Proposal 4

On Proposal 4, shares may either be voted FOR the approval of the 2012 Incentive Plan, or voted AGAINST the approval of that plan, or voted to ABSTAIN. If a quorum is represented at the Annual Meeting, the approval of Proposal 4 would require the FOR vote of the holders of a majority of the shares entitled to vote on the proposal and represented in person or by proxy at the Annual Meeting. Because votes to ABSTAIN are counted as shares represented at the meeting, they will have the same effect as votes AGAINST Proposal 4.

Other Matters

An affirmative vote of a majority of the shares represented at the Annual Meeting is generally required for action on any other matters that may properly come before the Annual Meeting.

Effect of Broker Non-Votes

If your shares are held in a brokerage account and you do not instruct your broker how to vote on a particular proposal, your brokerage firm could either:

A broker “non-vote” occurs when a broker or nominee holding shares for a beneficial owner does not vote on a particular proposal because the broker or nominee does not have the discretionary voting power with respect to that proposal and has not received instructions from the beneficial owner. Under applicable rules, brokers do not have discretionary authority to vote on Proposals 1, 3, or 4, but they do have the discretionary authority to vote on Proposal 2.

Shareholders’ Proposals

If you would like to submit a proposal to be included in the Proxy Statement for the 2013 Annual Meeting of Shareholders, the submission must be in writing and received by us no later than December 28, 2012. Submissions of shareholder proposals after that date will be considered untimely for inclusion in the Proxy Statement and form of proxy for our 2013 Annual Meeting. A shareholder proposal that does not qualify under SEC Rule 14a-8 for inclusion in our Proxy Statement must be received by the Corporate Secretary at the principal executive offices of the Company no earlier than February 6, 2013 and no later than March 8, 2013.

All notices of proposals, whether or not to be included in our proxy materials, should be sent to our principal executive offices at Zix Corporation, Attention: Corporate Secretary, 2711 North Haskell Avenue, Suite 2200, LB 36, Dallas, Texas 75204-2960.

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Reducing the Costs of Proxy Solicitation

To reduce the expenses of delivering duplicate proxy materials, we take advantage of the SEC’s “householding” rules that permit us to deliver only one set of proxy materials to shareholders who share an address, unless otherwise requested. If you share an address with another shareholder and have received only one set of proxy materials, you may request a separate copy of these materials at no cost to you by contacting Zix Corporation, Attention: Corporate Secretary, 2711 North Haskell Avenue, Suite 2200, LB 36, Dallas, Texas 75204-2960 or (214) 370-2000. For future Annual Meetings, you may request separate voting materials, or request that we send only one set of proxy materials to you if you are receiving multiple copies, by calling or writing to us at the phone number and address given above.

Shareholders of Record : If you vote on the Internet at www.proxyvote.com, simply follow the prompts for enrolling in the electronic proxy delivery service.

Beneficial Owners : If you hold your shares in a brokerage account, you also may have the opportunity to receive copies of these documents electronically. Please check the information provided in the proxy materials mailed to you by your bank, broker or other holder of record regarding the availability of this service.

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Proposals

P ROPOSAL 1 — E LECTION OF D IRECTORS

Our shareholders will vote on the election of six members of our Board of Directors at the Annual Meeting. Each director will serve until the next Annual Meeting of Shareholders and until the director’s successor is duly elected and qualified, unless earlier removed in accordance with our Bylaws.

The nominees for election to our Board are:

For biographical and other information regarding the nominees for Director, please see “OTHER INFORMATION YOU NEED TO MAKE AN INFORMED DECISION — Directors.” For information on our directors’ compensation, please see “INFORMATION ON THE COMPENSATION OF DIRECTORS.”

Each of the persons nominated for election to our Board of Directors has agreed to stand for election. Our Board of Directors has no reason to believe that any of the nominees will be unable or unwilling to serve if elected, and to the knowledge of the Board, each of the nominees intends to serve the entire term for which election is sought. Our Bylaws provide that the Board of Directors may reduce the number of positions on our Board of Directors. In addition, our Bylaws provide that the Board of Directors may fill any vacancy in the Board of Directors by the affirmative vote of a majority of the remaining Directors.

OUR BOARD OF DIRECTORS RECOMMENDS THAT YOU VOTE

FOR PROPOSAL 1 AND FOR EACH DIRECTOR NOMINEE NAMED ABOVE.

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P ROPOSAL 2 — R ATIFICATION OF A PPOINTMENT OF A CCOUNTANTS

The Audit Committee of the Board has recommended, and the Board has appointed, Whitley Penn LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2012. Services provided to the Company and its subsidiaries by Whitley Penn LLP in fiscal 2011 are described under “INDEPENDENT PUBLIC ACCOUNTANTS.”

We are asking our shareholders to ratify the appointment of Whitley Penn LLP as our independent registered public accounting firm for the 2012 fiscal year. Although ratification is not required by our Bylaws or otherwise, the Board is submitting the appointment of Whitley Penn LLP to our shareholders for ratification as a matter of good corporate practice.

