Exhibit 3.1

CERTIFICATE OF DESIGNATIONS OF

SERIES A CONVERTIBLE PREFERRED STOCK,

PAR VALUE $1.00,

OF

ZIX CORPORATION

ZIX CORPORATION, a corporation organized and existing under the Business Organizations Code of the State of Texas (the “Company”), in accordance with the provisions of Sections 21.155 and 21.156 thereof:

HEREBY CERTIFIES:

That, the Restated Articles of Incorporation (the “Articles of Incorporation”) of the Company, as filed with the Secretary of State of the State of Texas, authorizes the issuance of 185,000,000 shares of capital stock, consisting of 175,000,000 shares of common stock, $0.01 par value (“Common Stock”), and 10,000,000 shares of preferred stock, $1.00 par value (“Preferred Stock”);

That, the Articles of Incorporation expressly authorize the Board of Directors of the Company (the “Board”) by resolution or resolutions, subject to limitations prescribed by law and by Article IV of the Articles of Incorporation, to provide for the issuance of Preferred Stock as a class or in one or more series and, with respect to each series of Preferred Stock, to establish the number of shares included in each such series and to fix the designations, powers, relative rights, qualifications, preferences, limitations and restrictions of the shares of such series not fixed by the Articles of Incorporation;

That, pursuant to the authority conferred upon the Board by the Articles of Incorporation, the Board, on January 11, 2019, adopted the following resolution designating a new series of Preferred Stock as “Series A Convertible Preferred Stock”:

RESOLVED, that, pursuant to the authority vested in the Board in accordance with the provisions of Article IV of the Articles of Incorporation and the provisions of Section 21.155 of the Texas Business Organizations Code, a series of Preferred Stock of the Company is hereby authorized, and the number of shares to be included in such series, and the designations, powers, relative rights, qualifications, preferences, limitations and restrictions of the shares of Preferred Stock included in such series, shall be as follows:

SECTION 1. Designation and Number of Shares. The shares of such series of Preferred Stock shall be designated as “Series A Convertible Preferred Stock” (the “Series A Preferred Stock”). The number of authorized shares constituting the Series A Preferred Stock shall be 64,914 (or up to 100,914 shares if the shares of the Series B Preferred Stock issued on the Original Issuance Date are automatically converted into shares of Series A Preferred Stock in accordance with the terms of Section 6 of the Series B Certificate). That number from time to time may be increased or decreased (but not below the number of shares of Series A Preferred

Stock then outstanding) by further resolution duly adopted by the Board, or any duly authorized committee thereof and by the filing of a certificate pursuant to the provisions of the Texas Business Organizations Code stating that such increase or decrease, as applicable, has been so authorized. The Company shall not have the authority to issue fractional shares of Series A Preferred Stock.

SECTION 2. Ranking. The Series A Preferred Stock will rank, with respect to dividend rights and rights on the distribution of assets on any voluntary or involuntary liquidation, dissolution or winding up of the affairs of the Company:

(a) on a parity basis with each other class or series of Capital Stock of the Company now existing or hereafter authorized, the terms of which expressly provide that such class or series ranks on a parity basis with the Series A Preferred Stock as to dividend rights and rights on the distribution of assets on any voluntary or involuntary liquidation, dissolution or winding up of the affairs of the Company (such Capital Stock, “Parity Stock”); and the Series B Preferred Stock shall be deemed to be Parity Stock and the Series A Preferred Stock shall rank on a parity basis with the Series B Preferred Stock as to dividend rights and rights on the distribution of assets on any voluntary or involuntary liquidation, dissolution or winding up of the affairs of the Company;

(b) junior to each other class or series of Capital Stock of the Company now existing or hereafter authorized, the terms of which expressly provide that such class or series ranks senior to the Series A Preferred Stock as to dividend rights and rights on the distribution of assets on any voluntary or involuntary liquidation, dissolution or winding up of the affairs of the Company (such Capital Stock, “Senior Stock”); and

(c) senior to the Common Stock and each other class or series of Capital Stock of the Company now existing or hereafter authorized, the terms of which do not expressly provide that such class or series ranks on a parity basis with or senior to the Series A Preferred Stock as to dividend rights and rights on the distribution of assets on any voluntary or involuntary liquidation, dissolution or winding up of the affairs of the Company (such Capital Stock, “Junior Stock”).

SECTION 3. Definitions. As used herein with respect to Series A Preferred Stock:

“Accreted Value” has the meaning set forth in Section 4(a).

“Acquisition” has the meaning set forth in the Investment Agreement.

“Affiliate” means, as to any Person, any other Person that, directly or indirectly, controls, or is controlled by, or is under common control with, such Person; provided, however, (a) that the Company and its Subsidiaries shall not be deemed to be Affiliates of any Investor Party or any of its Affiliates, (b) portfolio companies in which any Investor Party or any of its Affiliates has an investment (whether as debt or equity) shall not be deemed an Affiliate of such Investor Party and (c) the Excluded True Wind Parties shall not be deemed to be Affiliates of any Investor Party, the Company or any of the Company’s Subsidiaries. For this purpose, “control” (including, with its correlative meanings, “controlled by” and “under common control with”) shall mean the possession, directly or indirectly, of the power to direct or cause the direction of management or policies of a Person, whether through the ownership of securities or partnership or other ownership interests, by contract or otherwise.

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“Articles of Incorporation” has the meaning set forth in the recitals above.

Any Person shall be deemed to “beneficially own”, to have “beneficial ownership” of, or to be “beneficially owning” any securities (which securities shall also be deemed “beneficially owned” by such Person) that such Person is deemed to “beneficially own” within the meaning of Rules 13d-3 and 13d-5 under the Exchange Act; provided that any Person shall be deemed to beneficially own any securities that such Person has the right to acquire, whether or not such right is exercisable within sixty (60) days or thereafter (including assuming conversion of all Series A Preferred Stock, if any, owned by such Person to Common Stock).

“Board” has the meaning set forth in the recitals above.

“Business Day” means any weekday that is not a day on which banking institutions in New York, New York are authorized or required by law, regulation or executive order to be closed.

“Bylaws” means the Second Amended and Restated Bylaws of the Company, as amended and as may be amended from time to time.

“Capital Stock” means, with respect to any Person, any and all shares of, interests in, rights to purchase, warrants to purchase, options for, participations in or other equivalents of or interests in (however designated) stock issued by such Person.

“Certificate of Designations” means this Certificate of Designations relating to the Series A Preferred Stock, as it may be amended from time to time.

“Change of Control” means the occurrence of one of the following, whether in a single transaction or a series of transactions:

(a) any “person” or “group” (as such terms are used in Sections 13(d) and 14(d) of the Exchange Act), is or becomes the “beneficial owner” (as defined in Rules 13d-3 and 13d-5 under the Exchange Act), directly or indirectly, of a majority of the total voting power of the Voting Stock of the Company, other than as a result of a transaction in which (1) the holders of securities that represented 100% of the Voting Stock of the Company immediately prior to such transaction are substantially the same as the holders of securities that represent a majority of the Voting Stock of the surviving Person or its Parent Entity immediately following such transaction and (2) the holders of securities that represented 100% of the Voting Stock of the Company immediately prior to such transaction own directly or indirectly Voting Stock of the surviving Person or its Parent Entity in substantially the same proportion to each other as immediately prior to such transaction;

(b) the merger or consolidation of the Company with or into another Person or the merger of another Person with or into the Company, or the sale, transfer or lease of all or substantially all the assets of the Company (determined on a consolidated basis), whether in a

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single transaction or a series of transactions, to another Person (other than to a Subsidiary or a Person that becomes a Subsidiary of the Company), or any recapitalization, reclassification or other transaction in which all or substantially all of the Common Stock is exchanged for or converted into cash, securities or other property, other than a transaction following which in the case of a merger or consolidation transaction, holders of securities that represented 100% of the Voting Stock of the Company immediately prior to such transaction own directly or indirectly (in substantially the same proportion to each other as immediately prior to such transaction, other than changes in proportionality as a result of any cash/stock election provided under the terms of the definitive agreement regarding such transaction) at least a majority of the voting power of the Voting Stock of the surviving Person in such merger or consolidation transaction immediately after such transaction; or

(c) shares of Common Stock or shares of any other Capital Stock into which the Series A Preferred Stock is convertible are not listed for trading on any United States national securities exchange or cease to be traded in contemplation of a de-listing (other than as a result of a transaction described in clause (b) above).

“close of business” means 5:00 p.m. (New York City time).

“Closing Price” of the Common Stock on any date of determination means the closing sale price or, if no closing sale price is reported, the last reported sale price, of the shares of the Common Stock on NASDAQ on such date. If the Common Stock is not traded on NASDAQ on any date of determination, the Closing Price of the Common Stock on such date of determination means the closing sale price as reported in the composite transactions for the principal United States securities exchange or automated quotation system on which the Common Stock is so listed or quoted, or, if no closing sale price is reported, the last reported sale price on the principal United States securities exchange or automated quotation system on which the Common Stock is so listed or quoted, or if the Common Stock is not so listed or quoted on a United States securities exchange or automated quotation system, the last quoted bid price for the Common Stock in the over-the-counter market as reported by OTC Markets Group Inc. or any similar organization, or, if that bid price is not available, the market price of the Common Stock on that date as determined by an Independent Financial Advisor retained by the Company for such purpose.

“Common Stock” has the meaning set forth in the recitals above.

“Company” has the meaning set forth in the recitals above.

“Constituent Person” has the meaning set forth in Section 12(a).

“Conversion Agent” means the Transfer Agent acting in its capacity as conversion agent for the Series A Preferred Stock, and its successors and assigns.

