EcoR1 Capital, LLC

Holdings History for Zymeworks Inc. - Common Stock, $0.00001 par value per share (ZYME)

Symbol: ZYME on Nasdaq
Investment type: Equity / Common Stock, $0.00001 par value per share
Latest Disclosed Shares Owned: 22,970,388 shares
Security Ownership %: 31%

Shares, Excluding Options vs Price

Value, Excluding Options

EcoR1 Capital, LLC ownership in Zymeworks Inc. Common Stock, $0.00001 par value per share (ZYME)

19 Nov 2025 - EcoR1 Capital, LLC has filed an SCHEDULE 13D/A form with the Securities and Exchange Commission (SEC) disclosing ownership of 22,970,388 shares of Zymeworks Inc. Common Stock, $0.00001 par value per share (ZYME). This represents 31% ownership of the company. In their previous filing dated 27 Jun 2025, EcoR1 Capital, LLC had reported owning 22,970,388 shares, indicating a new holding.

Reporting Name	Ownership %	Change	Value $	Shares owned	Change	Activity %	Price	Form	Report date	Filing time
EcoR1 Capital, LLC	31%	0%	$420,817,508	22,970,388	0		$18.32	13D/A	16 Nov 2025	19 Nov 2025, 17:39
EcoR1 Capital, LLC	31%	+21%	$257,957,457	22,970,388	+5,270,614	+30%	$11.23	13D	26 Jun 2025	27 Jun 2025, 18:14
EcoR1 Capital, LLC	25%	+5%	$222,486,159	17,699,774	+841,356	+5%	$12.57	13D/A	04 Apr 2025	08 Apr 2025, 16:24
EcoR1 Capital, LLC	24%	+6.1%	$211,910,314	16,858,418	+1,138,257	+7.2%	$12.57	13D/A	13 Mar 2025	17 Mar 2025, 19:50
EcoR1 Capital, LLC	23%	+1.8%	$197,602,424	15,720,161	+309,083	+2%	$12.57	13D/A	17 Feb 2025	18 Feb 2025, 18:25
EcoR1 Capital, LLC	22%	+5.2%	$193,717,250	15,411,078	+718,797	+4.9%	$12.57	13D/A	10 Jan 2025	13 Jan 2025, 19:18
EcoR1 Capital, LLC	21%		$184,681,972	14,692,281			$12.57	13D/A	19 Dec 2024	23 Dec 2024, 19:54

Holdings date	Weight	Change	Value $	Shares	Change	Activity %	Price	All Holders
31 Dec 2025	28%	0%	$604,810,316	22,970,388	0		$26.33	Q4 2025
30 Sep 2025	19%	0%	$392,334,227	22,970,388	0		$17.08	Q3 2025
30 Jun 2025	17%	+4.3%	$288,278,369	22,970,388	+5,710,840	+33%	$12.55	Q2 2025
31 Mar 2025	12%	+1.6%	$205,561,217	17,259,548	+2,231,469		$11.91	Q1 2025
31 Dec 2024	8.8%	+0.93%	$220,011,077	15,028,079	+1,590,606	+12%	$14.64	Q4 2024
30 Sep 2024	5.8%	0%	$168,640,286	13,437,473	0		$12.55	Q3 2024
30 Jun 2024	3.5%	0%	$114,352,895	13,437,473	0		$8.51	Q2 2024
31 Mar 2024	3.6%	0%	$141,362,216	13,437,473	0		$10.52	Q1 2024
31 Dec 2023	3.6%	0%	$139,615,344	13,437,473	0		$10.39	Q4 2023
30 Sep 2023	2.9%	0%	$85,193,579	13,437,473	0		$6.34	Q3 2023
30 Jun 2023	3.1%	+0.76%	$116,099,767	13,437,473	+3,350,000	+33%	$8.64	Q2 2023
31 Mar 2023	2.9%	+0.73%	$91,190,756	10,087,473	+2,518,900	+33%	$9.04	Q1 2023
31 Dec 2022	1.8%	+1.8%	$59,488,984	7,568,573	+7,568,573	NEW	$7.86	Q4 2022

* Reported Price is the price of the security as of the portfolio date. This value is significant in that it is the last known price at which the security was still held.
An asterisk sign (*) next to the price indicates that the price is likely invalid.