Representatives of Whitley Penn LLP will be present at the Annual Meeting to respond to appropriate questions and to make those statements that they may desire.

Votes cast FOR Proposal 2 by a majority of the shares of our common stock represented at the Annual Meeting is required to approve Proposal 2. Shares voted to ABSTAIN as to Proposal 2 will be counted as represented at the meeting and will have the same effect as a vote against Proposal 2.

If our shareholders do not approve Proposal 2, the appointment of Whitley Penn LLP will be reconsidered by our Audit Committee and our Board. Even if Proposal 2 is approved, the Audit Committee in its discretion may select a different independent registered public accounting firm if it determines that a change would be in the best interests of the Company and our shareholders and otherwise complies with all regulations of the SEC regarding a change in public accounting firms.

OUR BOARD OF DIRECTORS RECOMMENDS

THAT YOU VOTE FOR PROPOSAL 2.

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P ROPOSAL 3 — A PPROVE , ON AN A DVISORY BASIS , THE C OMPENSATION OF OUR N AMED E XECUTIVE O FFICERS

The Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010 (“Dodd-Frank Act”), enables the Company’s shareholders to vote to approve, on an advisory (nonbinding) basis, the compensation of the Company’s named executive officers. The Company seeks your advisory vote and asks that you support the compensation of the named executive officers as disclosed in this proxy statement. Our Board of Directors intends to conduct an annual advisory vote on the compensation of the Company’s named executive officers.

As described in detail under “COMPENSATION DISCUSSION AND ANALYSIS,” our compensation programs are designed to motivate our executives to create a successful company. We believe that our compensation program, with its balance of short-term incentives and long-term incentives (including equity awards that vest over multiple years) reward sustained performance that is aligned with long-term shareholder interests.

This proposal, commonly known as a “say on pay” proposal, gives the Company’s shareholders the opportunity to express their views on the compensation of its named executive officers. This vote is not intended to address any specific item of compensation, but rather the overall compensation of the Company’s named executive officers described in this proxy statement.

Accordingly, the Board invites you to review carefully the Compensation Discussion and Analysis beginning on page 32 and the tabular and other disclosures on compensation under Executive Compensation beginning on page 37, and cast a vote to approve the Company’s executive compensation programs through the following resolution:

“Resolved, that shareholders approve the compensation of the Company’s named executive officers, as discussed and disclosed in the Compensation Discussion and Analysis, the executive compensation tables, and any narrative executive compensation disclosure contained in this proxy statement.”

The say-on-pay vote is advisory, and therefore not binding on the Company, the Compensation Committee or the Board of Directors. The Board of Directors and Compensation Committee value the opinions of the Company’s shareholders and to the extent there is any significant vote against the named executive officers compensation as disclosed in this proxy statement, the Board will consider the shareholders’ concerns and the Compensation Committee will evaluate whether any actions are necessary to address those concerns, particularly in the event that there is a significant vote against the compensation of our named executive officers as disclosed in this proxy statement. Our Board intends to hold an annual advisory vote for shareholders to approve the compensation of our named executive officers.

OUR BOARD OF DIRECTORS RECOMMENDS

THAT YOU VOTE FOR PROPOSAL 3.

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P ROPOSAL 4 — A PPROVAL OF 2012 I NCENTIVE P LAN

On April 13, 2012, the Board of Directors adopted the 2012 Incentive Plan, subject to shareholder approval at the Annual Meeting. If approved by shareholders, the effective date of the 2012 Incentive Plan will be the date it was approved by the Board.

The 2012 Incentive Plan is intended to serve as the successor to the Company’s 2006 Directors’ Stock Option Plan, 2004 Stock Option Plan, and 2003 New Employee Stock Option Plan (the “Existing Plans”). As of March 31, 2012, there were approximately 7,293,835 shares of Common Stock subject to outstanding awards issued under the Existing Plans. Approximately 1,327,000 of these outstanding awards are options that have an exercise price that greatly exceeds the current trading price of the Company’s common stock and are scheduled to expire in 2013 and 2014 (the “Expiring Options”). Approximately 536,313 shares of Common Stock remain reserved and available for future awards under the Existing Plans.

In April 2012, the Compensation Committee directed management to engage Board Advisory LLC, an independent compensation consultant, to assist the Company in determining the number of shares subject to the 2012 Incentive Plan. Among other things, Board Advisory reviewed the number of shares subject to the Company’s outstanding awards under the Existing Plans (commonly referred to as “option overhang”), its prior rate of grant under the Existing Plans (commonly referred to as “annual burn rate”), and its prior grants to executive officers, and evaluated these amounts in light of the competitive practices of a group of companies in the Company’s industry. This peer group was limited to companies having the same global industry classification standards code (GICS) as the Company and having between 0.5 and 2 times the Company’s revenue and market cap. This peer group analysis indicated that the Company requires additional shares to enable it to make competitive awards and to more closely align executive pay with shareholder interests. The analysis showed that the number of shares awarded by the Company over the past three years is considerably lower than peer companies. Based on competitive practice, the Company expects to grant between 1 and 2% of outstanding shares on an annual basis. Accordingly, the requested shares are expected to last for approximately four years.

