Joseph H. Griffith IV - 01 Feb 2026 Form 4 Insider Report for 908 Devices Inc. (MASS)

Role: Chief Financial Officer
Signature: /s/ Mark S. Levine, Attorney-in-Fact
Issuer symbol: MASS
Transactions as of: 01 Feb 2026
Net transactions value: -$143,222
Form type: 4
Filing time: 03 Feb 2026, 20:45:22 UTC
Previous filing: 06 Oct 2025
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Griffith Joseph H. IV	Chief Financial Officer	C/O 908 DEVICES INC., 44 3RD AVENUE, BURLINGTON	/s/ Mark S. Levine, Attorney-in-Fact	03 Feb 2026	0001431531

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	MASS	Common Stock	Options Exercise		+5,102	+5.5%		98,032	01 Feb 2026	Direct	F1
transaction	MASS	Common Stock	Options Exercise		+10,306	+11%		108,338	01 Feb 2026	Direct	F1
transaction	MASS	Common Stock	Options Exercise		+11,260	+10%		119,598	01 Feb 2026	Direct	F1
transaction	MASS	Common Stock	Options Exercise		+43,473	+36%		163,071	01 Feb 2026	Direct	F1
transaction	MASS	Common Stock	Sale	$143,222	-23,175	-14%	$6.18	139,896	02 Feb 2026	Direct	F2, F3

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	-5,102	-100%	$0.000000	0	01 Feb 2026	Common Stock	5,102		Direct	F1, F4
transaction	MASS	Restricted Stock Units	Options Exercise	$0	-10,306	-50%	$0.000000	10,306	01 Feb 2026	Common Stock	10,306		Direct	F1, F5
transaction	MASS	Restricted Stock Units	Options Exercise	$0	-11,260	-33%	$0.000000	22,521	01 Feb 2026	Common Stock	11,260		Direct	F1, F6
transaction	MASS	Restricted Stock Units	Options Exercise	$0	-43,473	-33%	$0.000000	86,945	01 Feb 2026	Common Stock	43,473		Direct	F1, F7
transaction	MASS	Restricted Stock Units	Award	$0	+121,164		$0.000000	121,164	02 Feb 2026	Common Stock	121,164		Direct	F1, F8
transaction	MASS	Stock Option (option to buy)	Award	$0	+52,967		$0.000000	52,967	02 Feb 2026	Common Stock	52,967	$6.19	Direct	F9

* 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, at settlement, one share of Common Stock. This transaction represents the settlement of RSUs in shares of Common Stock on their scheduled vesting date.
F2	The sale reported on this Form 4 represents shares sold by the Reporting Person to cover tax withholding obligations in connection with the vesting and settlement of RSUs. The sale is mandated by the Issuer's election to require the satisfaction of tax withholding obligations to be funded by a "sell to cover" transaction and does not represent a discretionary transaction by the Reporting Person.
F3	The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $6.105 to $6.35, inclusive. The reporting person undertakes to provide to Issuer, any security holder of Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote.
F4	These RSUs vest in four substantially equal annual installments at the four anniversary dates following February 1, 2022, subject to the reporting person's continued service through the applicable vesting date. The RSUs have no expiration date.
F5	These RSUs vest in four substantially equal annual installments at the four anniversary dates following February 1, 2023, subject to the reporting person's continued service through the applicable vesting date. The RSUs have no expiration date.
F6	These RSUs vest in four substantially equal annual installments at the four anniversary dates following February 1, 2024, subject to the reporting person's continued service through the applicable vesting date. The RSUs have no expiration date.
F7	The RSUs shall vest one-third on February 1, 2026, with the remaining two-thirds vesting in two substantially equal annual installments at the two anniversary dates following February 1, 2026, subject to the reporting person's continued service through the applicable vesting date. The RSUs have no expiration date.
F8	The RSUs shall vest one-third on February 1, 2027, with the remaining two-thirds vesting in two substantially equal annual installments at the two anniversary dates following February 1, 2027, subject to the reporting person's continued service through the applicable vesting date. The RSUs have no expiration date.
F9	One-third of the shares underlying the option become vested and exercisable on February 1, 2027, and the remaining two-thirds of the shares underlying the option become vested and exercisable in substantially equal monthly installments over the 24 months following February 1, 2027, subject to the reporting person's continued service through the applicable vesting date.