“Conversion Date” has the meaning set forth in Section 8(a).

“Conversion Notice” has the meaning set forth in Section 8(a)(i).

“Conversion Rate” means 166.11, subject to adjustment as set forth herein.

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“Conversion Restriction” has the meaning set forth in Section 6(c).

“Current Market Price” per share of Common Stock, as of any date of determination, means the arithmetic average of the VWAP per share of Common Stock for each of the ten (10) consecutive full Trading Days ending on the Trading Day immediately preceding such day, appropriately adjusted to take into account the occurrence during such period of any event described in Section 11.

“Debt Financing” has the meaning set forth in the Investment Agreement.

“Distributed Property” has the meaning set forth in Section 11(a)(iv).

“Distribution Transaction” means any distribution of equity securities of a Subsidiary of the Company to holders of Common Stock, whether by means of a spin-off, split-off, redemption, reclassification, exchange, stock dividend, share distribution, rights offering or similar transaction.

“EBITDA” shall mean, for purposes of this Certificate, “Consolidated Adjusted EBITDA” (or the substantially similar definition) as defined from time to time in, and calculated in accordance with, the primary credit facility of the Company and its Subsidiaries, provided that if the Company and its Subsidiaries do not have a primary credit facility that includes a definition of “Consolidated Adjusted EBITDA” (or a substantially similar definition), EBITDA shall be calculated by the Company in a manner consistent with its public disclosure of Adjusted EBITDA.

“Excess Amount” has the meaning set forth in Section 6(c).

“Exchange Act” means the Securities Exchange Act of 1934, as amended.

“Exchange Property” has the meaning set forth in Section 12(a).

“Excluded True Wind Parties” has the meaning set forth in the Investment Agreement.

“Expiration Date” has the meaning set forth in Section 11(a)(iii).

“Fall-Away of Investor Board Rights” has the meaning set forth in the Investment Agreement.

“Fair Market Value” means, with respect to any security or other property, the fair market value of such security or other property as reasonably determined in good faith by a majority of the Board, or an authorized committee thereof, which determination shall be made after consultation with an Independent Financial Advisor, as to any security or other property with a Fair Market Value of greater than $35,000,000.

“GAAP” shall mean generally accepted accounting principles in the United States.

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“Holder” means a Person in whose name the shares of the Series A Preferred Stock are registered, which Person shall be treated by the Company, Transfer Agent, Registrar, paying agent and Conversion Agent as the absolute owner of the shares of Series A Preferred Stock for the purpose of making payment and settling conversions and for all other purposes; provided that, to the fullest extent permitted by law, no Person that has received shares of Series A Preferred Stock in violation of the Investment Agreement shall be a Holder, the Transfer Agent, Registrar, paying agent and Conversion Agent, as applicable, shall not, unless directed otherwise by the Company, recognize any such Person as a Holder and the Person in whose name the shares of the Series A Preferred Stock were registered immediately prior to such transfer shall remain the Holder of such shares.

“Indebtedness” shall mean any indebtedness (including principal and premium) in respect of borrowed money.

“Independent Financial Advisor” means an accounting, appraisal, investment banking firm or consultant of nationally recognized standing; provided, however, that such firm or consultant is not an Affiliate of the Company.

“Investment Agreement” means that certain Investment Agreement between the Company and the Investor dated as of January 14, 2019, as it may be amended, supplemented or otherwise modified from time to time, with respect to certain terms and conditions concerning, among other things, the rights of and restrictions on the Holders.

“Investor” has the meaning set forth in the Investment Agreement.

“Investor Designee” means an individual nominated by the Board as a “Investor Designee” for election to the Board pursuant to Section 5.10(a), Section 5.10(d) or Section 5.10(e) of the Investment Agreement.

“Investor Parties” means the Investor and each Permitted Transferee of the Investor to whom shares of Series A Preferred Stock or Common Stock are transferred pursuant to Section 5.08(b)(i) of the Investment Agreement.

“Issuance Date” means, with respect to any share of Series A Preferred Stock, the date of issuance of such share.

“Junior Stock” has the meaning set forth in Section 2(c).

“Market Disruption Event” means any of the following events:

(a) any suspension of, or limitation imposed on, trading of the Common Stock by any exchange or quotation system on which the Closing Price is determined pursuant to the definition of the term “Closing Price” (the “Relevant Exchange”) during the one-hour period prior to the close of trading for the regular trading session on the Relevant Exchange (or for purposes of determining the VWAP per share of Common Stock, any period or periods aggregating one half-hour or longer during the regular trading session on the relevant day) and whether by reason of movements in price exceeding limits permitted by the Relevant Exchange as to securities generally, or otherwise relating to the Common Stock or options contracts relating to the Common Stock on the Relevant Exchange; or

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(b) any event that disrupts or impairs (as determined by the Company in its reasonable discretion) the ability of market participants during the one-hour period prior to the close of trading for the regular trading session on the Relevant Exchange (or for purposes of determining the VWAP per share of Common Stock, any period or periods aggregating one half-hour or longer during the regular trading session on the relevant day) in general to effect transactions in, or obtain market values for, the Common Stock on the Relevant Exchange or to effect transactions in, or obtain market values for, options contracts relating to the Common Stock on the Relevant Exchange.

“NASDAQ” means The Nasdaq Stock Market.

“Officer’s Certificate” means a certificate signed by the Chief Executive Officer, the Chief Financial Officer, the General Counsel or the Secretary of the Company.

“Original Issuance Date” means the Closing Date, as defined in the Investment Agreement.

“Parent Entity” means, with respect to any Person, any other Person of which such first Person is a direct or indirect wholly owned Subsidiary.

“Parity Stock” has the meaning set forth in Section 2(a).

“Participating Dividend” has the meaning set forth in Section 4(b).

“Permitted Transferee” means, with respect to any Person, (a) any Affiliate of such Person, (b) any successor entity of such Person and (c) with respect to any Person that is an investment fund, vehicle or similar entity, any other investment fund, vehicle or similar entity of which such Person or an Affiliate, advisor or manager of such Person serves as the general partner, manager or advisor.

“Person” means any individual, corporation, estate, partnership, joint venture, association, joint-stock company, limited liability company, trust, unincorporated organization or any other entity.

“Preferred Stock” has the meaning set forth in the recitals above.

“Rate of Accretion” means 8.0% per annum, or, to the extent and during the period with respect to which such rate has been adjusted as provided in Section 9(d), such adjusted rate.

“Record Date” means, with respect to any dividend, distribution or other transaction or event in which the holders of the Common Stock have the right to receive any cash, securities or other property or in which the Common Stock is exchanged for or converted into any combination of cash, securities or other property, the date fixed for determination of holders of the Common Stock entitled to receive such cash, securities or other property (whether such date is fixed by the Board or by statute, contract or otherwise).

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“Registrar” means the Transfer Agent acting in its capacity as registrar for the Series A Preferred Stock, and its successors and assigns.

“Relevant Exchange” has the meaning set forth in the definition of the term “Market Disruption Event”.

“Reorganization Event” has the meaning set forth in Section 12(a).

“Senior Stock” has the meaning set forth in Section 2(b).

“Series A Change of Control Redemption Price” means with respect to each share of Series A Preferred Stock then outstanding, the product of (a) the Accreted Value of such share as of the date of determination multiplied by (b) (i) 1.30 (if the Change of Control occurs before the first anniversary of the Original Issuance Date), (ii) 1.35 (if the Change of Control occurs on or after the first anniversary of the Original Issuance Date but before the second anniversary of the Original Issuance Date), (iii) 1.40 (if the Change of Control occurs on or after the second anniversary of the Original Issuance Date but before the third anniversary of the Original Issuance Date), (iv) 1.45 (if the Change of Control occurs on or after the third anniversary of the Original Issuance Date but before the fourth anniversary of the Original Issuance Date) and (v) 1.50 (if the Change of Control occurs on or after the fourth anniversary of the Original Issuance Date).

“Series A Preferred Stock” has the meaning set forth in Section 1.

“Series B Certificate” means that certain Certificate of Designations of Series B Preferred Stock of the Company dated as of the Original Issuance Date.

“Series B Preferred Stock” means the shares of Series B Convertible Preferred Stock, par value $1.00, of the Company issued on the Original Issuance Date.

“Share Cap” means a number of shares of Common Stock equal to (a) the product of (i) 0.199 and (ii) 54,186,180.

“Stated Value” means $1,000 per share of Series A Preferred Stock.

“Stockholder Approval” has the meaning set forth in the Investment Agreement.

“Stockholder Meeting” has the meaning set forth in the Investment Agreement.

“Subsidiary”, when used with respect to any Person, means any corporation, limited liability company, partnership, association, trust or other entity of which (a) securities or other ownership interests representing more than 50% of the ordinary voting power (or, in the case of a partnership, more than 50% of the general partnership interests) or (b) sufficient voting rights to elect at least a majority of the board of directors or other governing body are, as of such date, owned by such Person or one or more Subsidiaries of such Person or by such Person and one or more Subsidiaries of such Person.

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“Trading Day” means a Business Day on which the Relevant Exchange is scheduled to be open for business and on which there has not occurred a Market Disruption Event.

“Transfer Agent” means the Person acting as Transfer Agent, Registrar and paying agent and Conversion Agent for the Series A Preferred Stock, and its successors and assigns. The Transfer Agent initially shall be Computershare Trust Company, N.A.

“Trigger Event” has the meaning set forth in Section 11(a)(vii).

“Voting Stock” means (a) with respect to the Company, the Common Stock, the Series A Preferred Stock and any other Capital Stock of the Company having the right to vote generally in any election of directors of the Board and (b) with respect to any other Person, all Capital Stock of such Person having the right to vote generally in any election of directors of the board of directors of such Person or other similar governing body.

