X0306 4 2022-03-10 0 0001403752 Zymeworks Inc. ZYME 0001761857 Klompas Neil A C/O ZYMEWORKS INC. 114 EAST 4TH AVENUE, SUITE 800 VANCOUVER A1 V5T 1G4 BRITISH COLUMBIA, CANADA 0 1 0 0 Chief Operating Officer Common Shares 2022-03-10 4 M 0 2500 0.00 A 13547 D Common Shares 2022-03-10 4 M 0 2708 0.00 A 16255 D Common Shares 2022-03-10 4 S 0 2979 6.88 D 13276 D Common Shares 700 I Held by spouse Restricted Stock Unit 2022-03-10 4 M 0 2500 0.00 D Common Shares 2500 2500 D Restricted Stock Unit 2022-03-10 4 M 0 2708 0.00 D Common Shares 2708 5417 D Stock Option (Right to Buy) 7.00 2022-03-10 4 A 0 200000 0.00 A 2032-03-09 Common Shares 200000 200000 D Represents common shares issued upon vesting of one third of the restricted stock units ("RSUs") granted on March 10, 2020. Represents common shares issued upon vesting of one third of the RSUs granted on March 10, 2021. Represents common shares sold to cover tax withholding obligations and other applicable fees in connection with the vesting of RSUs. Pursuant to the terms of the applicable RSU grant agreement (each, a "Grant Agreement"), effective on the grant date of the RSUs, the Reporting Person adopted a 10b5-1 plan pursuant to which the Reporting Person elected to sell shares to cover tax withholding obligations and other applicable fees in accordance with the terms of the Grant Agreement. The Reporting Person is subject to a Lock Up Agreement that expires on March 27, 2022. The sale of shares is a permissible exemption under the terms of the Lock Up Agreement. The remaining shares held by the Reporting Person following this sale remain subject to the terms of the Lock Up Agreement. The price reported in Column 4 is a weighted average price. The shares were sold in multiple transactions at prices ranging from $6.83 to $6.97, inclusive. Upon request by the Commission staff, the Issuer, or a security holder of the Issuer, the Reporting Person will provide full information regarding the number of shares sold at each separate price. Each RSU represents the contingent right to receive, upon vesting of the RSU, one share of the Issuer's common stock. The RSUs were granted on March 10, 2020 and vest in three equal annual instalments beginning on March 10, 2021. The RSUs were granted on March 10, 2021 and vest in three equal annual instalments beginning on March 10, 2022. Stock options vest as follows: (i) 25% of underlying shares on first anniversary of grant date and (ii) remainder of underlying shares in 36 equal monthly installments on last day of month following first anniversary of grant date. /s/ Daniel Dex, Attorney-in-Fact 2022-03-11