Zymeworks Inc. — Director's Dealing 2025

Apr 8, 2025

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: Zymeworks Inc. (ZYME)
CIK: 0001937653
Period of Report: 2025-04-03

Reporting Person: EcoR1 Capital, LLC (Director, 10% Owner)
Reporting Person: NODELMAN OLEG (Director, 10% Owner)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2025-04-03	Common Stock	P	120770	$11.8421	Acquired	17503336	Indirect
2025-04-04	Common Stock	P	196438	$11.1679	Acquired	17699774	Indirect

Footnotes

F1: The reporting persons are EcoR1 Capital, LLC ("EcoR1"), Oleg Nodelman and EcoR1 Capital Fund Qualified, L.P. ("Qualified Fund"). EcoR1 is the general partner and investment adviser of private funds, including Qualified Fund (the "Funds"). Mr. Nodelman is the manager and controlling owner of EcoR1. EcoR1 is filing this Form 4 for itself and Qualified Fund. The filers are filing this Form 4 jointly, but not as a group, and each expressly disclaims membership in a group within the meaning of Rule 13d-5(b) under the Securities Exchange Act of 1934. The Funds hold these securities directly for the benefit of their investors. EcoR1 may be deemed to indirectly beneficially own them as the investment adviser to the Funds. Mr. Nodelman may be deemed to indirectly beneficially own them as the control person of EcoR1. The filers disclaim beneficial ownership of the securities except to the extent of their respective pecuniary interests therein.

F2: Qualified Fund purchased 113,233 of the shares purchased in this transaction.

F3: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $11.8101 to $11.9123 inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each seperate price within the ranges set forth in this footnote and footnote 6.

F4: After this transaction, Qualified Fund held 16,407,320 shares of the Issuer's Common Stock.

F5: Qualified Fund purchased 184,181 of the shares purchased in this transaction.

F6: The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $10.9804 to $11.2921, inclusive.

F7: After this transaction, Qualified Fund held 16,591,501 shares of the Issuer's Common Stock.