Quanterix CORP Schedule 13G passive stakes

Portolan Capital Management, LLC and George McCabe have reported a change in their beneficial ownership of Quanterix Corp. common stock, now holding 4.02%.

First Eagle Investment Management, LLC and its affiliated fund report a combined beneficial ownership of 5.8% in Quanterix Corp. as of June 30, 2026.

Portolan Capital Management, LLC and George McCabe have filed a Schedule 13G reporting a 6.25% beneficial ownership stake in Quanterix Corp.

Ameriprise Financial, Inc. has filed a Schedule 13G, reporting beneficial ownership of 7.5% of Quanterix Corp. common stock as of March 31, 2026.

Ameriprise Financial, Inc. has filed a Schedule 13G, reporting beneficial ownership of 990,224 shares of Quanterix Corp. common stock, representing 2.1% of the class.

The Vanguard Group has reported zero beneficial ownership in Quanterix Corp common stock following an internal realignment.

Ameriprise Financial, Inc. and its subsidiaries have reported a beneficial ownership of 10.7% in Quanterix Corp. common stock as of December 31, 2025.

Telegraph Hill Partners and its affiliates have reported a 5.4% beneficial ownership stake in Quanterix Corp, totaling 2,504,648 shares of common stock.

Ameriprise Financial, Inc. and its subsidiaries have reported a beneficial ownership of 9.1% of Quanterix Corp.'s common stock, totaling 4,243,512 shares.

Portolan Capital Management, LLC and George McCabe report beneficial ownership of 9.36% of Quanterix Corp's common stock.

BlackRock, Inc. has filed an amendment to its Schedule 13G, revealing a 7.3% beneficial ownership stake in Quanterix Corp's common stock as of June 30, 2025.

Ameriprise Financial, Inc. and its affiliated entities have reported a collective beneficial ownership of 9.6% in Quanterix Corp's common stock as of March 31, 2025.

Portolan Capital Management, LLC and its manager George McCabe have reported a beneficial ownership of 7.64% of Quanterix Corp's common stock as of March 31, 2025, held for investment purposes.

AllianceBernstein L.P. has filed an amended Schedule 13G, confirming a passive beneficial ownership of 0.1% in Quanterix Corp's common stock as of March 31, 2025.

Ameriprise Financial, Inc. and its affiliated entities have filed an amended Schedule 13G, disclosing a combined beneficial ownership of 10.7% of Quanterix Corp's common stock as of April 30, 2025.

The Vanguard Group has filed an amended Schedule 13G, revealing a 6.51% beneficial ownership stake in Quanterix Corp as of March 31, 2025.

Millennium Management LLC and affiliated entities have filed an amended Schedule 13G for Quanterix Corporation, reporting a reduced beneficial ownership of 0.1% of common stock, with Integrated Core Strategies (US) LLC no longer holding shares.

Ameriprise Financial, Inc. and its affiliated entities, including Threadneedle Asset Management, have reported beneficial ownership of 8.3% of Quanterix Corp's common stock as of December 31, 2024, held for investment purposes.

AllianceBernstein L.P. has filed an amended Schedule 13G, reporting a 6.3% beneficial ownership stake in Quanterix Corp's common stock as of December 31, 2024.