X0202 SCHEDULE 13G 0001325447 XXXXXXXX LIVE Common 06/30/2026 0001503274 Quanterix Corp 74766Q101 900 MIDDLESEX TURNPIKE BILLERICA MA 01821 Rule 13d-1(b) First Eagle Investment Management, LLC DE 2753165.00 0 2753165.00 0 2753165.00 5.8 IA FIRST EAGLE SMALL CAP OPPORTUNITY FUND DE 2421533.00 0 2421533.00 0 2421533.00 5.1 IC Quanterix Corp 900 MIDDLESEX TURNPIKE, BILLERICA, MA, 01821 First Eagle Investment Management, LLC, FIRST EAGLE SMALL CAP OPPORTUNITY FUND 1345 Avenue of the Americas, New York, NY 10105, United States DELAWARE N IA 2,753,165 5.8 2,753,165 0 2,753,165 0 Y N N First Eagle Investment Management, LLC (FEIM), an investment adviser registered under Section 203 of the Investment Advisers Act of 1940, is deemed to be the beneficial owner of 2,753,165 shares, or 5.84% of the common stock believed to be outstanding as a result of acting as investment adviser to various clients. Clients of FEIM have the right to receive and the ultimate power to direct the receipt of dividends from, or the proceeds of the sale of, such securities. The First Eagle Small Cap Opportunity Fund, a registered investment company for which FEIM acts as investment adviser, may be deemed to beneficially own 2,421,533 of these 2,753,165 shares, or 5.14% of the Company's Common Stock. Y Y Y N By signing below I certify that, to the best of my knowledge and belief, 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. First Eagle Investment Management, LLC David O'Connor 08/06/2026 FIRST EAGLE SMALL CAP OPPORTUNITY FUND David O'Connor 08/06/2026