“VWAP” per share of Common Stock on any Trading Day means the per share volume-weighted average price as displayed under the heading Bloomberg VWAP on Bloomberg (or, if Bloomberg ceases to publish such price, any successor service reasonably chosen by the Company) page “ZIXI <equity> AQR” (or its equivalent successor if such page is not available) in respect of the period from the open of trading on the relevant Trading Day until the close of trading on such Trading Day (or if such volume-weighted average price is unavailable, the market price of one share of Common Stock on such Trading Day determined, using a volume-weighted average method, by an Independent Financial Advisor retained for such purpose by the Company).

SECTION 4. Accreted Value; Dividends. (a) Each share of Series A Preferred Stock will have an initial stated liquidation value equal to the Stated Value. From the Original Issuance Date, the Stated Value per share of Series A Preferred Stock will accrete at the Rate of Accretion, compounded quarterly on each March 31, June 30, September 30 and on December 31 of each year during which any shares of Series A Preferred Stock remain outstanding (each a “Quarterly Calculation Date”), beginning on the Quarterly Calculation Date immediately following the Original Issuance Date (the Stated Value per share as it has accreted as of any date, the “Accreted Value”, subject to appropriate adjustment in the event of any stock dividend, stock split, stock distribution or combination, consolidation, subdivision, reclassification or other corporate actions having the similar effect with respect to the Series A Preferred Stock). All calculations of Accreted Value will be computed on the basis of a 360-day year of twelve 30-day months. Notwithstanding the foregoing, each share of Series A Preferred Stock issued in connection with the conversion of shares of Series B Preferred Stock in accordance with the terms of the Series B Preferred Stock shall be deemed to have the same Accreted Value as of the date such share of Series A Preferred Stock is issued (the “Conversion Date”) as the Accreted Value as of the Conversion Date of a share of Series A Preferred stock that was issued on the Original Issuance Date.

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(b) Participating Dividends. The Holders shall also be entitled to receive, when, as and if declared by the Board, dividends per share of Series A Preferred Stock of an amount equal to the aggregate amount of any dividends or other distributions, whether cash, in kind or other property (including, for the avoidance of doubt, any securities), paid on outstanding shares of Common Stock on a per share basis based on the number of shares of Common Stock into which such share of Series A Preferred Stock could be converted on the applicable record date for such dividends or other distributions, assuming such shares of Common Stock were outstanding on the applicable record date for such dividend or other distributions (the “Participating Dividends”). Participating Dividends shall be payable as and when paid to the holders of shares of Common Stock. Participating Dividends are payable on a cumulative basis once declared, whether or not there shall be funds legally available for the payment thereon. The Company shall not declare or pay any dividends on shares of Common Stock unless the holders of the Series A Preferred Stock then outstanding shall simultaneously receive Participating Dividends on a pro rata basis as if the shares of Series A Preferred Stock had been converted into shares of Common Stock immediately prior to the record date for determining the stockholders eligible to receive such dividends. If the Company distributes any rights pursuant to any stockholder rights plan on or after the date hereof, then such distribution will not require a Participating Dividend except to the extent provided in the immediately following sentence. If any shares of Common Stock are issued upon conversion of any share of Series A Preferred Stock and, at the time of such conversion, the Company has in effect any stockholder rights plan, then the holder of such share of Series A Preferred Stock will be entitled to receive, in addition to, and concurrently with the delivery of, the consideration otherwise payable under this Certificate of Designations upon such conversion, the rights set forth in such stockholder rights plan, unless such rights have separated from the shares of Common Stock at such time, in which case such separation will require, at the time of such separation, a Participating Dividend pursuant to this Section 4(b).

SECTION 5. Liquidation Rights. (a) Liquidation. In the event of any voluntary or involuntary liquidation, dissolution or winding up of the affairs of the Company, the Holders shall be entitled, out of assets legally available therefor, before any distribution or payment out of the assets of the Company may be made to or set aside for the holders of any Junior Stock, and subject to the rights of the holders of any Senior Stock or Parity Stock and the rights of the Company’s existing and future creditors, to receive in full a liquidating distribution in cash and in the amount per share of Series A Preferred Stock equal to the greater of (i) the Accreted Value with respect to such share of Series A Preferred Stock as of the date of such voluntary or involuntary liquidation, dissolution or winding up of the affairs of the Company and (ii) the amount such Holders would have received had such Holders, immediately prior to such voluntary or involuntary liquidation, dissolution or winding up of the affairs of the Company, converted such shares of Series A Preferred Stock into Common Stock (pursuant to Section 6 without regard to any of the limitations on convertibility contained therein). Holders shall not be entitled to any further payments in the event of any such voluntary or involuntary liquidation, dissolution or winding up of the affairs of the Company other than what is expressly provided for in this Section 5 and will have no right or claim to any of the Company’s remaining assets.

(b) Partial Payment. If in connection with any distribution described in Section 5(a) above, the assets of the Company or proceeds therefrom are not sufficient to pay in full the aggregate liquidating distributions required to be paid pursuant to Section 5(a) to all

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Holders and the liquidating distributions payable all holders of any Parity Stock, the amounts distributed to the Holders and to the holders of all such Parity Stock shall be paid pro rata in accordance with the respective aggregate liquidating distributions to which they would otherwise be entitled if all amounts payable thereon were paid in full.

(c) Merger, Consolidation and Sale of Assets Not Liquidation. For purposes of this Section 5, the sale, conveyance, exchange or transfer (for cash, shares of stock, securities or other consideration) of all or substantially all of the property and assets of the Company shall not be deemed a voluntary or involuntary liquidation, dissolution or winding up of the affairs of the Company, nor shall the merger, consolidation, statutory exchange or any other business combination transaction of the Company into or with any other Person or the merger, consolidation, statutory exchange or any other business combination transaction of any other Person into or with the Company be deemed to be a voluntary or involuntary liquidation, dissolution or winding up of the affairs of the Company.

SECTION 6. Right of the Holders to Convert.

(a) Each Holder shall have the right, at such Holder’s option, subject to the conversion procedures set forth in Section 8, to convert each share of such Holder’s Series A Preferred Stock at any time into (i) the number of shares of Common Stock equal to the product of (A) the Accreted Value with respect to such share of Series A Preferred Stock as of the applicable Conversion Date multiplied by (B) the Conversion Rate as of the applicable Conversion Date divided by (C) 1,000 plus (ii) cash in lieu of fractional shares as set out in Section 11(h). The right of conversion may be exercised as to all or any portion of such Holder’s Series A Preferred Stock from time to time; provided that, in each case, no right of conversion may be exercised by a Holder in respect of fewer than 1,000 shares of Series A Preferred Stock (unless such conversion relates to all shares of Series A Preferred Stock held by such Holder).

(b) The Company shall at all times reserve and keep available out of its authorized and unissued Common Stock, solely for issuance upon the conversion of the Series A Preferred Stock, such number of shares of Common Stock as shall from time to time be issuable upon the conversion of all the shares of Series A Preferred Stock then outstanding. Any shares of Common Stock issued upon conversion of Series A Preferred Stock shall be duly authorized, validly issued, fully paid and nonassessable.

(c) Notwithstanding the foregoing or anything else in this Certificate of Designations to the contrary, unless and until the Stockholder Approval is obtained, the Holders shall not have the right to convert their shares of Series A Preferred Stock into shares of Common Stock pursuant to the terms of this Certificate of Designation, and the Company shall not be required to issue shares of Common Stock pursuant to such conversion, in excess of the Share Cap (the “Conversion Restriction”); and the Company shall either obtain Stockholder Approval of such issuances or deliver, in lieu of any shares of Common Stock otherwise deliverable upon conversion in excess of the Conversion Restriction, an amount of cash per share equal to the VWAP per share of Common Stock on the Trading Day immediately preceding the Conversion Date (such cash amount, the “Excess Amount”). For the avoidance of doubt, when the Stockholder Approval is obtained, this Section 6(c) shall be deemed deleted in its entirety.

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SECTION 7. [Reserved].

SECTION 8. Conversion Procedures and Effect of Conversion. (a) Conversion Procedure. A Holder must do each of the following in order to convert shares of Series A Preferred Stock pursuant to this Section 8(a):

(i) in the case of a conversion pursuant to Section 6(a), complete and manually sign the conversion notice provided by the Conversion Agent (the “Conversion Notice”), and deliver such notice to the Conversion Agent; provided that a Conversion Notice may be conditional on the completion of a Change of Control or other corporate transaction;

(ii) deliver to the Conversion Agent the certificate or certificates (if any) representing the shares of Series A Preferred Stock to be converted;

(iii) if required, furnish appropriate endorsements and transfer documents; and

(iv) if required, pay any stock transfer, documentary, stamp or similar taxes not payable by the Company pursuant to Section 21.

The “Conversion Date” means with respect to conversion of any shares of Series A Preferred Stock at the option of any Holder pursuant to Section 6(a), the date on which such Holder complies with the procedures in this Section 8(a) (including the satisfaction of any conditions to conversion set forth in the Conversion Notice).

(b) Effect of Conversion. Effective immediately prior to the close of business on the Conversion Date applicable to any shares of Series A Preferred Stock, Participating Dividends shall no longer be declared on any such shares of Series A Preferred Stock, and such shares of Series A Preferred Stock shall cease to be outstanding.