If approved by shareholders, 2,700,000 shares would be available for issuance under the 2012 Incentive Plan, plus a number of additional shares (not to exceed 1,327,000) underlying options outstanding under the Existing Plans that terminate or expire unexercised, or are cancelled, forfeited or lapse for any reason. This number of authorized shares is subject to proportionate adjustment in the event of stock splits and similar events.

If the shareholders approve the 2012 Incentive Plan, all future equity grants to the Company’s employees, officers, directors and consultants will be made from the 2012 Incentive Plan, and the Company will not grant any additional awards to such persons under the Existing Plans. If the shareholders do not approve the 2012 Incentive Plan, the Company will continue granting awards under the Existing Plans.

A summary of the 2012 Incentive Plan is set forth below. This summary is qualified in its entirety by the full text of the 2012 Incentive Plan, which is attached to this Proxy Statement as Appendix A .

Summary of the 2012 Incentive Plan

Promotion of Sound Corporate Governance Practices . The 2012 Incentive Plan contains a number of provisions that the Company believes are consistent with the interests of the shareholders and sound corporate governance practices, including:

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Key Data Relating to Outstanding Equity Awards and Shares Available

The following table includes information regarding outstanding equity awards and shares available for future awards under the Existing Plans as of March 31, 2012 (and without giving effect to approval of the 2012 Incentive Plan under this Proposal):

Purpose.   The purpose of the 2012 Incentive Plan is to promote the Company’s success by linking the personal interests of the Company’s employees, officers, directors and consultants to those of the shareholders, and by providing participants with an incentive for outstanding performance. The 2012 Incentive Plan is also intended

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to enhance the Company’s ability to motivate, attract, and retain the services of employees, officers, directors and consultants upon whose judgment, interest, and special effort the successful conduct of the Company’s operation is largely dependent.

Administration.   The 2012 Incentive Plan will be administered by the Compensation Committee of the Board of Directors. The Compensation Committee will have the authority to grant awards; designate participants; determine the type or types of awards to be granted to each participant and the number, terms and conditions thereof; establish, adopt or revise any plan, program or policy for the grant of awards as it may deem necessary or advisable, including but not limited to short-term incentive programs; establish, adopt or revise any rules and regulations as it may deem advisable to administer the 2012 Incentive Plan; and make all other decisions and determinations that may be required under the 2012 Incentive Plan. The independent Director members of our Board of Directors may at any time administer the 2012 Incentive Plan.

Eligibility . The 2012 Incentive Plan permits the grant of incentive awards to employees, officers, directors and consultants of the Company and its affiliates as selected by the Compensation Committee. As of March 31, 2012, the number of eligible participants was approximately 132. The number of eligible participants may increase over time based upon future growth of the Company and its affiliates.

Grants to Non-Employee Directors. Grants of awards to non-employee directors under the 2012 Incentive Plan will be made only in accordance with the terms, conditions and parameters of a plan, program or policy for the compensation of non-employee directors as in effect from time to time. Accordingly, the Compensation Committee and Board may not make discretionary grants to non-employee directors under the 2012 Incentive Plan.

Permissible Awards.   The 2012 Incentive Plan authorizes the granting of awards in any of the following forms:

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Shares Available for Awards.  The aggregate number of shares of Common Stock that may be issued under the 2012 Incentive Plan is 2,700,000 shares, plus a number of additional shares (not to exceed 1,327,000) underlying options outstanding under the Existing Plans that thereafter terminate or expire unexercised, or are cancelled, forfeited or lapse for any reason. This number of authorized shares is subject to proportionate adjustment in the event of stock splits and similar events.

Share Counting. As noted above, the 2012 Incentive Plan utilizes a fungible share pool under which each stock option and SAR counts against the share reserve on a one-for-one basis, and each full-value award counts against the share reserve on a greater than one-for-one basis. Specifically, shares of common stock reserved and available for issuance pursuant to awards granted under the 2012 Plan shall be counted against the plan reserve as follows:

Limitations on Individual Awards.   The maximum aggregate number of shares of common stock subject to stock-based awards that may be granted under the 2012 Incentive Plan in any 12-month period to any one participant is as follows:

The maximum aggregate amount awarded or credited with respect to cash-based awards under the 2012 Incentive Plan to any one participant in any 12-month period is $5,000,000.

