X0206 3 2017-12-06 0 0001503274 Quanterix Corp QTRX 0001263377 BAL BRUCE J C/O QUANTERIX CORPORATION, 113 HARTWELL AVENUE LEXINGTON MA 02421 0 1 0 0 VP of Ops, Service and Quality Stock Option (right to buy) 5.08 2026-06-24 Common Stock 101120 D The option vested as to 25% of the shares on May 9, 2017 and vests as to an additional 2.083% of the shares per month thereafter until April 30, 2020. Reflects the 1-for-3.214 reverse stock split of the Issuer's common stock effected on December 4, 2017 in connection with the Issuer's initial public offering, pursuant to which (i) the number of shares of common stock underlying the option was divided by 3.214 and (ii) the exercise price of the option was multiplied by 3.214. Exhibit 24.1 - Power of Attorney /s/ Brian Keane, Attorney-in-fact 2017-12-06