(c) Record Holder of Underlying Securities as of Conversion Date. The Person or Persons entitled to receive the Common Stock and, to the extent applicable, cash, securities or other property issuable upon conversion of Series A Preferred Stock on a Conversion Date shall be treated for all purposes as the record holder(s) of such shares of Common Stock and/or cash, securities or other property as of the close of business on such Conversion Date. As promptly as practicable on or after the Conversion Date and compliance by the applicable Holder with the relevant procedures contained in Section 8(a) (and in any event no later than three (3) Trading Days thereafter; provided, however, that, if a written notice from the Holder in accordance with Section 8(a) specifies a date of delivery for any shares of Common Stock, such shares shall be delivered on the date so specified, which shall be no earlier than the second Business Day immediately following the date of such notice and no later than the seventh Business Day thereafter), the Company shall issue the number of whole shares of Common Stock issuable upon conversion (and deliver payment of cash in lieu of fractional shares as set out in Section 11(h) and any Excess Amount) and, to the extent applicable, any cash, securities or other property issuable thereon. Such delivery of shares of Common Stock, securities or other property shall be made by book-entry or, at the request of the Holder, through the facilities of The Depositary Trust Company or in certificated form. Any such certificate or certificates shall be delivered by the Company to the appropriate Holder on a book-entry basis, through the facilities of The Depositary Trust Company, or by mailing certificates evidencing the shares to

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the Holders, in each case at their respective addresses as set forth in the Conversion Notice (in the case of a conversion pursuant to Section 6(a)). In the event that a Holder shall not by written notice designate the name in which shares of Common Stock (and payments of cash in lieu of fractional shares) and, to the extent applicable, cash, securities or other property to be delivered upon conversion of shares of Series A Preferred Stock should be registered or paid, or the manner in which such shares, cash, securities or other property should be delivered, the Company shall be entitled to register and deliver such shares, securities or other property, and make such payment, in the name of the Holder and in the manner shown on the records of the Company.

(d) Status of Converted or Reacquired Shares. Shares of Series A Preferred Stock converted in accordance with this Certificate of Designations, or otherwise acquired by the Company in any manner whatsoever, shall be retired promptly after the conversion or acquisition thereof. All such shares shall, upon their retirement and any filing required by the Texas Business Organizations Code, become authorized but unissued shares of Preferred Stock, without designation as to series until such shares are once more designated as part of a particular series by the Board pursuant to the provisions of the Articles of Incorporation.

SECTION 9. Change of Control.

(a) Subject to Section 9(d), upon the occurrence of a Change of Control, the Company shall be required to redeem the outstanding shares of Series A Preferred Stock at a redemption price per share of Series A Preferred Stock, payable in cash, equal to the greater of (i) the Series A Change of Control Redemption Price of such share of Series A Preferred Stock and (ii) (A) the amount of cash such Holder would have received plus (B) the Fair Market Value of any other assets in each case had such Holder, immediately prior to such Change of Control, converted such share of Series A Preferred Stock into Common Stock pursuant to Section 6 without regard to any of the limitations on convertibility contained therein (the “Change of Control Redemption Price”).

(b) Initial Change of Control Notice. On or before the twentieth (20th) Business Day prior to the date on which the Company anticipates consummating a Change of Control (or, if later, promptly after the Company discovers that a Change of Control may occur), a written notice (a “Change of Control Notice”) shall be sent by or on behalf of the Company to the Holders as they appear in the records of the Company, which notice shall contain the date on which the Change of Control is anticipated to be effected (or, if applicable, the date on which a Schedule TO or other schedule, form or report disclosing a Change of Control was filed). The Change of Control Notice shall include (i) a description of the material terms and conditions of the Change of Control, (ii) the date on which the Change of Control is anticipated to be consummated, (iii) the Change of Control Redemption Price and the calculation thereof and (iv) the instructions a Holder must follow to receive payment.

(c) Delivery upon Change of Control. Upon the consummation of a Change of Control, subject to Section 9(d), the Company (or its successor) shall deliver or cause to be delivered to the Holder by wire transfer the Change of Control Redemption Price of such Holder’s shares of Series A Preferred Stock.

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(d) Sufficient Funds. If the Company shall not have sufficient funds legally available under the Texas Business Organizations Code to redeem all outstanding shares of Series A Preferred Stock if it redeems outstanding shares of Series A Preferred Stock, the Company shall (i) redeem, pro rata among the Holders, a number of shares of Series A Preferred Stock with an aggregate Change of Control Redemption Price equal to the amount legally available for the redemption of shares of Series A Preferred Stock under the Texas Business Organizations Code and (ii) redeem any shares of Series A Preferred Stock not purchased because of the foregoing limitations at the applicable Change of Control Redemption Price as soon as practicable after the Company is able to make such redemption out of assets legally available for the purchase of such share of Series A Preferred Stock. The inability of the Company (or its successor) to make a redemption payment for any reason shall not relieve the Company (or its successor) from its obligation to effect any required purchase when, as and if permitted by applicable law. If the Company fails to pay the Change of Control Redemption Price in full when due in accordance with this Section 9 in respect of some or all of the shares of Series A Preferred Stock to be redeemed pursuant to this Section 9, the Rate of Accretion on such shares repurchased shall equal 10.0% per annum, which shall then increase by 0.50% on every three-month anniversary after such failure (but not, in any event, to greater than 12.0% per annum. Notwithstanding the foregoing, if a Change of Control occurs at a time when the Company is restricted or prohibited from redeeming some or all of the Series A Preferred Stock, the Company will use its commercially reasonable efforts to obtain the requisite consents to remove or obtain an exception or waiver to such restrictions or prohibition. Nothing herein shall limit a Holder’s right to pursue any other remedies available to it hereunder, at law or in equity, including, without limitation, a decree of specific performance and/or injunctive relief with respect to the Company’s failure to comply with its obligations under the Section 9.

(e) Change of Control Agreements. The Company shall not enter into any agreement for a transaction constituting a Change of Control unless (i) such agreement provides for or does not interfere with or prevent (as applicable) the payment in full of the Change of Control Redemption Price pursuant to this Section 9 and (ii) the acquiring or surviving Person in such Change of Control represents or covenants, in form and substance reasonably satisfactory to the Board acting in good faith, that at the closing of such Change of Control, such Person shall have sufficient funds (which may include, without limitation, cash and cash equivalents on the Company’s balance sheet, the proceeds of any debt or equity financing, available lines of credit or uncalled capital commitments) to consummate such Change of Control and effect the payment of the Change of Control Redemption Price in respect of the outstanding shares of Series A Preferred Stock.

(f) Partial Redemption. In case any certificate for shares of Series A Preferred Stock shall be surrendered for partial redemption, the Company shall execute and deliver to or upon the written order of the Holder of the certificate so surrendered a new certificate for the shares of Series A Preferred Stock not redeemed.

(g) Effect of Redemption. Effective immediately prior to the close of business on the Redemption Date for any shares of Series A Preferred Stock redeemed pursuant to this Section 9, Participating Dividends shall no longer be declared on any such shares of Series A Preferred Stock, and such shares of Series A Preferred Stock shall cease to be outstanding.

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(h) Status of Redeemed Shares. Shares of Series A Preferred Stock redeemed in accordance with this Section 9, shall return to the status of and constitute authorized but unissued shares of Preferred Stock, without classification as to series until such shares are once more classified as a particular series by the Board pursuant to the provisions of the Articles of Incorporation.

SECTION 10. Optional Redemption. (a) The Series A Preferred Stock may be redeemed in whole, but not in part, for cash at any time after the fourth anniversary of the Original Issuance Date, at the option of the Company, upon giving notice of redemption pursuant to Section 10(b), at a redemption price per share equal to the product of (A) the Accreted Value per share of the Series A Preferred Stock to be redeemed as of the applicable Redemption Date multiplied by (B) 1.50.

(b) Notice of every redemption of shares of Series A Preferred Stock pursuant to Section 10(a)(i) shall be mailed, postage prepaid, addressed to the Holders of record of the shares to be redeemed at their respective last addresses appearing on the books of the Company, or given by electronic communication in compliance with the provisions of the Texas Business Organizations Code. Such mailing or electronic transmission shall be at least 30 days and not more than 60 days before the date fixed for redemption. Any notice made as provided in this Section 10(b) shall be conclusively presumed to have been duly given upon such mailing or electronic transmission, whether or not the Holder receives such notice, but failure duly to give such notice as provided in this Section 10(b), or any defect in such notice or in the mailing or electronic transmission thereof, to any Holder of shares of Series A Preferred Stock designated for redemption shall not affect the validity of the proceedings for the redemption of any other shares of Series A Preferred Stock. Each notice of redemption given to a Holder shall state: (1) the redemption date; (2) the number of shares of the Series A Preferred Stock to be redeemed and, if less than all the shares held by such Holder are to be redeemed, the number of such shares to be redeemed from such Holder; (3) the redemption price; and (4) the place or places where certificates for such shares are to be surrendered for payment of the redemption price.

