X0206 3 2017-12-06 0 0001503274 Quanterix Corp QTRX 0001252546 HRUSOVSKY E KEVIN C/O QUANTERIX CORPORATION, 113 HARTWELL AVENUE LEXINGTON MA 02421 1 1 0 0 EC, President & CEO Common Stock 859972 D Stock Option (right to buy) 8.16 2027-03-31 Common Stock 311138 D 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. 139,022 shares are subject to time based vesting and 39,812 shares are subject to performance based vesting. The option vests as to 25% of the shares on March 31, 2018 and vests as to an additional 2.083% of the shares per month thereafter until February 28, 2021. 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