Zymeworks Form 4 Shows EcoR1 Adds 5M Shares via Warrant Exercise

Rhea-AI Filing Summary

EcoR1 Capital, LLC, together with its affiliated fund and managing member Oleg Nodelman, filed a Form 4 disclosing the cashless exercise of 5,086,521 pre-funded warrants in Zymeworks Inc. (ticker: ZYME) on 26 Jun 2025.

• The warrants carried a nominal exercise price of $0.0001 per share. To settle the aggregate exercise price, the reporting persons instructed the issuer to withhold 41 shares (valued at $12.71 each), issuing the remaining 5,086,480 new common shares.
• Following the transaction, EcoR1’s Qualified Fund owns 21,582,563 ZYME shares and the group reports total indirect beneficial ownership of 22,970,388 shares.
• The derivative position (pre-funded warrants) is now fully exhausted; the reporting persons hold 0 derivative securities post-transaction.
• EcoR1 and Mr. Nodelman are both classified as 10% owners and hold board seats, reinforcing their strategic involvement with the company.

The filing signals continued insider alignment through an increase in equity exposure; however, it also converts previously outstanding warrants into issued equity, modestly expanding the public float.

Positive

• Insider confidence: 10% owner EcoR1 converted 5.1 M warrants, increasing its direct equity exposure.
• Removal of derivative overhang: All pre-funded warrants are now exercised, simplifying capital structure.
• Enhanced alignment: Board-affiliated investor now holds 22.97 M common shares, strengthening governance accountability.

Negative

• Share count increase: Issuance of 5.09 M new shares marginally dilutes existing shareholders.
• No cash inflow: Nominal $0.0001 exercise price yields de-minimis capital to the company.

Insights

Financial Analyst

TL;DR: EcoR1 converted 5.1 M pre-funded warrants, boosting its common share stake to 23 M and eliminating warrant overhang.

The warrant exercise adds 5.1 M shares to the outstanding count at a de-minimis cost, indicating EcoR1’s ongoing commitment as a long-term holder. Because pre-funded warrants are typically included in diluted share calculations, the impact on fully-diluted EPS is likely limited. Nonetheless, the shift from derivative to common stock removes execution risk and signals insider confidence, which investors often interpret positively. The small share withholding (41 shares) to cover exercise costs is immaterial. Overall, this is a constructive insider transaction with negligible cash inflow to the company.

Corporate Governance Specialist

TL;DR: Director/10% owner deepens equity stake, reinforcing governance influence.

EcoR1 and Oleg Nodelman already hold board representation; converting the warrants increases their voting power by roughly 5 million shares, further entrenching their influence. Because the exercise price is negligible, there is no meaningful capital contribution to the issuer, but the move aligns board and shareholder interests by turning options into vested ownership. No new compensation or dilution beyond what was already disclosed under the warrant terms arises. Overall governance impact is positive due to stronger insider alignment, with limited negative effects apart from a minor uptick in issued share count.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

EcoR1 Capital, LLC

(Last) (First) (Middle)

357 TEHAMA STREET #3

(Street)

SAN FRANCISCO CA 94103

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Zymeworks Inc. [ ZYME ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
06/26/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

	Form filed by One Reporting Person
X	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	06/26/2025		X		5,086,480(2)	A	$0.0001	22,970,388(3)	I	See Note(1)
Common Stock	06/26/2025		F(4)		41	D	$12.71	22,970,388(3)	I	See Note(1)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Pre-Funded Warrants (right to acquire)	$0.0001	06/26/2025		X			5,086,521(5)	12/26/2023	(6)	Common Stock	5,086,521	$0	0	I	See note(1)

1. Name and Address of Reporting Person^*

EcoR1 Capital, LLC

(Last) (First) (Middle)

357 TEHAMA STREET #3

(Street)

SAN FRANCISCO CA 94103

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

X	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

1. Name and Address of Reporting Person^*

NODELMAN OLEG

(Last) (First) (Middle)

357 TEHAMA STREET #3

(Street)

SAN FRANCISCO CA 94103

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

X	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

Explanation of Responses:

1. 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.

2. Qualified Fund acquired 4,818,424 shares of Common Stock in connection with the exercise of the pre-funded warrants.

3. After the transactions reported herein, Qualified Fund held 21,582,563 shares of the Issuer's Common Stock.

4. On June 26, 2025,the reporting persons exercised pre-funded warrants to purchase 5,086,521 shares of the Issuer's Common Stock for $0.0001 per share. The reporting persons paid the exercise price on a cashless basis, resulting in the Issuer withholding 41 of the warrant shares (including 38 warrant shares issuable to Qualified Fund) to pay the exercise price and issuing to the reporting persons the remaining 5,086,480 shares.

5. Qualified Fund exercised 4,818,462 of the pre-funded warrants reported in this transaction.

6. The pre-funded warrants did not have an expiration date.

Remarks:

Mr. Nodelman is a director of the Issuer. Scott Platshon, an employee of EcoR1, also serves as a director of the Issuer and was nominated for the board by EcoR1 and the Funds.

	/s/ Oleg Nodelman, Individually and as Manager of EcoR1 Capital, LLC	06/27/2025
	** Signature of Reporting Person	Date
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FAQ

How many ZYME shares did EcoR1 acquire on 26 Jun 2025?

EcoR1 received 5,086,480 additional common shares after netting 41 shares for the exercise price.

What is EcoR1’s total ownership in Zymeworks after the Form 4 transaction?

The group now reports indirect beneficial ownership of 22,970,388 common shares.

Were any derivative securities still outstanding after the warrant exercise?

No. The 5,086,521 pre-funded warrants were fully exercised, leaving 0 derivative securities.

Did Zymeworks receive significant cash from the warrant exercise?

No. The warrants had a $0.0001 per-share price, resulting in immaterial cash proceeds.

Does EcoR1 hold board representation at Zymeworks?

Yes. Oleg Nodelman and EcoR1 employee Scott Platshon serve as directors of the issuer.