X0306 4 2016-01-15 0001463172 Zendesk, Inc. ZEN 0001615739 Price Matthew Adrian 1019 MARKET STREET SAN FRANCISCO CA 94103 1 SVP Emerging Bus./Corp Mktg Common Stock 2016-01-15 4 M 0 144 A 2077 D Common Stock 2016-01-15 4 F 0 78 23.94 D 1999 D Restricted Stock Unit 2016-01-15 4 M 0 144 D 2022-02-04 Common Stock 144 5319 D Restricted stock units convert into common stock on a one-for-one basis. Represents the number of shares withheld by the Issuer in satisfaction of tax withholding obligations in connection with the vesting of the restricted stock units listed in Table II. Such withholding is mandated by an election of the Issuer made in advance and does not represent a discretionary trade by the reporting person. 1/48th of the shares issuable pursuant to the restricted stock unit shall vest monthly after the vesting commencement date of February 15, 2015, subject to the Reporting Person's continuous service to the Issuer on each such date. 100% of the then unvested shares are subject to acceleration upon the occurrence of certain events. /s/ John Geschke, Attorney-in-Fact for Matthew Adrian Price 2016-01-19