144 0001604800 XXXXXXXX LIVE 0001937653 Zymeworks Inc. 001-41535 108 Patriot Drive, Suite A Middletown DE 19709 302-274-8744 Jeffrey T L Smith Former Officer Common Stock Morgan Stanley Wealth Management Canada

140 4th Ave. SW, Suite 2740 Calgary A0 T2P 3N3

247333 6133858.40 73749607 03/06/2026 Nasdaq Common Stock 03/06/2026 Exercise of Options Issuer N 220625 03/06/2026 Exercise and sell to cover Common Stock 01/12/2026 Vesting of Restricted Stock Units Issuer N 8356 01/12/2026 Compensation Common Stock 01/05/2026 Vesting of Restricted Stock Units Issuer N 9462 01/05/2026 Compensation Common Stock 01/05/2025 Vesting of Restricted Stock Units Issuer N 8890 01/05/2025 Compensation N Jeffrey T L Smith

c/o Zymeworks Inc. 108 Patriot Drive, Suite A Middletown, DE 19709

Common Stock 01/05/2026 10538 264471.13 Jeffrey T L Smith

c/o Zymeworks Inc. 108 Patriot Drive, Suite A Middletown, DE 19709

Common Stock 01/12/2026 9310 211090.28 03/06/2026 /s/ Jeffrey T L Smith