Key facts
- This page summarizes John Kenneweg's Form 4 filing for 908 Devices Inc. (MASS).
- 9 reported transactions and 3 derivative rows are listed below.
- Accepted by SEC: 17 Sep 2026, 17:27.
John Kenneweg - 15 Sep 2026 Form 4 Insider Report for 908 Devices Inc. (MASS)
- Reporting relationship
- SVP, Sales & Product Marketing
- Issuer ticker
- MASS
- Reported as of
- 15 Sep 2026
- Net transaction value
- -$280,070
- SEC form
- 4
- Accepted by SEC
- 17 Sep 2026, 17:27:45 UTC
- Prior SEC filing
- 11 May 2026
- Source filing
- View source filing
- Reporting owner signature
- /s/ Mark S. Levine, Attorney-in-Fact
Source evidence
Original filing metadata and source links for verification.
4 source fields
Reporting owner
1 detail
Key filing fact
John Kenneweg filed Form 4 for 908 Devices Inc. (MASS) on 17 Sep 2026.
Change
- Previous filing in this sequence was filed on 11 May 2026.
- Current net transaction value: -$280,070.
Research use
- This tells you what this filing adds before you inspect full transaction and derivative tables.
- You can trace every row back to the original SEC filing document.
Evidence
Filed on Form 4
View source filing
Ownership activity is grounded in SEC Form 4 disclosures.
Reporting Owners (1)
CIK 0001836876
Primary reporting owner
Kenneweg John
- Relationship
- SVP, Sales & Product Marketing
- Address
- C/O 908 DEVICES INC., 44 3RD AVENUE, BURLINGTON
- Signature
- /s/ Mark S. Levine, Attorney-in-Fact
- Signature date
- 17 Sep 2026
Reported non-derivative transactions
Shares, units, or other non-derivative securities reported in this filing.
MASS
transaction
Common Stock
Options Exercise
- Transaction value
- Shares
- +1,000
- Change %
- +1.7%
- Price
- $0.9600*
- Shares after
- 58,784
- Date
- 15 Sep 2026
- Ownership
- Direct
- Footnotes
- F1
MASS
transaction
Common Stock
Sale
- Transaction value
- $10,000
- Shares
- -1,000
- Change %
- -1.7%
- Price
- $10.00
- Shares after
- 57,784
- Date
- 15 Sep 2026
- Ownership
- Direct
- Footnotes
- F1
MASS
transaction
Common Stock
Options Exercise
- Transaction value
- Shares
- +21,399
- Change %
- +37%
- Price
- $0.9600*
- Shares after
- 79,183
- Date
- 16 Sep 2026
- Ownership
- Direct
- Footnotes
- F1
MASS
transaction
Common Stock
Sale
- Transaction value
- $216,344
- Shares
- -21,399
- Change %
- -27%
- Price
- $10.11
- Shares after
- 57,784
- Date
- 16 Sep 2026
- Ownership
- Direct
- Footnotes
- F1, F2
MASS
transaction
Common Stock
Options Exercise
- Transaction value
- Shares
- +5,257
- Change %
- +9.1%
- Price
- $0.9600*
- Shares after
- 63,041
- Date
- 17 Sep 2026
- Ownership
- Direct
- Footnotes
- F1
MASS
transaction
Common Stock
Sale
- Transaction value
- $53,727
- Shares
- -5,257
- Change %
- -8.3%
- Price
- $10.22
- Shares after
- 57,784
- Date
- 17 Sep 2026
- Ownership
- Direct
- Footnotes
- F1, F3
Reported derivative securities
Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.
MASS
transaction
Derivative
Stock Option (right to buy)
Options Exercise
- Transaction value
- Shares
- -1,000
- Change %
- -3.6%
- Price
- $0.000000*
- Shares after
- 26,656
- Date
- 15 Sep 2026
- Ownership
- Direct
- Underlying class
- Common Stock
- Underlying amount
- 1,000
- Exercise price
- $0.9600
- Footnotes
- F1, F4
MASS
transaction
Derivative
Stock Option (right to buy)
Options Exercise
- Transaction value
- Shares
- -21,399
- Change %
- -80%
- Price
- $0.000000*
- Shares after
- 5,257
- Date
- 16 Sep 2026
- Ownership
- Direct
- Underlying class
- Common Stock
- Underlying amount
- 21,399
- Exercise price
- $0.9600
- Footnotes
- F1, F4
MASS
transaction
Derivative
Stock Option (right to buy)
Options Exercise
- Transaction value
- Shares
- -5,257
- Change %
- -100%
- Price
- $0.000000*
- Shares after
- 0
- Date
- 17 Sep 2026
- Ownership
- Direct
- Underlying class
- Common Stock
- Underlying amount
- 5,257
- Exercise price
- $0.9600
- Footnotes
- F1, F4
* marks a reported price that did not pass the local price check.
Additional SEC filing notes
Filing notes and footnotes
Rule 10b5-1 trading plan
These transactions were reported as open-market trades under a Rule 10b5-1 plan. The plan lets an insider set trading instructions in advance, which can reduce the risk of trading while in possession of material nonpublic information.
Original filing language: transaction made pursuant to a contract, instruction, or written plan intended to satisfy Rule 10b5-1(c).
Explanation of responses 4 footnotes
Footnote F1
This transaction was made pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on June 12, 2026.
Footnote F2
The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $10.00 to $10.32 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the 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 range set forth in this footnote.
Footnote F3
The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $10.13 to $10.29 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the 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 range set forth in this footnote.
Footnote F4
The shares underlying the option are fully vested and immediately exercisable.