Christopher D. Brown

CIK: 0001836988

Transaction Breakdown

Open Market Buys (P)0 (0.0%)

High conviction signal

Open Market Sales (S)18 (69.2%)

Position reduction

Option Exercises (M)8 (30.8%)

Derivative conversions

Awards (A)0 (0.0%)

Compensation grants

Other (G, F, J, C, D, …)0 (0.0%)

Gifts, tax withholding, conversions, dispositions to the issuer and other codes

Companies & Roles (1)

MASS

908 Devices Inc.

Director

Discretionary Trading P&L

Holdings

Transaction History (26 total)

MASS
908 Devices Inc.
Oct 7, 2026
Sale(S)
Direct
30K shares at avg. $11.89$357K
MASS
908 Devices Inc.
Oct 7, 2026
Exercise(M)
Direct
60K shares at avg. $1.75$105K
MASS
908 Devices Inc.
Sep 2, 2026
Sale(S)
Direct
30K shares at avg. $10.58$317K
MASS
908 Devices Inc.
Aug 11, 2026
Sale(S)
Direct
8.4K shares at avg. $9.23$77K
MASS
908 Devices Inc.
Aug 10, 2026
Sale(S)
Direct
9.4K shares at avg. $9.03$85K
MASS
908 Devices Inc.
Aug 5, 2026
Sale(S)
Direct
20K shares at avg. $8.49$170K
MASS
908 Devices Inc.
Jul 2, 2026
Sale(S)
Direct
2.2K shares at avg. $9.02$20K
MASS
908 Devices Inc.
Jun 30, 2026
Sale(S)
Direct
20K shares at avg. $8.84$177K
MASS
908 Devices Inc.
Jun 23, 2026
Sale(S)
Direct
9.9K shares at avg. $9.04$89K
MASS
908 Devices Inc.
Jun 4, 2026
Sale(S)
Direct
100 shares at avg. $9.00$900
MASS
908 Devices Inc.
Jun 3, 2026
Sale(S)
Direct
20K shares at avg. $8.73$175K
MASS
908 Devices Inc.
May 28, 2026
Sale(S)
Direct
30K shares at avg. $9.00$270K
MASS
908 Devices Inc.
May 6, 2026
Sale(S)
Direct
20K shares at avg. $7.23$145K
MASS
908 Devices Inc.
Apr 10, 2026
Sale(S)
Direct
17.6K shares at avg. $7.07$124K
MASS
908 Devices Inc.
Apr 9, 2026
Sale(S)
Direct
7.4K shares at avg. $7.04$52K
MASS
908 Devices Inc.
Apr 8, 2026
Sale(S)
Direct
15K shares at avg. $7.05$106K
MASS
908 Devices Inc.
Feb 1, 2026
Exercise(M)
Direct
5K shares-
MASS
908 Devices Inc.
Feb 1, 2026
Exercise(M)
Direct
11K shares-
MASS
908 Devices Inc.
Feb 1, 2026
Exercise(M)
Direct
7.4K shares-
MASS
908 Devices Inc.
Feb 3, 2025
Sale(S)
Direct
2.5K shares at avg. $2.34$6K
MASS
908 Devices Inc.
Feb 3, 2025
Sale(S)
Direct
1.7K shares at avg. $2.36$4K
MASS
908 Devices Inc.
Feb 3, 2025
Sale(S)
Direct
3.6K shares at avg. $2.33$9K
MASS
908 Devices Inc.
Feb 1, 2025
Exercise(M)
Direct
7.4K shares-
MASS
908 Devices Inc.
Feb 1, 2025
Exercise(M)
Direct
11K shares-
MASS
908 Devices Inc.
Feb 1, 2025
Exercise(M)
Direct
5K shares-

