EcoR1 Capital, LLC

13F Holdings History for Zymeworks Inc. - Common Stock (ZYME)

Symbol: ZYME on Nasdaq
Investment type: Equity / Common Stock
Latest Disclosed Ownership: 23M shares
Security Ownership: 30.7%

Shares, Excluding Options vs Price

Value, Excluding Options

EcoR1 Capital, LLC ownership in Zymeworks Inc. Common Stock (ZYME)

2025-11-19 - EcoR1 Capital, LLC has filed an SCHEDULE 13D/A form with the Securities and Exchange Commission (SEC) disclosing ownership of 23M shares of Zymeworks Inc. Common Stock (ZYME). This represents 30.7% percent ownership of the company.

Reporting Name	Ownership %	Change	Value $	Shares owned	Change	Activity %	Price	Form	Report date	Filed at
EcoR1 Capital, LLC	30.7%		$421M	23M			$18.32	13D/A	11/16/2025	19 Nov 2025 17:39:39
EcoR1 Capital, LLC	30.7%	+21.2%	$260M	23M	+5,270,614	+29.8%	$11.31	13D	6/26/2025	27 Jun 2025 18:14:18
EcoR1 Capital, LLC	25.4%	+5%	$211M	17.7M	+841,356	+4.99%	$11.92	13D/A	4/4/2025	8 Apr 2025 16:24:32
EcoR1 Capital, LLC	24.2%	+6.09%	$201M	16.9M	+1,138,257	+7.24%	$11.92	13D/A	3/13/2025	17 Mar 2025 19:50:35
EcoR1 Capital, LLC	22.8%	+1.82%	$187M	15.7M	+309,083	+2.01%	$11.92	13D/A	2/17/2025	18 Feb 2025 18:25:18
EcoR1 Capital, LLC	22.4%	+5.24%	$184M	15.4M	+718,797	+4.89%	$11.92	13D/A	1/10/2025	13 Jan 2025 19:18:17
EcoR1 Capital, LLC	21.3%		$175M	14.7M			$11.92	13D/A	12/19/2024	23 Dec 2024 19:54:23

Holdings date	Weight	Change	Value $	Shares	Change	Activity %	Price	All Holders
9/30/2025	18.8%		$392M	23M			$17.08	Q3 2025
6/30/2025	17.1%	+4.25%	$288M	23M	+5,710,840	+33.1%	$12.55	Q2 2025
3/31/2025	12.2%	+1.58%	$206M	17.3M	+2,231,469		$11.91	Q1 2025
12/31/2024	8.81%	+0.93%	$220M	15M	+1,590,606	+11.8%	$14.64	Q4 2024
9/30/2024	5.78%		$169M	13.4M			$12.55	Q3 2024
6/30/2024	3.5%		$114M	13.4M			$8.51	Q2 2024
3/31/2024	3.59%		$141M	13.4M			$10.52	Q1 2024
12/31/2023	3.62%		$140M	13.4M			$10.39	Q4 2023
9/30/2023	2.87%		$85.2M	13.4M			$6.34	Q3 2023
6/30/2023	2.84%	+0.71%	$116M	13.4M	+3,350,000	+33.2%	$8.64	Q2 2023
3/31/2023	2.94%	+0.73%	$91.2M	10.1M	+2,518,900	+33.3%	$9.04	Q1 2023
12/31/2022	1.81%	+1.81%	$59.5M	7.57M	+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.