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Minimum Vesting Requirements. Except in the case of substitute awards (which are awards honored or assumed, or new rights substituted therefor, by the new employer following a change in control of the Company) and replacement awards (which are awards made to employees of companies acquired by the Company to replace incentive awards held by such employees prior to the acquisition), full-value awards granted under the 2012 Incentive Plan will either (i) be subject to a minimum vesting period of three years (which may include graduated vesting within such three-year period), or one year if the vesting is based on performance criteria other than continued service, or (ii) be granted solely in exchange for foregone cash compensation. Notwithstanding the foregoing, (i) the Committee may permit acceleration of vesting of such full-value awards in the event of the participant’s death, disability or retirement, or the occurrence of a change in control, and (ii) the Committee may grant full-value awards covering 10% or fewer of the total number of shares authorized under the 2012 Incentive Plan without respect to these minimum vesting requirements.

Performance Goals.  All options and SARs granted under the 2012 Incentive Plan are designed to be exempt from the $1,000,000 deduction limit imposed by Code Section 162(m). The Compensation Committee may designate any other award granted under the 2012 Incentive Plan as a qualified performance-based award in order to make the award fully deductible without regard to the $1,000,000 deduction limit imposed by Code Section 162(m). If an award is so designated, the Compensation Committee must establish objectively determinable performance goals for the award based on one or more of the following business criteria, which may be expressed in terms of Company-wide objectives or in terms of objectives that relate to the performance of an affiliate or a division, region, department or function within the Company or an affiliate: revenue (premium revenues, total revenue or other revenue measures), sales, new first year orders, profit (net profit, gross profit, operating profit, economic profit, profit margins or other corporate profit measures), earnings (EBIT, EBITDA, earnings per share, earnings after capital charge, or other corporate earnings measures), net income (before or after taxes, operating income or other income measures), cash (cash flow, cash generation or other cash measures), stock price or performance, total shareholder return (stock price appreciation plus reinvested dividends divided by beginning share price), economic value added return measures (including, but not limited to, return on assets, capital, equity, investments or sales, and cash flow return on assets, capital, equity, or sales), market share, improvements in capital structure, expenses (expense management, expense ratio, expense efficiency ratios or other expense measures), business expansion or consolidation (acquisitions and divestitures), internal rate of return or increase in net present value, productivity measures, cost reduction measures, strategic plan development and implementation, and working capital (including, but not limited to, targets relating to inventory and/or accounts receivable).

The Compensation Committee must establish such goals within the time period prescribed under applicable tax regulations, and the Compensation Committee may for any reason reduce (but not increase) any award, notwithstanding the achievement of a specified goal. The Compensation Committee may provide, at the time the performance goals are established, that any evaluation of performance will exclude or otherwise objectively adjust for any specified circumstance or event that occurs during a performance period, including by way of example but without limitation the following: asset write-downs or impairment charges, litigation or claim judgments or settlements, the effect of changes in tax laws, accounting principles or other laws or provisions affecting reported results, accruals for reorganization and restructuring programs, extraordinary nonrecurring items as described in then-current accounting principles, extraordinary nonrecurring items as described in management’s discussion and analysis of financial condition and results of operations appearing in the Company’s annual report to shareholders for the applicable year, acquisitions or divestitures and foreign exchange gains and losses.

Treatment of Awards upon a Change of Control . Unless otherwise provided in an award agreement or any special plan document governing an award:

(A) with respect to awards assumed by the surviving entity or otherwise equitably converted or substituted in connection with a change in control, if within one year after the effective date of the change in control, a participant’s employment is terminated without Cause (as defined in the 2012 Incentive Plan) or the participant resigns for Good Reason (if the participant is party to an agreement, such as an employment agreement or award agreement, which contains a definition of “Good Reason”), then

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(B) upon the occurrence of a change in control in which awards are not assumed by the surviving entity or otherwise equitably converted or substituted in connection with the change in control in a manner approved by the Compensation Committee or the board of directors:

Discretionary Acceleration. Regardless of whether a change in control has occurred, the Compensation Committee may in its sole discretion at any time determine that all or a portion of a participant’s awards will become fully vested, subject to the minimum vesting requirements applicable to full-value awards discussed above. The Compensation Committee may discriminate among participants or among awards in exercising such discretion.

Limitations on Transfer; Beneficiaries.   A participant generally may not assign or transfer an award other than by will or the laws of descent and distribution or, except in the case of an incentive stock option, pursuant to a domestic relations order that would satisfy the Code. The Compensation Committee may, however, permit other transfers (other than transfers for value) where it concludes that such transferability does not result in accelerated taxation, does not cause any option intended to be an incentive stock option to fail to qualify as such, and is otherwise appropriate and desirable, taking into account any factors deemed relevant, including without limitation, any state or federal tax or securities laws or regulations applicable to transferable awards. A participant may, in the manner determined by the Committee, designate a beneficiary to exercise the rights of the participant and to receive any distribution with respect to any award upon the participant’s death.

