Portolan Capital Management, LLC

13F Holdings History for Quanterix Corp - Common Stock, $0.001 par value per share (QTRX)

Symbol: QTRX on Nasdaq
Investment type: Equity / Common Stock, $0.001 par value per share
Latest Disclosed Ownership: 3.63M shares
Security Ownership: 9.36%

Shares, Excluding Options vs Price

Value, Excluding Options

Portolan Capital Management, LLC ownership in Quanterix Corp Common Stock, $0.001 par value per share (QTRX)

2025-08-13 - Portolan Capital Management, LLC has filed an SCHEDULE 13G/A form with the Securities and Exchange Commission (SEC) disclosing ownership of 3.63M shares of Quanterix Corp Common Stock, $0.001 par value per share (QTRX). This represents 9.36% percent ownership of the company. In their previous filing dated 2025-05-15, Portolan Capital Management, LLC had reported owning 2.96M shares, indicating an increase of 22.6% percent.

Reporting Name	Ownership %	Change	Value $	Shares owned	Change	Activity %	Price	Form	Report date	Filed at
Portolan Capital Management, LLC	9.36%	+21.5%	$16.5M	3.63M	+670,225	+22.6%	$4.54	13G/A	6/30/2025	13 Aug 2025 16:10:08
Portolan Capital Management, LLC	7.64%		$14.4M	2.96M			$4.86	13G/A	3/31/2025	15 May 2025 11:29:36

Holdings date	Weight	Change	Value $	Shares	Change	Activity %	Price	All Holders
6/30/2025	1.52%	+0.28%	$24.2M	3.63M	+670,225	+22.6%	$6.65	Q2 2025
3/31/2025	1.47%	+0.19%	$19.3M	2.96M	+375,573		$6.51	Q1 2025
12/31/2024	1.85%	+0.05%	$27.5M	2.59M	+67,138	+2.66%	$10.63	Q4 2024
9/30/2024	2.37%	+0.57%	$32.7M	2.52M	+602,656	+31.4%	$12.96	Q3 2024
6/30/2024	2.09%	+0.77%	$25.3M	1.92M	+755,201	+64.9%	$13.21	Q2 2024
3/31/2024	2.09%	-0.28%	$27.4M	1.16M	-134,261	-10.4%	$23.56	Q1 2024
12/31/2023	3.1%	-0.97%	$35.5M	1.3M	-378,748	-22.6%	$27.34	Q4 2023
9/30/2023	4.25%	+0.66%	$45.5M	1.68M	+259,215	+18.3%	$27.14	Q3 2023
6/30/2023	2.83%	+1.29%	$31.9M	1.42M	+646,884	+84%	$22.55	Q2 2023
3/31/2023	0.83%	-0.1%	$8.67M	770K	-92,486	-10.7%	$11.27	Q1 2023
12/31/2022	1.18%	+0.14%	$11.9M	862K	+103,372	+13.6%	$13.85	Q4 2022
9/30/2022	0.88%	+0.44%	$8.36M	759K	+376,978	+98.7%	$11.02	Q3 2022
6/30/2022	0.62%	+0.62%	$6.18M	382K	+381,875	NEW	$16.19	Q2 2022
3/31/2021		-0.16%	$0	0	-38,957	-100%		Q1 2021
12/31/2020	0.16%	-0.04%	$1.81M	39K	-8,943	-18.7%	$46.51	Q4 2020
9/30/2020	0.18%	-0.38%	$1.62M	47.9K	-100,819	-67.8%	$33.74	Q3 2020
6/30/2020	0.47%	-0.61%	$4.07M	149K	-196,281	-56.9%	$27.39	Q2 2020
3/31/2020	0.95%	-0.07%	$6.34M	345K	-26,337	-7.09%	$18.37	Q1 2020
12/31/2019	0.89%	+0.62%	$8.78M	371K	+261,086	+237%	$23.63	Q4 2019
9/30/2019	0.27%	+0.27%	$2.42M	110K	+110,251	NEW	$21.96	Q3 2019
12/31/2018		-0.48%	$0	0	-226,891	-100%		Q4 2018
9/30/2018	0.48%	+0.48%	$4.86M	227K	+226,891	NEW	$21.42	Q3 2018

* 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.