Michele M. Leonhart - Jun 25, 2025 Form 4 Insider Report for 908 Devices Inc. (MASS)

Role: Director
Signature: /s/ Michael S. Turner, as Attorney-in-Fact
Stock symbol: MASS
Transactions as of: Jun 25, 2025
Transactions value $: $0
Form type: 4
Date filed: 6/27/2025, 04:01 PM
Previous filing: Jun 13, 2025
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Leonhart Michele M.	Director	C/O 908 DEVICES INC., 645 SUMMER STREET, BOSTON	/s/ Michael S. Turner, as Attorney-in-Fact	2025-06-27	0002027457

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	MASS	Common Stock	Options Exercise		+6.49K			6.49K	Jun 25, 2025	Direct	F1

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	MASS	Restricted Stock Units	Options Exercise	$0	-6.49K	-33.33%	$0.00	13K	Jun 25, 2025	Common Stock	6.49K		Direct	F1, F2

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	Each Restricted Stock Unit ("RSU") represents a contingent right to receive one share of Common Stock, par value $0.001, when vested. This transaction represents the settlement of RSUs in shares of Common Stock on their scheduled vesting date.
F2	The RSUs become vested in substantially equal annual installments over the 3 years following June 25, 2024, subject to the reporting person's continued service through the applicable vesting date, provided that, if the reporting person terminates their service for any reason, then a prorated number of RSUs will vest. The RSUs have no expiration date.