X0306 4 2022-06-15 true 0001555279 908 Devices Inc. MASS 0001283576 BARTHELEMY NICOLAS C/O 908 DEVICES INC. 645 SUMMER STREET BOSTON MA 02210 true false false false Common Stock, par value $0.001 2022-06-15 4 M false 1379.00 A 15379.00 D Common Stock, par value $0.001 13541.00 I See Footnote Restricted Stock Unit 2022-06-15 4 M false 1379.00 0.00 D Common Stock, par value $0.001 1379.00 0.00 D Each Restricted Stock Unit ("RSU") represents a contingent right to receive one share of Common Stock, par value $0.001, when vested. These securities are owned directly by The Barthelemy 2001 Trust. The reporting person and his spouse are trustees of The Barthelemy 2001 Trust and have joint voting and dispositive control with respect to all securities held by The Barthelemy 2001 Trust and may be deemed to be the beneficial owner of the securities held by The Barthelemy 2001 Trust. The RSUs became fully vested on June 15, 2022, the day prior to the 2022 Annual Meeting of the Stockholders of 908 Devices Inc. The RSUs have no expiration date. /s/ Michael S. Turner, as Attorney-in-Fact 2022-06-17