Adjustments. In the event of a transaction between the Company and its shareholders that causes the per-share value of the common stock to change (including, without limitation, any stock dividend, stock split, spin-off, rights offering, or large nonrecurring cash dividend), the share authorization limits under the 2012 Incentive Plan will be adjusted proportionately, and the Compensation Committee must make such adjustments to the 2012 Incentive Plan and awards as it deems necessary, in its sole discretion, to prevent dilution or enlargement of rights immediately resulting from such transaction. In the event of a stock split, a stock dividend, or a combination or consolidation of the outstanding common stock into a lesser number of shares, the authorization limits under the 2012 Incentive Plan will automatically be adjusted proportionately, and the shares then subject to each award will automatically be adjusted proportionately without any change in the aggregate purchase price.

Termination and Amendment.  The Board or the Compensation Committee may, at any time and from time to time, terminate or amend the 2012 Incentive Plan, but if an amendment would constitute a material amendment requiring shareholder approval under applicable listing requirements, laws, policies or regulations, then such amendment will be subject to shareholder approval. In addition, the Board or the Compensation Committee may condition any amendment on the approval of the shareholders for any other reason. No termination or amendment of the 2012 Incentive Plan may, without the written consent of the participant, reduce or diminish the value of an outstanding award.

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The Compensation Committee may amend or terminate outstanding awards. However, such amendments may require the consent of the participant and, unless approved by the shareholders, the exercise price of an outstanding option may not be reduced, directly or indirectly, and the original term of an option may not be extended.

Prohibition on Repricing.  As indicated above under “Termination and Amendment,” outstanding stock options and SARs cannot be repriced, directly or indirectly, without shareholder approval. The exchange of an “underwater” option or SAR (i.e., an option or SAR having an exercise or base price in excess of the current market value of the underlying stock) for another award would be considered an indirect repricing and would, therefore, require shareholder approval.

Certain Federal Income Tax Effects

The U.S. federal income tax discussion set forth below is intended for general information only and does not purport to be a complete analysis of all of the potential tax effects of the 2012 Incentive Plan. It is based upon laws, regulations, rulings and decisions now in effect, all of which are subject to change. State and local income tax consequences are not discussed, and may vary from locality to locality.

Nonstatutory Stock Options.   There will be no federal income tax consequences to the optionee or to us upon the grant of a nonstatutory stock option under the 2012 Incentive Plan. When the optionee exercises a nonstatutory option, however, he or she will recognize ordinary income in an amount equal to the excess of the fair market value of the common stock received upon exercise of the option at the time of exercise over the exercise price, and we will be allowed a corresponding federal income tax deduction. Any gain that the optionee realizes when he or she later sells or disposes of the option shares will be short-term or long-term capital gain, depending on how long the shares were held.

Incentive Stock Options.   There typically will be no federal income tax consequences to the optionee or to us upon the grant or exercise of an incentive stock option. If the optionee holds the acquired option shares for the required holding period of at least two years after the date the option was granted and one year after exercise, the difference between the exercise price and the amount realized upon sale or disposition of the option shares will be long-term capital gain or loss, and we will not be entitled to a federal income tax deduction. If the optionee disposes of the option shares in a sale, exchange, or other disqualifying disposition before the required holding period ends, he or she will recognize taxable ordinary income in an amount equal to the excess of the fair market value of the option shares at the time of exercise over the exercise price, and we will be allowed a federal income tax deduction equal to such amount. While the exercise of an incentive stock option does not result in current taxable income, the excess of the fair market value of the option shares at the time of exercise over the exercise price will be an item of adjustment for purposes of determining the optionee’s alternative minimum taxable income.

SARs.  A participant receiving a stock appreciation right under the 2012 Incentive Plan will not recognize income, and we will not be allowed a tax deduction, at the time the award is granted. When the participant exercises the stock appreciation right, the amount of cash and the fair market value of any shares of common stock received will be ordinary income to the participant and we will be allowed a corresponding federal income tax deduction at that time.

Restricted Stock. Unless a participant makes an election to accelerate recognition of the income to the date of grant as described below, a participant will not recognize income, and we will not be allowed a tax deduction, at the time a restricted stock award is granted, provided that the award is nontransferable and is subject to a substantial risk of forfeiture. When the restrictions lapse, the participant will recognize ordinary income equal to the fair market value of the common stock as of that date (less any amount he or she paid for the stock), and we will be allowed a corresponding federal income tax deduction at that time, subject to any applicable limitations under Code Section 162(m). If the participant files an election under Code Section 83(b) within 30 days after the date of grant of the restricted stock, he or she will recognize ordinary income as of the date of grant equal to the fair market value of the stock as of that date (less any amount paid for the stock), and we will be allowed a corresponding

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federal income tax deduction at that time, subject to any applicable limitations under Code Section 162(m). Any future appreciation in the stock will be taxable to the participant at capital gains rates. However, if the stock is later forfeited, the participant will not be able to recover the tax previously paid pursuant to the Code Section 83(b) election.

