-1 SEA), which consolidates Adams v. Amdahl, et al. (CaseNo. 06-2-17195-1 SEA), Wright v. Amdahl, et al. (CaseNo. 06-2-19159-5 SEA), and Sommer v. McAdam, et al. (CaseNo. 06-2-26248-4 SEA) (the “State Court Derivative Litigation”); and (2) in the U.S. District Court for the Western District of Washington, as In re F5 Networks, Inc. Derivative Litigation, Master FileNo. C06-0794RSL, which consolidates Hutton v. McAdam, et al. (CaseNo. 06-794RSL), Locals 302 and 612 of the International Union of Operating Engineers-Employers Construction Industry Retirement Trust v. McAdam et al. (CaseNo. C06-1057RSL), and Easton v. McAdam et al. (CaseNo. C06-1145RSL). On August 2, 2007, another derivative lawsuit, Barone v. McAdam et al. (CaseNo. C07-1200P), was filed in the U.S. District Court for the Western District of Washington. We expect that this lawsuit will be consolidated with the other lawsuits pending in the U.S. District Court for the Western District of Washington. The complaints generally allege that certain of the Company’s current and former directors and officers, including, in general, each of the Company’s current outside directors (other than Ms. Bevier), Messrs. McAdam, HullDeborah L. Bevier and Eames,Scott Thompson who joined the Company’s Board of Directors in July 2006 and January 2008, respectively) breached their fiduciary duties to the Company by engaging in alleged wrongful conduct concerning the manipulation of certain stock option grant dates. The Company is named solely as a nominal defendant against whom the plaintiffs seek no recovery. Our combined motion to consolidate and stay the State Court Derivative Litigation was granted in a court order dated April 3, 2007. Our motion to dismiss the consolidated federal derivative actions based on plaintiffs’ failure to make demand on the Company’s Board of Directors prior to filing suit was granted in a court order dated August 6, 2007 with leave to amend the allegations in plaintiffs’ complaint. Plaintiffs filed an amended consolidated federal derivative action complaint on September 14, 2007. We intend to vigorously pursue dismissal of the amended complaint and have filed a motion to dismiss based on plaintiffs’ failure to make demand on the Company’s Board of Directors prior to filing suit. Due to the inherent uncertainties of litigation, we are unable to predict the outcome of these matters at this time.

If earned, the cash incentive bonus is paid quarterly. 50% of the cash incentive bonus is based on the Company achieving target revenue for such periodsthe quarter and 50% is based on the Company achieving target adjusted EBITDA (earnings before interest, taxes, depreciation and amortization, excluding certain manufacturing and warranty-related depreciation and amortization expense) for such periods.the quarter. Each such target is determined by the Board of Directors and is set forth in the Board-approved annual budget for each such fiscal year. See footnote (3) of the Grants of Plan-Based Awards Table for Fiscal 2007 for information regarding the targets for fiscal year 2007. No cash incentive bonus will be paid for results less than 80% of an applicable target. The cash incentive bonus is paid linearly above 80% of the targeted goals. Results for both targets must equal or exceed 100% for the total cash incentive bonus to be paid at 100% or more.

The Committee retains some discretion in the administration of the Incentive Plan. In calculating the percentage of target EBITDA achieved for the fourth quarter on fiscal year 2007, the Committee determined it was appropriate to exclude from this calculation a one-time charge of $14 million for in-process research and development related to our acquisition of Acopia in September 2007, as this one-time charge was related to an acquisition and did not arise from or otherwise reflect the Company’s operating results in fiscal year 2007. In fiscal year 2007, the Company achieved 105% of the annual revenue target and 107% of the annual adjusted EBITDA target. As a result, the executive officers may earn additional bonuses for over-achievementearned 106% of these targets. Thetheir target cash incentive bonus for each executive officer constitutes a percentage of each officer’s base salary, ranging from 30% to 60%.in fiscal year 2007. The Committee believes that the cash incentive bonuses paid to the executive officers for performance in 20062007 were merited based on the Company’s outstanding operating results which includedas compared to the targets, increases in market capitalization, total revenue and net income over fiscal year 20052006 of 40 percent43%, 33% and 41 percent17% respectively, and significantcontinued growth in market share.

The Committee believes that equity ownership aligns the interests of executive officers with those of the shareholders and provides significant motivation to executive officers to maximize value for the Company’s shareholders. In accordance with this belief, the Committee periodically approves grants of equity compensation under the Company’s equity incentive plans. The Committee reviews and approves recommendations made by the CEO onamounts of these grants of equity compensation for other executive officers. These recommendations are based on the relative position and responsibilities of each executive officer, previous and expected contributions of each officer to the Company’s success, peer and survey group equity compensation data provided by the outside consultant, previous grants to such officer, and recruitment and retention considerations.

In January 2007, the unique retention value inherent in equity compensation as compared to other formsBoard approved and adopted a “Policy Regarding the Granting of compensation. The RSU grant vests atEquity-Based Compensation Awards,” a copy of which may be found under the rate“About F5 — Investor Relations — Corporate Governance” section of 12.5% upon completion of each quarter of continuous employment at the Company by Mr. McAdam, and will be fully vested on August 1, 2007.

