MASS 908 Devices Inc

FORM 4 [ ] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).         
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES                                                                                   
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Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940                       

1. Name and Address of Reporting Person * George Jeffrey P.	2. Issuer Name and Ticker or Trading Symbol 908 Devices Inc. [ MASS ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director                    _____ 10% Owner _____ Officer (give title below)    _____ Other (specify below)
(Last)          (First)          (Middle) C/O 908 DEVICES INC., 645 SUMMER STREET	3. Date of Earliest Transaction (MM/DD/YYYY) 6/17/2021
(Street) BOSTON, MA 02210 (City)        (State)        (Zip)	4. If Amendment, Date Original Filed (MM/DD/YYYY)	6. Individual or Joint/Group Filing (Check Applicable Line) _X _ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security (Instr. 3)	2. Trans. Date	2A. Deemed Execution Date, if any	3. Trans. Code (Instr. 8)		4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivate Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Trans. Date	3A. Deemed Execution Date, if any	4. Trans. Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Stock Option (option to buy)	$41.70	6/17/2021		A		2455		(1)	6/17/2031	Common Stock, par value $0.001	2455	$0.00	2455	D
Restricted Stock Unit	(2)	6/17/2021		A		1379		(3)	(3)	Common Stock, par value $0.001	1379	$0.00	1379	D

Explanation of Responses:
(1)	The shares underlying the option become vested and exercisable in substantially equal monthly installments over the 12 months following June 17, 2021, subject to the reporting person's continued service through the applicable vesting date.
(2)	Each Restricted Stock Unit ("RSU") represents a contingent right to receive one share of Common Stock, par value $0.001, when vested.
(3)	The RSUs become fully vested on June 17, 2022 or the 2022 Annual Meeting of the Stockholders of 908 Devices Inc., whichever occurs first, 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.

Reporting Owners
Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
George Jeffrey P. C/O 908 DEVICES INC. 645 SUMMER STREET BOSTON, MA 02210	X

Signatures
/s/ Michael S. Turner, as Attorney-in-Fact		6/21/2021
**Signature of Reporting Person		Date