X0306 4/A 2018-02-26 2018-02-28 0 0000855612 ZIX CORP ZIXI 0001232607 BONNEY MARK J 2711 N. HASKELL AVENUE SUITE 2200 DALLAS TX 75204 1 0 0 0 Deferred Stock Units 2018-02-26 4 A 0 16337 0.00 A Common Stock 16337 95231 D Each deferred stock unit represents a contingent right to receive one share of ZIXI common stock. Grant under the Amended and Restated 2012 Incentive Plan (as amended, the "Plan"). The deferred stock units will vest pro-rata and quarterly over one year, and subject to acceleration under conditions described in the Plan. Delivery of the underlying shares in respect of vesting will occur pursuant to the underlying award agreement. This Form 4/A amends the Form 4 filed by the Reporting Person on February 28, 2018. The amount of securities directly beneficially owned by the Reporting Person has been historically reported incorrectly and should have been reported as 95,231 shares of common stock. /s/ Noah F. Webster, Attorney-in-Fact 2018-08-23