SECTION 11. Anti-Dilution Adjustments. (a) Adjustments. The Conversion Rate will be subject to adjustment, without duplication, upon the occurrence of the following events, except that the Company shall not make any adjustment to the Conversion Rate if Holders of the Series A Preferred Stock participate, at the same time and upon the same terms as holders of Common Stock and solely as a result of holding shares of Series A Preferred Stock, in any transaction described in this Section 11(a), without having to convert their Series A Preferred Stock, as if they held a number of shares of Common Stock equal to the product of (x) Accreted Value of the shares of Series A Preferred Stock held by such Holders multiplied by (y) the Conversion Rate divided by (z) 1,000:

(i) The issuance of Common Stock as a dividend or distribution to all or substantially all holders of Common Stock, or a subdivision or combination of Common Stock or a reclassification of Common Stock into a greater or lesser number of shares of Common Stock, in which event the Conversion Rate shall be adjusted based on the following formula:

CR₁ = CR₀ x (OS₁ / OS₀)

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CR₀ = the Conversion Rate in effect immediately prior to the close of business on (i) the Record Date for such dividend or distribution, or (ii) the effective date of such subdivision, combination or reclassification

CR₁ = the new Conversion Rate in effect immediately after the close of business on (i) the Record Date for such dividend or distribution, or (ii) the effective date of such subdivision, combination or reclassification

OS₀ = the number of shares of Common Stock outstanding immediately prior to the close of business on (i) the Record Date for such dividend or distribution or (ii) the effective date of such subdivision, combination or reclassification

OS₁ = the number of shares of Common Stock that would be outstanding immediately after, and solely as a result of, the completion of such event

Any adjustment made pursuant to this clause (i) shall be effective immediately after the close of business on the Record Date for such dividend or distribution, or the effective date of such subdivision, combination or reclassification. If any such event is announced or declared but does not occur, the Conversion Rate shall be readjusted, effective as of the date the Board announces that such event shall not occur, to the Conversion Rate that would then be in effect if such event had not been declared.

(ii) The dividend, distribution or other issuance to all or substantially all holders of Common Stock of rights (other than rights, options or warrants distributed in connection with a stockholder rights plan (in which event the provisions of Section 11(a)(vii) shall apply)), options or warrants entitling them to subscribe for or purchase shares of Common Stock for a period expiring forty-five (45) days or less from the date of issuance thereof, at a price per share that is less than the Current Market Price as of the Record Date for such issuance, in which event the Conversion Rate will be increased based on the following formula:

CR₁ = CR₀ x [(OS₀+X) / (OS₀+Y)]

CR₀ = the Conversion Rate in effect immediately prior to the close of business on the Record Date for such dividend, distribution or issuance

CR₁ = the new Conversion Rate in effect immediately following the close of business on the Record Date for such dividend, distribution or issuance

OS₀ = the number of shares of Common Stock outstanding immediately prior to the close of business on the Record Date for such dividend, distribution or issuance

X = the total number of shares of Common Stock issuable pursuant to such rights, options or warrants

Y = the number of shares of Common Stock equal to the aggregate price payable to exercise such rights, options or warrants divided by the Current Market Price as of the Record Date for such dividend, distribution or issuance.

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For purposes of this clause (ii), in determining whether any rights, options or warrants entitle the holders to purchase the Common Stock at a price per share that is less than the Current Market Price as of the Record Date for such dividend, distribution or issuance, there shall be taken into account any consideration the Company receives for such rights, options or warrants, and any amount payable on exercise thereof, with the value of such consideration, if other than cash, to be the Fair Market Value thereof.

Any adjustment made pursuant to this clause (ii) shall become effective immediately following the close of business on the Record Date for such dividend, distribution or issuance. In the event that such rights, options or warrants are not so issued, the Conversion Rate shall be readjusted, effective as of the date the Board publicly announces its decision not to issue such rights, options or warrants, to the Conversion Rate that would then be in effect if such dividend, distribution or issuance had not been declared. To the extent that such rights, options or warrants are not exercised prior to their expiration or shares of Common Stock are otherwise not delivered pursuant to such rights, options or warrants upon the exercise of such rights, options or warrants, the Conversion Rate shall be readjusted to the Conversion Rate that would then be in effect had the adjustments made upon the dividend, distribution or issuance of such rights, options or warrants been made on the basis of the delivery of only the number of shares of Common Stock actually delivered.

(iii) The Company or one or more of its Subsidiaries purchases Common Stock pursuant to a tender offer or exchange offer (other than an exchange offer that constitutes a Distribution Transaction subject to Section 11(a)(v)) by the Company or a Subsidiary of the Company for all or any portion of the Common Stock, or otherwise acquires Common Stock (except (1) in an open market purchase in compliance with Rule 10b-18 promulgated under the Exchange Act, (2) through an “accelerated share repurchase” on customary terms or (3) in connection with tax withholding upon vesting or settlement of options, restricted stock units, performance share units or other similar equity awards or upon forfeiture or cashless exercise of options or other equity awards) (a “Covered Repurchase”), if the cash and value of any other consideration included in the payment per share of Common Stock validly tendered, exchanged or otherwise acquired through a Covered Repurchase exceeds the arithmetic average of the VWAP per share of Common Stock for each of the ten (10) consecutive full Trading Days commencing on, and including, the Trading Day next succeeding the last day on which tenders or exchanges may be made pursuant to such tender or exchange offer (as it may be amended) or shares of Common Stock are otherwise acquired through a Covered Repurchase (the “Expiration Date”), in which event the Conversion Rate shall be increased based on the following formula:

CR₁ = CR₀ x [(FMV + (SP₁ x OS₁))] / (SP₁ x OS₀)

CR₀ = the Conversion Rate in effect immediately prior to the close of business on the Expiration Date

CR₁ = the new Conversion Rate in effect immediately after the close of business on the Expiration Date

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FMV = the Fair Market Value, on the Expiration Date, of all cash and any other consideration paid or payable for all shares validly tendered or exchanged and not withdrawn, or otherwise acquired through a Covered Repurchase, as of the Expiration Date

OS₀ = the number of shares of Common Stock outstanding immediately prior to the last time tenders or exchanges may be made pursuant to such tender or exchange offer (including the shares to be purchased in such tender or exchange offer) or shares are otherwise acquired through a Covered Repurchase

OS₁ = the number of shares of Common Stock outstanding immediately after the last time tenders or exchanges may be made pursuant to such tender or exchange offer (after giving effect to the purchase of shares in such tender or exchange offer) or shares are otherwise acquired through a Covered Repurchase

SP₁ = the arithmetic average of the VWAP per share of Common Stock for each of the ten (10) consecutive full Trading Days commencing on, and including, the Trading Day next succeeding the Expiration Date

Such adjustment shall become effective immediately after the close of business on the Expiration Date. If an adjustment to the Conversion Rate is required under this Section 11(a)(iii), delivery of any additional shares of Common Stock that may be deliverable upon conversion as a result of an adjustment required under this Section 11(a)(iii) shall be delayed to the extent necessary in order to complete the calculations provided for in this Section 11(a)(iii).

In the event that the Company or any of its Subsidiaries is obligated to purchase Common Stock pursuant to any such tender offer, exchange offer or other commitment to acquire shares of Common Stock through a Covered Repurchase but is permanently prevented by applicable law from effecting any such purchases, or all such purchases are rescinded, then the Conversion Rate shall be readjusted to be the Conversion Rate that would have been then in effect if such tender offer, exchange offer or Covered Repurchase had not been made.

(iv) The Company shall, by dividend or otherwise, distribute to all or substantially all holders of its Common Stock (other than for cash in lieu of fractional shares), shares of any class of its Capital Stock, evidences of its Indebtedness, assets, other property or securities, but excluding (A) dividends or distributions referred to in Section 11(a)(i) or Section 11(a)(ii) hereof, (B) Distribution Transactions as to which Section 11(a)(v) shall apply, (C) dividends or distributions paid exclusively in cash as to which Section 11(a)(vi) shall apply and (D) rights, options or warrants distributed in connection with a stockholder rights plan as to which Section 11(a)(vii) shall apply (any of such shares of its Capital Stock, Indebtedness, assets or property that are not so excluded are hereinafter called the “Distributed Property”), then, in each such case the Conversion Rate shall be increased based on the following formula:

CR₁ = CR₀ x [SP₀ / (SP₀ – FMV)]

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CR₀ = the Conversion Rate in effect immediately prior to the close of business on the Record Date for such dividend or distribution

CR₁ = the new Conversion Rate in effect immediately after the close of business on the Record Date for such dividend or distribution

SP₀ = the Current Market Price as of the Record Date for such dividend or distribution

FMV = the Fair Market Value of the portion of Distributed Property distributed with respect to each outstanding share of Common Stock on the Record Date for such dividend or distribution; provided that, if FMV is equal or greater than SP₀, then in lieu of the foregoing adjustment, the Company shall distribute to each holder of Series A Preferred Stock on the date the applicable Distributed Property is distributed to holders of Common Stock, but without requiring such holder to convert its shares of Series A Preferred Stock, in respect of each share of Series A Preferred Stock held by such holder, the amount of Distributed Property such holder would have received had such holder owned a number of shares of Common Stock equal to the Conversion Rate on the Record Date for such dividend or distribution

Any adjustment made pursuant to this clause (iv) shall be effective immediately after the close of business on the Record Date for such dividend or distribution. If any such dividend or distribution is declared but does not occur, the Conversion Rate shall be readjusted, effective as of the date the Board announces that such dividend or distribution shall not occur, to the Conversion Rate that would then be in effect if such dividend or distribution had not been declared.

(v) The Company effects a Distribution Transaction, in which case the Conversion Rate in effect immediately prior to the effective date of the Distribution Transaction shall be increased based on the following formula:

CR₁ = CR₀ x [(FMV + MP₀) / MP₀]

CR₀ = the Conversion Rate in effect immediately prior to the close of business on the effective date of the Distribution Transaction

CR₁ = the new Conversion Rate in effect immediately after the close of business on the effective date of the Distribution Transaction

FMV = the arithmetic average of the volume-weighted average prices for a share of the capital stock or other interest distributed to holders of Common Stock on the principal United States securities exchange or automated quotation system on which such capital stock or other interest trades, as reported by Bloomberg (or, if Bloomberg ceases to publish such price, any successor service chosen by the Company) in respect of the period from the open of trading on the relevant Trading Day until the close of trading on such Trading Day (or if such volume-weighted average price is unavailable, the market price of one share of such capital stock or other interest on such Trading Day determined, using a volume-weighted average method, by an Independent Financial Advisor retained for such purpose by the Company), for each of the ten consecutive full Trading Days commencing with, and including, the effective date of the Distribution Transaction

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MP₀ = the arithmetic average of the VWAP per share of Common Stock for each of the ten (10) consecutive full Trading Days commencing on, and including, the effective date of the Distribution Transaction

Such adjustment shall become effective immediately following the close of business on the effective date of the Distribution Transaction. If an adjustment to the Conversion Rate is required under this Section 11(a)(v), delivery of any additional shares of Common Stock that may be deliverable upon conversion as a result of an adjustment required under this Section 11(a)(v) shall be delayed to the extent necessary in order to complete the calculations provided for in this Section 11(a)(v).