Restricted or Deferred Stock Units.  A participant will not recognize income, and we will not be allowed a tax deduction, at the time a stock unit award is granted. When the participant receives or has the right to receive shares of common stock (or the equivalent value in cash or other property) in settlement of a stock unit award, a participant will recognize ordinary income equal to the fair market value of the common stock or other property as of that date (less any amount he or she paid for the stock or property), and we will be allowed a corresponding federal income tax deduction at that time, subject to any applicable limitations under Code Section 162(m).

Performance Awards.  A participant will not recognize income, and the Company will not be allowed a tax deduction, at the time a performance award is granted (for example, when the performance goals are established). Upon receipt of cash, stock or other property in settlement of a performance award, the participant will recognize ordinary income equal to the cash, stock or other property received, and the Company will be allowed a corresponding federal income tax deduction at that time, subject to any applicable limitations under Code Section 162(m).

Dividend Equivalents. A participant will recognize ordinary income, and we will be allowed a tax deduction, at the time the dividend equivalents are paid or payable.

Code Section 409A . The 2012 Incentive Plan permits the grant of various types of incentive awards, which may or may not be exempt from Code Section 409A. If an award is subject to Section 409A, and if the requirements of Section 409A are not met, the taxable events as described above could apply earlier than described, and could result in the imposition of additional taxes and penalties. Restricted stock awards, and stock options and stock appreciation rights that comply with the terms of the 2012 Incentive Plan are generally exempt from the application of Code Section 409A. Stock units, other stock-based awards and cash-based awards that are granted in one year and payable in a later year generally are subject to Section 409A unless they are designed to satisfy the short-term deferral exemption from such law. If not exempt, such awards must be specially designed to meet the requirements of Section 409A in order to avoid early taxation and penalties.

Tax Withholding . The Corporation or any affiliate has the right to deduct or withhold, or require a participant to remit to the Corporation, an amount sufficient to satisfy federal, state, and local taxes (including employment taxes) required by law to be withheld with respect to any exercise, lapse of restriction or other taxable event arising as a result of the 2012 Incentive Plan.

Benefits to Named Executive Officers and Others

As of the date of this proxy statement, no awards had been granted under the 2012 Incentive Plan. All awards under the 2012 Incentive Plan will be made at the discretion of the Compensation Committee. Therefore, it is not currently possible to determine the benefits or amounts that will be received by any individuals or groups pursuant to the 2012 Incentive Plan in the future.

Vote Required and Board of Directors Recommendation

Votes cast FOR Proposal 4 by a majority of the shares of our common stock represented at the Annual Meeting and entitled to vote on the proposal is required to approve the 2012 Incentive Plan. Shares voted to ABSTAIN as to Proposal 4 will be counted as represented at the meeting and will have the same effect as a vote AGAINST Proposal 4. If you hold your shares in street name and you do not provide voting instructions to your bank or broker, it will have no impact on the outcome of Proposal 4, as broker non-votes are not entitled to vote on the matter.

OUR BOARD OF DIRECTORS RECOMMENDS THAT YOU

VOTE FOR PROPOSAL 4.

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Taher A. Elgamal was elected to ZixCorp’s Board of Directors in July 2011. Dr. Elgamal is co-founder, CEO and director of IdentityMind, Inc. (online anti-fraud). He currently serves as a director of privately-held Vindicia, Inc. (online billing). Dr. Elgamal has also held executive roles at technology and security companies, including CSO of Axway, Inc. (business interaction networks) from 2008 to 2011, CTO of Tumbleweed Communications (secure email and file transfer) from 2006 to 2008, CTO of Securify, Inc. (network security) from 2001 to 2004, CEO and president of Securify, Inc. from 1998 to 2001 and chief scientist of Netscape Communications (internet) from 1995 to 1998. Dr. Elgamal is a recipient of the RSA Conference 2009 Lifetime Achievement Award, and he is recognized as the “father of SSL,” the Internet security standard Secure Sockets Layer. Dr. Elgamal was issued several patents in online security, payments and data compression. He received a bachelor’s degree in electrical engineering from Cairo University, a master’s degree in electrical engineering from Stanford University and a doctorate in electrical engineering from Stanford University.

Our Board of Directors selected Dr. Elgamal to serve as a director because of his expertise in cybersecurity and encryption technologies. In addition, his experience working with data security firms contributes to the Board’s oversight of the Company’s cybersecurity risks as well as its marketing strategy. His experience as an executive and director at public and private information technology companies adds to the Board understanding of many matters facing the Company, including personnel management, business operations and corporate governance.

Robert C. Hausmann was elected to our Board of Directors in November 2005. He is the Chief Financial Officer of privately-held TetraSun, Inc. (solar cell development). Mr. Hausmann served as Vice President and Chief Financial Officer of Securify, Inc. (computer security monitoring) from September 2002 through June 2005. From September 1999 through September 2002, Mr. Hausmann served as Vice President and Chief Financial Officer of Resonate, Inc. (network traffic management) and helped manage that company’s initial public offering. Previously, he served as Operations Partner and Chief Financial Officer of Mohr, Davidow Ventures, a Silicon Valley-based venture capital partnership. He is a Director of Business Services Group LLC, CAY Holding, Sam Cloud Barn L.P., and EasyIce, LLC. Mr. Hausmann holds a Master of Business Administration degree from Santa Clara University and a Bachelors of Arts degree in Finance and Accounting from Bethel University.

