144 0001938192 XXXXXXXX LIVE 0001937653 Zymeworks Inc. 001-41535 108 Patriot Drive Suite A Middletown DE 19709 302-274-8744 Paul Andrew Moore Officer Common Stock Morgan Stanley Wealth Management Canada

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

9560 221505.20 74836534 01/12/2026 Nasdaq Common Stock 01/12/2026 Vesting of Restricted Stock Units Issuer N 17666 01/12/2026 Vesting of Award N Paul Andrew Moore

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

Common Stock 01/05/2026 20110 504698.65 The shares of common stock to be sold represent shares to be sold to cover tax withholding obligations and other fees in connection with the vesting of RSUs pursuant to mandatory "sell to cover" provisions contained in the applicable RSU grant agreement. 01/12/2026 /s/ Paul Andrew Moore