(vi) The Company makes a cash dividend or distribution to all or substantially all holders of the Common Stock, the Conversion Rate shall be increased based on the following formula:

CR₁ = CR₀ x [SP₀ / (SP₀ – C)]

CR₀ = the Conversion Rate in effect immediately prior to the close of business on the Record Date for such dividend or distribution

CR₁ = the new Conversion Rate in effect immediately after the close of business on the Record Date for such dividend or distribution

SP₀ = the Current Market Price as of the Record Date for such dividend or distribution

C = the amount in cash per share of Common Stock the Company distributes to all or substantially all holders of its Common Stock; provided that, if C is equal or greater than SP₀, then in lieu of the foregoing adjustment, the Company shall pay to each holder of Series A Preferred Stock on the date the applicable cash dividend or distribution is made to holders of Common Stock, but without requiring such holder to convert its shares of Series A Preferred Stock, in respect of each share of Series A Preferred Stock held by such holder, the amount of cash such holder would have received had such holder owned a number of shares of Common Stock equal to the Conversion Rate on the Record Date for such dividend or distribution

Any adjustment made pursuant to this clause (vi) shall be effective immediately after the close of business on the Record Date for such dividend or distribution. If any dividend or distribution is declared but not paid, the Conversion Rate shall be readjusted, effective as of the date the Board announces that such dividend or distribution will not be paid, to the Conversion Rate that would then be in effect if such had dividend or distribution not been declared.

(vii) If the Company has a stockholder rights plan in effect with respect to the Common Stock on any Conversion Date, upon conversion of any shares of the Series A Preferred Stock, Holders of such shares will receive, in addition to the applicable number of shares of Common Stock, the rights under such rights plan relating to such Common Stock, unless, prior to such Conversion Date, the rights have (i) become exercisable or (ii) separated from the shares of Common Stock (the first of such events to occur, a

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“Trigger Event”), in which case, the Conversion Rate will be adjusted, effective automatically at the time of such Trigger Event, as if the Company had made a distribution of such rights to all holders of the Company Common Stock as described in Section 11(a)(ii) (without giving effect to the forty-five (45) day limit on the exercisability of rights, options or warrants ordinarily subject to such Section 11(a)(ii)), subject to appropriate readjustment in the event of the expiration, termination or redemption of such rights prior to the exercise, deemed exercise or exchange thereof. Notwithstanding the foregoing, to the extent any such stockholder rights are exchanged by the Company for shares of Common Stock or other property or securities, the Conversion Rate shall be appropriately readjusted as if such stockholder rights had not been issued, but the Company had instead issued such shares of Common Stock or other property or securities as a dividend or distribution of shares of Common Stock pursuant to Section 11(a)(i) or Section 11(a)(iv), as applicable.

To the extent that such rights are not exercised prior to their expiration, termination or redemption, the Conversion Rate shall be readjusted to the Conversion Rate that would then be in effect had the adjustments made upon the occurrence of the Trigger Event been made on the basis of the issuance of, and the receipt of the exercise price with respect to, only the number of shares of Common Stock actually issued pursuant to such rights.

Notwithstanding anything to the contrary in this Section 11(a)(vii), no adjustment shall be required to be made to the Conversion Rate with respect to any Holder which is, or is an “affiliate” or “associate” of, an “acquiring person” under such stockholder rights plan or with respect to any direct or indirect transferee of such Holder who receives Series A Preferred Stock in such transfer after the time such Holder becomes, or its affiliate or associate becomes, such an “acquiring person”.

(b) Calculation of Adjustments. All adjustments to the Conversion Rate shall be calculated by the Company to the nearest 1/10,000th of one share of Common Stock (or if there is not a nearest 1/10,000th of a share, to the next lower 1/10,000th of a share). No adjustment to the Conversion Rate will be required unless such adjustment would require an increase or decrease of at least one percent of the Conversion Rate; provided, however, that any such adjustment that is not required to be made will be carried forward and taken into account in any subsequent adjustment; provided, further, that any such adjustment of less than one percent that has not been made will be made upon any Conversion Date or redemption or repurchase date.

(c) When No Adjustment Required. (i) Except as otherwise provided in this Section 11, the Conversion Rate will not be adjusted for the issuance of Common Stock or any securities convertible into or exchangeable for Common Stock or carrying the right to purchase any of the foregoing, for the repurchase of Common Stock or to the extent that an adjustment would be duplicative because an equivalent Participating Dividend was distributed to the Holders.

(ii) Except as otherwise provided in this Section 11, the Conversion Rate will not be adjusted as a result of the issuance of, the distribution of separate certificates representing, the exercise or redemption of, or the termination or invalidation of, rights pursuant to any stockholder rights plans.

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(iii) No adjustment to the Conversion Rate will be made:

(A) upon the issuance of any shares of Common Stock pursuant to any present or future plan providing for the reinvestment of dividends or interest payable on securities of the Company and the investment of additional optional amounts in Common Stock under any plan in which purchases are made at market prices on the date or dates of purchase, without discount, and whether or not the Company bears the ordinary costs of administration and operation of the plan, including brokerage commissions;

(B) upon the issuance of any shares of Common Stock or options or rights to purchase such shares pursuant to any present or future employee, director or consultant benefit plan or program of or assumed by the Company or any of its Subsidiaries or of any employee agreements or arrangements or programs;

(C) upon the issuance of any shares of Common Stock pursuant to any option, warrant, right, or exercisable, exchangeable or convertible security, including the Series A Preferred Stock; or

(D) for a change in the par value of the Common Stock.

(d) Successive Adjustments. After an adjustment to the Conversion Rate under this Section 11, any subsequent event requiring an adjustment under this Section 11 shall cause an adjustment to each such Conversion Rate as so adjusted.

(e) Multiple Adjustments. For the avoidance of doubt, if an event occurs that would trigger an adjustment to the Conversion Rate pursuant to this Section 11 under more than one subsection hereof, such event, to the extent fully taken into account in a single adjustment, shall not result in multiple adjustments hereunder; provided, however, that if more than one subsection of this Section 11 is applicable to a single event, the subsection shall be applied that produces the largest adjustment.

(f) Notice of Adjustments. Whenever the Conversion Rate is adjusted as provided under this Section 11, the Company shall as soon as reasonably practicable following the occurrence of an event that requires such adjustment (or if the Company is not aware of such occurrence, as soon as reasonably practicable after becoming so aware):

(i) compute the adjusted applicable Conversion Rate in accordance with this Section 11 and prepare and transmit to the Conversion Agent an Officer’s Certificate setting forth the applicable Conversion Rate, the method of calculation thereof, and the facts requiring such adjustment and upon which such adjustment is based; and

(ii) provide a written notice to the Holders of the occurrence of such event and a statement in reasonable detail setting forth the method by which the adjustment to the applicable Conversion Rate was determined and setting forth the adjusted applicable Conversion Rate.

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(g) Conversion Agent. The Conversion Agent shall not at any time be under any duty or responsibility to any Holder to determine whether any facts exist that may require any adjustment of the Conversion Rate or with respect to the nature or extent or calculation of any such adjustment when made, or with respect to the method employed in making the same. The Conversion Agent shall be fully authorized and protected in relying on any Officer’s Certificate delivered pursuant to this Section 11(g) and any adjustment contained therein and the Conversion Agent shall not be deemed to have knowledge of any adjustment unless and until it has received such certificate. The Conversion Agent shall not be accountable with respect to the validity or value (or the kind or amount) of any shares of Common Stock, or of any securities or property, that may at the time be issued or delivered with respect to any Series A Preferred Stock and the Conversion Agent makes no representation with respect thereto. The Conversion Agent shall not be responsible for any failure of the Company to issue, transfer or deliver any shares of Common Stock pursuant to the conversion of Series A Preferred Stock or to comply with any of the duties, responsibilities or covenants of the Company contained in this Section 11.

(h) Fractional Shares. No fractional shares of Common Stock will be delivered to the Holders upon conversion. In lieu of fractional shares otherwise issuable, the Holders will be entitled to receive, at the Company’s sole discretion, either (i) an amount in cash equal to the fraction of a share of Common Stock multiplied by the Closing Price of the Common Stock on the Trading Day immediately preceding the applicable Conversion Date or (ii) one additional whole share of Common Stock. In order to determine whether the number of shares of Common Stock to be delivered to a Holder upon the conversion of such Holder’s shares of Series A Preferred Stock will include a fractional share, such determination shall be based on the aggregate number of shares of Series A Preferred Stock of such Holder that are being converted on any single Conversion Date.

SECTION 12. Adjustment for Reorganization Events.