Our Board of Directors selected Mr. Hausmann to serve as a director because of his experience as Chief Financial Officer of four; and as Chief Financial Officer of one of Silicon Valley’s premiere venture capital firms, which contributes to the Board’s oversight of the Company’s financial and accounting matters, including public company reporting and disclosure. His consulting work at public and private companies, principally in the information technology industry, brings to the Board valuable experience and perspective on a variety of matters facing the Company, including financial markets, operations, corporate governance, compliance and systems and process re-engineering.

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James S. Marston was elected to our Board in September 1991. From September 1987 through February 1998, Mr. Marston served as a Senior, or Executive, Vice President and the Chief Information Officer of APL Limited (intermodal shipping). Between 1986 and 1987, Mr. Marston served as President of AMR Technical Training Division, AMR Corporation (transportation). From 1982 until 1986, he was Vice President of Data Processing and Communications for American Airlines, Inc., where he was responsible for the Sabre reservations system and related technologies. He holds a Bachelor of Arts degree in Political Science from the University of Maryland, and a Master of Arts degree in Public Administration from the University of Oklahoma.

Our Board of Directors selected Mr. Marston to serve as a director because his 20 years of service on our Board contributes unique knowledge, history and perspective about the Company and its business, employees and customers. His tenure provides the Board with a deeper understanding of the issues, risks and opportunities before the Company. Mr. Marston’s years operating the Sabre computer reservation system, then owned by American Airlines, Inc., contributes to the Board a wealth of experience and depth of understanding about issues facing large and complex information technology services businesses.

Maribess L. Miller was elected to our Board in April 2010. Ms. Miller was a member of the public accounting firm PricewaterhouseCoopers LLP from 1975 until 2009, including serving as the North Texas Market Managing Partner from 2001 until 2009; as Southwest Region Consumer, Industrial Products and Services Leader from 1998 until 2001; and as Managing Partner of that firm’s U.S. Healthcare Audit Practice from 1995 to 1998. She was appointed in 2009 by Governor Rick Perry to the Texas State Board of Public Accountancy and serves on the rules committee and chairs the behavioral enforcement committee. Ms. Miller also serves on the TCU Neeley School of Business Board of Visitors, and was audit committee chair of the Dallas Symphony Association in 2009-10. She graduated cum laude with a Bachelors degree in Accounting from Texas Christian University. Ms. Miller is a Certified Public Accountant.

Our Board of Directors selected Ms. Miller to serve as a director because of her extensive experience in auditing and consulting with companies in various fields, including healthcare and technology companies, which allows her to contribute valuable perspective and insights about the Company’s operations. In addition, Ms. Miller has special expertise in public company accounting and financial reporting. She brings to our Board and its Audit Committee invaluable technical understanding of public company accounting and internal controls over financial reporting.

Antonio R. Sanchez III was elected to our Board in May 2003. He has served since 2011 as chairman of the board, president and chief executive officer of Sanchez Energy Corporation, an oil and gas production company traded on the New York Stock Exchange. Since 2001, he has served as president of Sanchez Oil & Gas Corporation (oil and gas production) and as president of SEP Management I, LLC (oil and gas production). From 1999 through 2001, he worked in a variety of positions at Zix Corporation, including sales and marketing, product development and investor relations. From 1997 through 1999, he was an investment banker specializing in mergers and acquisitions with JP Morgan Securities Inc. (financial services). He received a Bachelor of Science degree in Business Administration from Georgetown University with a concentration on Accounting and Finance and a minor in Economics. He also holds a Master of Business Administration degree from Harvard University.

Our Board of Directors selected Mr. Sanchez to serve as a director because his experience in senior executive roles at a company with revenues significantly larger than those of the Company, and in an industry that is distinct from the Company’s industry, brings to our Board a unique “outsider’s” perspective. Mr. Sanchez’s early career experience as an employee of the Company provides him with valuable historical knowledge and perspective about our business.

Richard D. Spurr was elected to our Board in May 2005 and elected Chairman of the Board in February 2006. He joined our Company in January 2004 as President and Chief Operating Officer and has served as Chief Executive Officer since March 2005. From March 2003 to November 2003, he served as Senior Vice President, Worldwide Sales, Marketing and Business Development for Securify, Inc. (information security). From 1997 to 2001 he served in several senior executive positions at Entrust, Inc. (information technology security) including VP of Sales, Marketing, Business Development and Professional Services, helping to take this technology company from an early stage to and beyond the initial public offering. From 1991 to 1996, he served in several senior executive positions at SEER Technologies, Inc. (information technology) and from 1974 to 1990, he worked for IBM Corporation (information technology) where, as Regional Manager, he was responsible for over 1,000

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employees, and as Group Director in Tokyo, where he managed a $1.2 billion Asia Pacific business. Mr. Spurr earned a Bachelor of Arts degree from the University of Notre Dame.

