X0306 4 2021-12-23 1 0000855612 ZIX CORP ZIXI 0001742699 Webster Noah F 2711 N. HASKELL AVENUE SUITE 2300 DALLAS TX 75204 0 1 0 0 Chief Legal Officer Common Stock 2021-12-23 4 D 0 202988 8.50 D 0 D Restricted Stock Units 2021-12-23 4 D 0 36238 D Common Stock 36238 0 D On December 23, 2021, the Issuer was acquired by Open Text Corporation ("Parent") pursuant to the Agreement and Plan of Merger (the "Agreement"), dated as of November 7, 2021, by and among Parent, Issuer and Zeta Merger Sub Inc. (the "Merger"). At the effective time of the Merger (the "Effective Time"), each outstanding share of Issuer common stock (subject to limited exceptions) converted into the right to receive $8.50 in cash, without interest. Each restricted stock unit would convert into a share of common stock on a one-for-one basis. Pursuant to the Agreement and the letter agreement, dated December 18, 2021 between the Issuer and Parent (the "Letter Agreement"), each RSU outstanding as of immediately prior to the Effective Time was cancelled and converted into a right to receive an amount of cash equal to the Company Stock-Based Award Consideration (as defined in the Letter Agreement), payable in accordance with and subject to the terms of the Letter Agreement. Granted under the 2018 Omnibus Incentive Plan (the "Plan") consisting of restricted stock units that were schedule to vest pro-rata annually over 3 years, subject to acceleration under conditions described in the Plan. Includes shares granted under the Plan consisting of restricted stock. A portion of such shares would vest based on the Issuer's achievement of specific financial performance criteria and are subject to acceleration under conditions described in the Plan. /s/ Noah F. Webster 2021-12-28