The accounting and tax treatment of the elements of our compensation program is considered in the design of the compensation program. But it is not the sole consideration. Under Section 162(m) of the Internal Revenue Code, the federal income tax deduction for certain types of compensation paid to the chief executive officer and fourthe three other most highly compensated executive officers of publicly held companies (other than the chief executive officer and chief financial officer) is limited to $1 million per officer per fiscal year unless such compensation meets certain requirements. The Committee is aware of this limitation and has decided that it is not appropriate at this time to limit the Company’s discretion to design the compensation packages payable to the Company’s executive officers to comply with these deductibility guidelines.

We have adopted a CodeThe following tables sets forth information concerning compensation for services rendered to us by (a) our Chief Executive Officer (the “CEO”), (b) our Chief Finance Officer (the “CFO”) and (c) our three other most highly compensated executive officers who were serving as our executive officers at the end of Ethics that appliesfiscal year 2007. These executive officers, together with the CEO and CFO, are collectively referred to allas the “Named Executive Officers.”

There are no written employment contracts with any of the Named Executive Officers. Each such officer is an “at-will” employee, and chief accounting officer. The Code of Ethics is posted on the Company’s website. The Internet address for our website iswww.f5.com and the Code of Ethicshis employment may be found under the “investor relations” section ofterminated anytime with or without cause. The RSU and option grant agreements issued to our website. A copyNamed Executive Officers provide that upon certain changes in control of the CodeCompany, the vesting of Ethics may be obtained without charge by written request to the Company’s Secretary. We also haveoutstanding and unvested RSUs and options will accelerate and such RSUs and options will become fully vested. A “change in control” is generally defined as (i) a separate Codesale of Ethics that applies tosubstantially all of the assets of the Company, or (ii) a merger or consolidation in which the Company is not the surviving corporation, or (iii) a reverse merger in which the Company is the surviving corporation but the shares of Common Stock outstanding immediately preceding the merger are converted by virtue of the merger into other property, whether in the form of securities, cash or otherwise, or (iv) the direct or indirect acquisition (including by way of a tender or exchange offer) by any person, or persons acting as a group, of beneficial ownership or a right to acquire beneficial ownership of shares representing a majority of the voting power of the then outstanding shares of capital stock of the Company.

The following table sets forth an estimate of the value of the acceleration of vesting on unvested equity awards which would have occurred if a change in control occurred on September 30, 2007. For purposes of this estimate, the closing price of the Company’s employees, which may be also found undercommon stock on September 28, 2007 of $37.19 per share was used.

The table below summarizes the “investor relations” section of our website.compensation paid by the Company to non-employee directors for the fiscal year ended September 30, 2007.

The Audit Committee consists of threefour directors, each of whom, in the judgment of the Board, is an “independent director” as defined in the listing standards for The Nasdaq Stock Market. The Audit Committee acts pursuant to a written charter that has been adopted by the Board of Directors. The Audit Committee charter is attached to this Proxy Statement as Appendix A and is available on the “investor relations”“About F5 — Investor Relations — Corporate Governance” section of the Company’s website, www.f5.com.www.f5.com.

On behalf of the Board of Directors, the Audit Committee oversees the Company’s financial reporting process and its internal controls over financial reporting, areas for which management has the primary responsibility. PricewaterhouseCoopers, LLP, the independent registered public accounting firm (the “Auditors”), is responsible for expressing an opinion as to the conformity of the audited financial statements with accounting principles generally accepted in the United States of America and for issuing its opinions on management’s assessment and on the effectiveness of the Company’s internal control over financial reporting.

In fulfilling its oversight responsibilities, the Audit Committee has reviewed and discussed with management and the Auditors the audited financial statements and the quarterly unaudited financial statements of the Company for the fiscal year ended September 30, 2006,2007, matters relating to the Company’s internal controls over financial reporting and the processes that support certifications of the financial statements by the Company’s Chief Executive Officer and Chief Accounting Officer.

The Audit Committee discussed with the Auditors the overall scope and plans for the annual audit. The Audit Committee meets with the Auditors, with and without management present, to discuss the results of

The following is a summary of the fees billed to the Company by PricewaterhouseCoopers LLP for professional services rendered for the fiscal years ended September 30, 20062007 and 2005:2006:

Audit Fees.  Consists of fees billed for professional services rendered for the audit of the Company’s consolidated financial statements and review of the interim consolidated financial statements included in quarterly reports and services that are normally provided by PricewaterhouseCoopers LLP in connection with statutory and regulatory filings or engagements including consultations related to compliance with the Sarbanes-Oxley Act of 2002.

Audit-Related Fees.  Consists of fees billed for assurance and related services that are reasonably related to the performance of the audit or review of the Company’s consolidated financial statements and are not reported under “Audit Fees.” These services include accounting consultations in connection with acquisitions, financial accounting and reporting standards and services related to registration statements and public offerings. Substantially all of the Audit-Related Fees in fiscal 20062007 were for services in connection with the restatement resulting from the Company’s review of its stock option practices and historical financial statements.

The following table sets forth information regarding stock price performance contained in this section shall not be deemed to be “soliciting material” or to be “filed” with the Securities and Exchange Commission, nor shall such information be incorporated by reference into any future filings under the Securities Actbeneficial ownership of 1933, as amended, or the Securities Exchange Act of 1934, as amended, except to the extent that the Company specifically incorporates it by reference in such filing.