Our Board of Directors selected Mr. Spurr to serve as a director because as the Company’s Chief Executive Officer his direct, day-to-day knowledge of and interaction with all aspects of our business, including shareholders, employees and customers is unique among the directors and provides our Board with important insights into our Company’s business. In addition, he brings over 30 years of experience in building and managing sales, marketing, business development and service operations in global information technology businesses, which is unique among the members of our Board.

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Richard D. Spurr was elected to our Board in May 2005 and elected Chairman of the Board in February 2006. He joined our Company in January 2004 as President and Chief Operating Officer and has served as Chief Executive Officer since March 2005. From March 2003 to November 2003, he served as Senior Vice President, Worldwide Sales, Marketing and Business Development for Securify, Inc. (information security). From 1997 to 2001 he served in several senior executive positions at Entrust, Inc. (information technology security) including VP of Sales, Marketing, Business Development and Professional Services, helping to take this technology company from an early stage to and beyond the initial public offering. From 1991 to 1996, he served in several senior executive positions at SEER Technologies, Inc. (information technology) and from 1974 to 1990, he worked for IBM Corporation (information technology) where, as Regional Manager, he was responsible for over 1,000 employees, and as Group Director in Tokyo, where he managed a $1.2 billion Asia Pacific business. Mr. Spurr earned a Bachelor of Arts degree from the University of Notre Dame.

James F. Brashear has served as Vice President, General Counsel and Corporate Secretary since February 2010. From September 2007 until joining our Company, Mr. Brashear was a partner at the law firm Haynes and Boone, LLP. From July 1996 until August 2007, he served in various executive capacities at Sabre Holdings Corporation (travel commerce) including Senior Vice President, Deputy General Counsel, Corporate Secretary and Chief Governance Officer. He was previously an attorney at AMR Corporation’s subsidiary American Airlines, Inc. (air transportation), and at the law firms Skadden, Arps, Slate, Meagher & Flom and O’Melveny & Myers. Mr. Brashear received a Juris Doctorate degree, magna cum laude, from the University of San Diego School of Law and a Bachelor of Arts degree from the University of California at San Diego. He is a member of the Bar of the United States Supreme Court, the California Bar Association and the State Bar of Texas. He served from 2004 to 2011 as a national director of The Society of Corporate Secretaries and Governance Professionals.

Michael W. English has served as our Chief Financial Officer (CFO) since July 2011. Since joining the Company in June 2007, he has served in many roles, including Controller and Treasurer. Mr. English is a certified public accountant and has more than 30 years of experience in finance and accounting. Before joining the Company, Mr. English was Vice President of Finance for Advance Fibre Communications (telecommunications) from March 2004 through June 2005, and Vice President of Finance for Marconi, PLC (telecommunications) from June 1999 to February 2004. Previously, he served as Division Controller for the Access Division of RELTEC Corporation, Division Controller at Rockwell Automation and Division Controller at Reliance Electric Company. Mr. English earned a Masters degree in accountancy from DePaul University and a Bachelor of Arts degree in English from John Carroll University. In July 2009, Mr. English was discharged from personal debts pursuant to a voluntary petition filed in April 2009 under federal bankruptcy laws.

Russell J. Morgan has served as our Vice President, Client Services since September 2002. From February 1997 until August 2002, he worked at Entrust, Inc. (information technology security) where he held a variety of senior management positions, including director, professional services and senior director, Entrust.net. At Entrust, he founded the professional services organization and then managed the business and technical operations for the Entrust.net business unit. Previously, he held several management positions at Lockheed Martin (aerospace), where he specialized in secure messaging and military command and control systems. Mr. Morgan is a professional engineer with over 30 years experience in managing, delivering and supporting complex customer-focused

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technology solutions. Mr. Morgan holds a Bachelor of Engineering degree from Concordia University, Montreal, Quebec, Canada.

David J. Robertson has served as our Vice President, Engineering since March 2002. Mr. Robertson has over 30 years of experience in the internet and telecommunications industries, with specific expertise in hosted network architecture, electronic security, communication protocols, software systems and wireless infrastructure. From 1981 through 2000, he was employed by Nortel Networks (telecommunications), where he held technology Vice President positions in the Wireless, Carrier and Enterprise Divisions. From 2001 to 2002, he participated in creating technology startup companies with STARTech Early Ventures (venture capital). He has been a participant in several industry standards-setting groups and serves with the City of Richardson Chamber of Commerce. He holds a Bachelor of Science degree in Electrical Engineering from the University of Waterloo, Canada, and a Master’s degree in Engineering from Carleton University, Canada.

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