Brandi C. Vann - 01 Aug 2025 Form 4 Insider Report for 908 Devices Inc. (MASS)

Role: Director
Signature: /s/ Michael S. Turner, as Attorney-in-Fact
Issuer symbol: MASS
Transactions as of: 01 Aug 2025
Net transactions value: $0
Form type: 4
Filing time: 18 Aug 2025, 16:03:16 UTC
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Vann Brandi C	Director	C/O 908 DEVICES INC., 44 THIRD AVENUE, BURLINGTON	/s/ Michael S. Turner, as Attorney-in-Fact	18 Aug 2025	0002081945

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 Unit	Award	$0	+15,577		$0.000000	15,577	01 Aug 2025	Common Stock	15,577		Direct	F1, F2, F3
transaction	MASS	Stock Option (option to buy)	Award	$0	+20,409		$0.000000	20,409	01 Aug 2025	Common Stock	20,409	$5.14	Direct	F2, F4

* 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.
F2	This Form 4 is being filed late due to an inadvertent administrative error.
F3	The RSUs become vested in substantially equal annual installments over the 3 years following August 1, 2025, 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.
F4	The shares underlying the option become vested and exercisable in substantially equal monthly installments over the 36 months following August 1, 2025, subject to the reporting person's continued service through the applicable vesting date.