SCHEDULE: Ameriprise Financial Discloses 9.1% Stake in Quanterix

Ameriprise Financial, Inc. and its subsidiaries have reported a combined beneficial ownership of 9.1% of Quanterix Corp.'s common stock as of September 30, 2025.

Summary

• Ameriprise Financial, Inc. and its affiliated entities collectively hold a significant stake in Quanterix Corp.
• Ameriprise Financial, Inc. beneficially owns 4,243,512 shares, representing 9.1% of Quanterix Corp.'s common stock.
• Several subsidiaries, including TAM UK International Holdings Limited, Threadneedle Holdings Limited, TAM UK Holdings Limited, Threadneedle Asset Management Holdings Limited, TC Financing Ltd, Threadneedle Asset Management Limited, and Threadneedle Investment Services Limited, each beneficially own 3,136,112 shares, equating to 6.7% of the class.
• The shares reported by Ameriprise Financial, Inc. include those held by its subsidiaries.
• The reporting persons certify that the securities were acquired and are held in the ordinary course of business and not for the purpose of changing or influencing control of Quanterix Corp., except for activities related to nominations under Rule 14a-11.

Sentiment

Score: 7

Explanation: The disclosure of a substantial beneficial ownership by a major financial institution like Ameriprise Financial, Inc. is generally viewed positively as it indicates institutional confidence in the company. The passive nature of the stake (not for control) suggests a long-term investment perspective.

Positives

• Significant institutional investment by Ameriprise Financial, Inc. and its subsidiaries, indicating confidence in Quanterix Corp.
• Ameriprise Financial, Inc. holds 9.1% of the common stock, representing a substantial passive stake.

Risks

• The reporting persons certify that the securities were not acquired or held for the purpose of changing or influencing control of Quanterix Corp., mitigating concerns about activist investor intervention, except for potential nomination activities under Rule 14a-11.

Future Outlook

NA

Management Comments

• The securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under §§ 240.14a-11.

Industry Context

NA

Stakeholder Impact

• Shareholders: The disclosure of a significant institutional investor holding a substantial stake may increase investor confidence and potentially attract further institutional interest, positively impacting share price stability and liquidity.

Key Dates

Recommendation

The filing indicates a significant, passive institutional stake by Ameriprise Financial, Inc. in Quanterix Corp. This suggests a vote of confidence from a major financial player, which is generally a positive signal. However, as a Schedule 13G, it does not provide operational or financial performance details of Quanterix Corp. that would warrant a 'buy' or 'sell' recommendation. The 'hold' recommendation reflects the positive signal of institutional interest without new fundamental information to change the investment thesis.

Keywords

Quanterix Corp, QTRX, Ameriprise Financial, Threadneedle, institutional ownership, Schedule 13G, beneficial ownership, common stock, investment, SEC filing