(a) Reorganization Events. In the event of:

(i) any reclassification, statutory exchange, merger, consolidation or other similar business combination of the Company with or into another Person, in each case, pursuant to which at least a majority of the Common Stock is changed or converted into, or exchanged for, cash, securities or other property of the Company or another Person;

(ii) any sale, transfer, lease or conveyance to another Person of all or a majority of the property and assets of the Company, in each case pursuant to which the Common Stock is converted into cash, securities or other property; or

(iii) any statutory exchange of securities of the Company with another Person (other than in connection with a merger or acquisition) or reclassification, recapitalization or reorganization of the Common Stock into other securities;

(each of which is referred to as a “Reorganization Event”), each share of Series A Preferred Stock outstanding immediately prior to such Reorganization Event will, without the consent of

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the Holders and subject to Section 12(d) and Section 13(b), remain outstanding but shall become convertible into, out of funds legally available therefor, the number, kind and amount of securities, cash and other property (the “Exchange Property”) (without any interest on such Exchange Property and without any right to dividends or distribution on such Exchange Property which have a record date that is prior to the applicable Conversion Date) that the Holder of such share of Series A Preferred Stock would have received in such Reorganization Event had such Holder converted its shares of Series A Preferred Stock into the applicable number of shares of Common Stock immediately prior to the effective date of the Reorganization Event using the Conversion Rate applicable immediately prior to the effective date of the Reorganization Event and the Accreted Value applicable at the time of such subsequent conversion; provided that the foregoing shall not apply if such Holder is a Person with which the Company consolidated or into which the Company merged or which merged into the Company or to which such sale or transfer was made, as the case may be (any such Person, a “Constituent Person”), or an Affiliate of a Constituent Person, to the extent such Reorganization Event provides for different treatment of Common Stock held by such Constituent Persons or such Affiliate thereof. If the kind or amount of securities, cash and other property receivable upon such Reorganization Event is not the same for each share of Common Stock held immediately prior to such Reorganization Event by a Person (other than a Constituent Person or an Affiliate thereof), then for the purpose of this Section 12(a), the kind and amount of securities, cash and other property receivable upon conversion following such Reorganization Event will be deemed to be the weighted average of the types and amounts of consideration received by the holders of Common Stock.

(b) Successive Reorganization Events. The above provisions of this Section 12 shall similarly apply to successive Reorganization Events and the provisions of Section 11 shall apply to any shares of Capital Stock received by the holders of the Common Stock in any such Reorganization Event.

(c) Reorganization Event Notice. The Company (or any successor) shall, no less than thirty (30) days prior to the anticipated effective date of any Reorganization Event, provide written notice to the Holders of such occurrence of such event and of the kind and amount of the cash, securities or other property that constitutes the Exchange Property. Failure to deliver such notice shall not affect the operation of this Section 12.

(d) Reorganization Event Agreements. The Company shall not enter into any agreement for a transaction constituting a Reorganization Event unless (i) such agreement provides for or does not interfere with or prevent (as applicable) conversion of the Series A Preferred Stock into the Exchange Property in a manner that is consistent with and gives effect to this Section 12, and (ii) to the extent that the Company is not the surviving corporation in such Reorganization Event or will be dissolved in connection with such Reorganization Event, proper provision shall be made in the agreements governing such Reorganization Event for the conversion of the Series A Preferred Stock into stock of the Person surviving such Reorganization Event or such other continuing entity in such Reorganization Event.

SECTION 13. Voting Rights.

(a) General. Except as provided in Section 13(b) and Section 14, Holders of shares of Series A Preferred Stock shall be entitled to vote as a single class with the holders of

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the Common Stock and the holders of any other class or series of Capital Stock of the Company then entitled to vote with the Common Stock on all matters submitted to a vote of the holders of Common Stock (and, if applicable, holders of any other class or series of Capital Stock of the Company). Each Holder shall be entitled to the number of votes equal to the product of (i) the largest number of whole shares of Common Stock into which all shares of Series A Preferred Stock could be converted pursuant to Section 6 (taking into account the Conversion Restriction to the extent applicable) multiplied by (ii) a fraction the numerator of which is the number of shares of Series A Preferred Stock held by such Holder and the denominator of which is the aggregate number of issued and outstanding shares of Series A Preferred Stock, in each case at and calculated as of the record date for the determination of stockholders entitled to vote or consent on such matters or, if no such record date is established, at and as of the date such vote or consent is taken or any written consent of stockholders is first executed. The Holders shall be entitled to notice of any meeting of holders of Common Stock in accordance with the Articles of Incorporation and Bylaws of the Company.

(b) Consent Rights. The vote or consent of the Holders of at least a majority of the shares of Series A Preferred Stock outstanding at such time, voting together as a separate class, given in person or by proxy, either in writing without a meeting or by vote at any meeting called for the purpose, will be necessary for effecting or validating any of the following actions, whether or not such approval is required pursuant to the Texas Business Organizations Code:

(i) any amendment, alteration or repeal (whether by merger, consolidation or otherwise) of any provision of the Articles of Incorporation (including this Certificate of Designations) or Bylaws that would have an adverse effect on the rights, preferences, privileges or voting power of the Series A Preferred Stock or the Holder thereof;

(ii) any amendment or alteration (whether by merger, consolidation or otherwise) of, or any supplement (whether by a certificate of designations or otherwise) to, the Articles of Incorporation or any provision thereof, or any other action to authorize or create, or increase the number of authorized or issued shares of, or any securities convertible into shares of, or reclassify any security into, or issue, any Parity Stock or Senior Stock or any other class or series of Capital Stock of the Company ranking senior to, or on a parity basis with, the Series A Preferred Stock as to dividend rights or rights on the distribution of assets on any voluntary or involuntary liquidation, dissolution or winding up of the affairs of the Company;

(iii) any issuance of shares of Series A Preferred Stock after the Original Issuance Date other than in connection with the conversion of Series B Preferred Stock that was issued on the Original Issuance Date;

(iv) any action that would cause the Company to cease to be treated as a domestic C corporation for U.S. federal income tax purposes;

(v) on or prior to the Business Day immediately following the Stockholder Meeting, effect any action that would result in (A) a change to the Conversion Rate, (B) the obligation to pay Participating Dividends or (C) the payment of cash dividends in respect of the Series B Preferred Stock; and

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(vi) any incurrence of any Indebtedness of the Company or any of its Subsidiaries (other than (x) the refinancing of any existing Indebtedness in an aggregate principal amount that does not exceed the then outstanding principal amount of the Indebtedness refinanced, plus all unpaid accrued or capitalized interest thereon, any prepayment premium applicable thereto, any swap breakage costs or hedge termination costs related thereto, upfront fees and original issue discount on such refinancing indebtedness, and customary fees and expenses relating to such financing, and (y) ordinary course of business working capital draws under the Company’s revolving credit facility) to the extent that, immediately after giving effect to such incurrence or refinancing, the ratio of the consolidated Indebtedness of the Company and its Subsidiaries (net of unrestricted cash and cash equivalents of the Company and its Subsidiaries) to the EBITDA of the Company and its Subsidiaries for the most recently ended four fiscal quarters for which internal financial statements are available immediately preceding the date on which such additional Indebtedness is incurred would not be less than a ratio of 5.15-to-1 on a pro forma basis after giving effect to such incurrence and the use of the proceeds therefrom;

provided, however, (A) that, with respect to the occurrence of any of the events set forth in clause (i) above, so long as (1) the Series A Preferred Stock remains outstanding with the terms thereof materially unchanged, or (2) the holders of the Series A Preferred Stock receive equity securities with rights, preferences, privileges and voting power substantially the same as those of the Series A Preferred Stock, then the occurrence of such event shall not be deemed to adversely affect such rights, preferences, privileges or voting power of the Series A Preferred Stock, and in such case such holders shall not have any voting rights with respect to the occurrence of any of the events set forth in clause (i) above and (B) that the authorization or creation of, or the increase in the number of authorized or issued shares of, or any securities convertible into shares of, or the reclassification of any security (other than the Series A Preferred Stock) into, or the issuance of, Junior Stock will not require the vote the holders of the Series A Preferred Stock.

For purposes of this Section 13, the filing in accordance with applicable law of a certificate of designations or any similar document setting forth or changing the designations, powers, preferences, rights, qualifications, limitations and restrictions of any class or series of stock of the Company shall be deemed an amendment to the Articles of Incorporation.

(c) Each Holder of Series A Preferred Stock will have one vote per share of Series A Preferred Stock on any matter on which Holders of Series A Preferred Stock are entitled to vote separately as a class, whether at a meeting or by written consent.

(d) The vote or consent of the Holders of a majority of the shares of Series A Preferred Stock outstanding at such time, voting together as a single class, given in person or by proxy, either in writing without a meeting or by vote at any meeting called for the purpose, will be sufficient to waive or amend the provisions of Section 9(e) of this Certificate of Designations, and any amendment or waiver of any of the provisions of Section 9(e) approved by such percentage of the Holders shall be binding on all of the Holders.

(e) For the avoidance of doubt and notwithstanding anything to the contrary in the Articles of Incorporation or Bylaws of the Company, the Holders of Series A Preferred Stock shall have the exclusive consent and voting rights set forth in Sections 13(b) and 14 and may

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take action or consent to any action with respect to such rights without a meeting by delivering a consent in writing or by electronic transmission of the Holders of the Series A Preferred Stock entitled to cast not less than the minimum number of votes that would be necessary to authorize, take or consent to such action at a meeting of stockholders.