		Type	Shares	Price		Ownership
Oct 7, 2026	MASS 908 Devices Inc.	Sale(S)	30,000	$11.89	$356,700	Direct
Oct 7, 2026	MASS 908 Devices Inc.	Exercise(M)	60,000	$1.75	$105,000	Direct
Sep 2, 2026	MASS 908 Devices Inc.	Sale(S)	30,000	$10.58	$317,400	Direct
Aug 11, 2026	MASS 908 Devices Inc.	Sale(S)	8,358	$9.23	$77,144	Direct
Aug 10, 2026	MASS 908 Devices Inc.	Sale(S)	9,442	$9.03	$85,261	Direct
Aug 5, 2026	MASS 908 Devices Inc.	Sale(S)	20,000	$8.49	$169,800	Direct
Jul 2, 2026	MASS 908 Devices Inc.	Sale(S)	2,200	$9.02	$19,844	Direct
Jun 30, 2026	MASS 908 Devices Inc.	Sale(S)	20,000	$8.84	$176,800	Direct
Jun 23, 2026	MASS 908 Devices Inc.	Sale(S)	9,900	$9.04	$89,496	Direct
Jun 4, 2026	MASS 908 Devices Inc.	Sale(S)	100	$9.00	$900	Direct
Jun 3, 2026	MASS 908 Devices Inc.	Sale(S)	20,000	$8.73	$174,600	Direct
May 28, 2026	MASS 908 Devices Inc.	Sale(S)	30,000	$9.00	$270,000	Direct
May 6, 2026	MASS 908 Devices Inc.	Sale(S)	20,000	$7.23	$144,600	Direct
Apr 10, 2026	MASS 908 Devices Inc.	Sale(S)	17,578	$7.07	$124,276	Direct
Apr 9, 2026	MASS 908 Devices Inc.	Sale(S)	7,392	$7.04	$52,040	Direct
Apr 8, 2026	MASS 908 Devices Inc.	Sale(S)	15,030	$7.05	$105,962	Direct
Feb 1, 2026	MASS 908 Devices Inc.	Exercise(M)	5,027	-	$0	Direct
Feb 1, 2026	MASS 908 Devices Inc.	Exercise(M)	10,992	-	$0	Direct
Feb 1, 2026	MASS 908 Devices Inc.	Exercise(M)	7,418	-	$0	Direct
Feb 3, 2025	MASS 908 Devices Inc.	Sale(S)	2,459	$2.34	$5,763	Direct
Feb 3, 2025	MASS 908 Devices Inc.	Sale(S)	1,667	$2.36	$3,926	Direct
Feb 3, 2025	MASS 908 Devices Inc.	Sale(S)	3,641	$2.33	$8,501	Direct
Feb 1, 2025	MASS 908 Devices Inc.	Exercise(M)	7,418	-	-	Direct
Feb 1, 2025	MASS 908 Devices Inc.	Exercise(M)	10,991	-	-	Direct
Feb 1, 2025	MASS 908 Devices Inc.	Exercise(M)	5,027	-	-	Direct

1-25 of 26 transactions

About Brown Christopher D.

Brown Christopher D. (SEC CIK 0001836988) files insider reports with the SEC as Director of 908 Devices Inc. (MASS).

Signal8 holds 16 ownership filings by Brown Christopher D. (1 Form 3, 15 Form 4), filed between Dec 19, 2024 and Oct 9, 2026. Those filings report 26 transactions, from Dec 19, 2024 to Oct 7, 2026. Signal8's Form 4 history starts in Sep 2024.

The business address on Brown Christopher D.'s filings is in BURLINGTON, MA.

Recent filings by Brown Christopher D.

Oct 7, 2026: Open-market sale of MASS shares (Form 4, code S).
Oct 7, 2026: Option exercise of MASS shares (Form 4, code M).
Sep 2, 2026: Open-market sale of MASS shares (Form 4, code S).
Aug 11, 2026: Open-market sale of MASS shares (Form 4, code S).
Aug 10, 2026: Open-market sale of MASS shares (Form 4, code S).

Other insiders filing for 908 Devices Inc. (MASS)

Griffith Joseph H. IV, Chief Financial Officer
AWM Investment Company, Inc., 10% Owner
Kenneweg John, SVP, Sales & Product Marketing
Knopp Kevin J., President and CEO
Vann Brandi C, Director
Leonhart Michele M., Director

How to read Form 4 transaction codes