X0202 SCHEDULE 13G/A 0001104659-24-117757 0001687509 XXXXXXXX LIVE 2 Common Stock, $0.00001 par value per share 03/31/2026 0001937653 Zymeworks Inc. 98985Y108 108 Patriot Drive, Suite A Middletown DE 19709 Rule 13d-1(b) Rubric Capital Management LP DE 0.00 7000000.00 0.00 7000000.00 7000000.00 N 9.49 IA PN David Rosen X1 0.00 7000000.00 0.00 7000000.00 7000000.00 N 9.49 HC IN Zymeworks Inc. 108 Patriot Drive, Suite A Middletown, DE, 19709 This statement is filed by: (i) Rubric Capital Management LP ("Rubric Capital"), the investment adviser to certain investment funds and/or accounts (collectively, the "Rubric Funds") that hold the shares of Common Stock, $0.00001 par value (the "Common Stock") of Zymeworks Inc., a Delaware corporation (the "Issuer") reported herein; and (ii) David Rosen ("Mr. Rosen"), Managing Member of Rubric Capital Management GP LLC, the general partner of Rubric Capital. The foregoing persons are hereinafter sometimes collectively referred to as the "Reporting Persons." The filing of this statement should not be construed as an admission that any of the forgoing persons or any Reporting Person is, for the purposes of Section 13 of the Act, the beneficial owner of the shares of Common Stock reported herein. The address of the principal business office of each of the Reporting Persons is 155 East 44th St, Suite 1630, New York, NY 10017. Rubric Capital is a Delaware limited partnership. Mr. Rosen is a citizen of the United States of America. N IA HC The information required by Items 4(a) - (c) is set forth in Rows 9 of the cover page for each of the Reporting Persons and is incorporated herein by reference. The percentage set forth in Row (11) of the cover page for each of the Reporting Persons and in Item 4(b) is based on the 73,749,607 shares of Common Stock outstanding as of February 6, 2026, as reported in the Issuer's Quarterly Report on Form 10-K for the fiscal year ended December 31, 2026, filed with the Securities and Exchange Commission on March 2, 2026. 9.49 The information required by Item 4(c)(i) is set forth in Row 5 of the cover page for each of the Reporting Persons and is incorporated herein by reference. The information required by Item 4(c)(ii) is set forth in Row 6 of the cover page for each of the Reporting Persons and is incorporated herein by reference. The information required by Item 4(c)(iii) is set forth in Row 7 of the cover page for each of the Reporting Persons and is incorporated herein by reference. The information required by Item 4(c)(iv) is set forth in Row 8 of the cover page for each of the Reporting Persons and is incorporated herein by reference. Y N See Item 2(a). Rubric Capital Master Fund LP, a Rubric Fund, has the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, more than 5% of the Common Stock. Y Y Y N By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11. Rubric Capital Management LP /s/ Michael Nachmani 05/15/2026 David Rosen /s/ David Rosen 05/15/2026