SECTION 14. Election of Directors. Provided that the Fall Away of Investor Board Rights has not occurred and subject to Section 5.10(b) of the Investment Agreement, (i) the Holders of a majority of the then outstanding shares of Series A Preferred Stock shall have, at each annual meeting of the Company’s stockholders at which the Board is obligated to nominate one or more Investor Designees for election to the Board pursuant to and in accordance with the Investment Agreement, the exclusive right, voting separately as a class, to elect or appoint such Investor Designee(s) to the Board, irrespective of whether the Board has nominated such Investor Designee(s), (ii) notwithstanding anything to the contrary in the Articles of Incorporation or Bylaws, the Holders of a majority of the then outstanding shares of Series A Preferred Stock shall have the exclusive right to remove any Investor Designee(s) at any time for any reason or no reason (with or without cause) by sending a written notice to the Company and, upon receipt of such notice by the Company, such Investor Designee(s) shall be deemed to have resigned from the Board, and (iii) in the event of the death, disability, resignation or removal of any Investor Designee(s), the Investor Parties shall have the exclusive right to designate or appoint a successor to fill the vacancy created thereby. The Board and the holders of Common Stock shall not have the right to remove any Investor Designee from the Board (even for cause), such right of removal being vested exclusively with the Holders of a majority of the then outstanding shares of Series A Preferred Stock.

SECTION 15. Preemptive Rights. Except for the right to participate in any issuance of new equity securities by the Company, as set forth in the Investment Agreement, the Holders shall not have any preemptive rights.

SECTION 16. Term. Except as expressly provided in this Certificate of Designations, the shares of Series A Preferred Stock shall not be redeemable or otherwise mature and the term of the Series A Preferred Stock shall be perpetual.

SECTION 17. Creation of Capital Stock. Subject to Section 13(b)(ii), the Board, or any duly authorized committee thereof, without the vote of the Holders, may authorize and issue additional shares of Capital Stock of the Company.

SECTION 18. No Sinking Fund. Shares of Series A Preferred Stock shall not be subject to or entitled to the operation of a retirement or sinking fund.

SECTION 19. Transfer Agent, Conversion Agent, Registrar and Paying Agent. The duly appointed Transfer Agent, Conversion Agent, Registrar and paying agent for the Series A Preferred Stock shall be Computershare Trust Company, N.A. The Company may, in its sole discretion, appoint any other Person to serve as Transfer Agent, Conversion Agent, Registrar or paying agent for the Series A Preferred Stock and thereafter may remove or replace such other Person at any time. Upon any such appointment or removal, the Company shall send notice thereof by first class mail, postage prepaid, to the Holders.

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SECTION 20. Replacement Certificates. (a) Mutilated, Destroyed, Stolen and Lost Certificates. If physical certificates evidencing the Series A Preferred Stock are issued, the Company shall replace any mutilated certificate at the Holder’s expense upon surrender of that certificate to the Transfer Agent. The Company shall replace certificates that become destroyed, stolen or lost at the Holder’s expense upon delivery to the Company and the Transfer Agent of satisfactory evidence that the certificate has been destroyed, stolen or lost, together with any indemnity that may be required by the Transfer Agent and the Company.

(b) Certificates Following Conversion. If physical certificates representing the Series A Preferred Stock are issued, the Company shall not be required to issue replacement certificates representing shares of Series A Preferred Stock on or after the Conversion Date applicable to such shares. In place of the delivery of a replacement certificate following the applicable Conversion Date, the Transfer Agent, upon receipt of the satisfactory evidence and indemnity described in clause (a) above, shall deliver the shares of Common Stock issuable upon conversion of such shares of Series A Preferred Stock formerly evidenced by the physical certificate.

SECTION 21. Taxes. (a) Transfer Taxes. The Company shall pay any and all stock transfer, documentary, stamp and similar taxes that may be payable in respect of any issuance or delivery of shares of Series A Preferred Stock or shares of Common Stock or other securities issued on account of Series A Preferred Stock pursuant hereto or certificates representing such shares or securities. However, in the case of conversion of Series A Preferred Stock, the Company shall not be required to pay any such tax that may be payable in respect of any transfer involved in the issuance or delivery of shares of Series A Preferred Stock, shares of Common Stock or other securities to a beneficial owner other than the beneficial owner of the Series A Preferred Stock immediately prior to such conversion, and shall not be required to make any such issuance, delivery or payment unless and until the Person otherwise entitled to such issuance, delivery or payment has paid to the Company the amount of any such tax or has established, to the satisfaction of the Company, that such tax has been paid or is not payable.

(b) Withholding. All payments and distributions (or deemed distributions) on the shares of Series A Preferred Stock (and on the shares of Common Stock received upon their conversion) shall be subject to withholding and backup withholding of taxes to the extent required by law, subject to applicable exemptions, and amounts withheld, if any, shall be treated as received by the Holders.

SECTION 22. Notices. All notices referred to herein shall be in writing and, unless otherwise specified herein, all notices hereunder shall be deemed to have been given (a) upon the earlier of receipt thereof or three (3) Business Days after the mailing thereof if sent by registered or certified mail with postage prepaid, or by private courier service addressed: (i) if to the Company, to its office at Zix Corporation, 2711 N. Haskell Avenue, Suite 2200, LB 36, Dallas, Texas 75204-2960 (Attention: General Counsel), (ii) if to any Holder, to such Holder at the address of such Holder as listed in the stock record books of the Company (which may include the records of the Transfer Agent) or (iii) to such other address as the Company or any such Holder, as the case may be, shall have designated by notice similarly given; or (b) on the date sent by facsimile or transmitted to an email address designated by the Company or any such Holder if sent during normal business hours, and on the next Business Day if sent after normal business hours of the recipient.

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SECTION 23. Facts Ascertainable. When the terms of this Certificate of Designations refers to a specific agreement or other document to determine the meaning or operation of a provision hereof, the Secretary of the Company shall maintain a copy of such agreement or document at the principal executive offices of the Company and a copy thereof shall be provided free of charge to any Holder who makes a request therefor. The Secretary of the Company shall also maintain a written record of the Issuance Date, the number of shares of Series A Preferred Stock issued to a Holder and the date of each such issuance, and shall furnish such written record free of charge to any Holder who makes a request therefor.

SECTION 24. Waiver. Notwithstanding any provision in this Certificate of Designations to the contrary, any provision contained herein and any right of the Holders of Series A Preferred Stock granted hereunder may be waived as to all shares of Series A Preferred Stock (and the Holders thereof) upon the vote or written consent of the Holders of a majority of the shares of Series A Preferred Stock then outstanding.

SECTION 25. Severability. If any term of the Series A Preferred Stock set forth herein is invalid, unlawful or incapable of being enforced by reason of any rule of law or public policy, all other terms set forth herein which can be given effect without the invalid, unlawful or unenforceable term will, nevertheless, remain in full force and effect, and no term herein set forth will be deemed dependent upon any other such term unless so expressed herein.

SECTION 26. Business Opportunities. To the fullest extent permitted by Section 2.101(21) of the Texas Business Organizations Code (or any successor provision) and except as may be otherwise expressly agreed in writing by the Company and the Investor Parties, the Company, on behalf of itself and its Subsidiaries, renounces any interest or expectancy of the Company and its Subsidiaries in, or in being offered an opportunity to participate in, business opportunities, that are from time to time presented to the Investor Parties or any of their respective officers, representatives, directors, agents, stockholders, members, partners, Affiliates, Subsidiaries (other than the Company and its Subsidiaries), or any of their respective designees on the Company’s Board and/or any of their respective representatives who, from time to time, may act as officers of the Company, even if the opportunity is one that the Company or its Subsidiaries might reasonably be deemed to have pursued or had the ability or desire to pursue if granted the opportunity to do so, and no such person shall be liable to the Company or any of its Subsidiaries for breach of any fiduciary or other duty, as a director or officer or otherwise, by reason of the fact that such person pursues or acquires such business opportunity, directs such business opportunity to another person or fails to present such business opportunity, or information regarding such business opportunity, to the Company or its Subsidiaries unless, in the case of any such person who is a director or officer of the Company, such business opportunity is expressly offered to such director or officer in writing solely in his or her capacity as a director or officer of the Company. Any Person purchasing or otherwise acquiring any interest in any shares of Capital Stock of the Company shall be deemed to have notice of and consented to the provisions of this Section 26. Neither the alteration, amendment or repeal of this Section 26, nor the adoption of any provision of the Articles of Incorporation or this Certificate of Designations inconsistent with this Section 26, nor, to the fullest extent permitted by Texas

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law, any modification of law, shall eliminate or reduce the effect of this Section 26 in respect of any business opportunity first identified or any other matter occurring, or any cause of action, suit or claim that, but for this Section 26, would accrue or arise, prior to such alteration, amendment, repeal, adoption or modification. If any provision or provisions of this Section 26 shall be held to be invalid, illegal or unenforceable as applied to any circumstance for any reason whatsoever: (a) the validity, legality and enforceability of such provisions in any other circumstance and of the remaining provisions of this Section 26 (including, without limitation, each portion of any paragraph of this Section 26 containing any such provision held to be invalid, illegal or unenforceable that is not itself held to be invalid, illegal or unenforceable) shall not in any way be affected or impaired thereby and (b) to the fullest extent possible, the provisions of this Section 26 (including, without limitation, each such portion of any paragraph of this Section 26 containing any such provision held to be invalid, illegal or unenforceable) shall be construed so as to permit the Company to protect its directors, officers, employees and agents from personal liability in respect of their good faith service to or for the benefit of the Company to the fullest extent permitted by law. This Section 26 shall not limit any protections or defenses available to, or indemnification or advancement rights of, any director, officer, employee or agent of the Company under the Articles of Incorporation, the Bylaws, any other agreement between the Company and such director, officer, employee or agent or applicable law.

[Signature Page Follows]

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IN WITNESS WHEREOF, the Company has caused this Certificate of Designations to be executed this 15 day of February, 2019.

ZIX CORPORATION
By:	/s/ David Rockvam
Name:	David Rockvam
Title:	Vice President and Chief Financial Officer

[Signature Page to Series A Preferred Stock Certificate of Designations]