John Kenneweg - 01 May 2026 Form 4 Insider Report for 908 Devices Inc. (MASS)

Reporting relationship: SVP, Sales & Product Marketing
Issuer ticker: MASS
Reported as of: 01 May 2026
Net transaction value: -$53,185
SEC form: 4
Accepted by SEC: 04 May 2026, 16:30:16 UTC
Prior SEC filing: 29 Apr 2026
Next SEC filing: 11 May 2026
Source filing: View source filing
Reporting owner signature: /s/ Mark S. Levine, Attorney-in-Fact

Key filing fact

John Kenneweg filed Form 4 for 908 Devices Inc. (MASS) on 04 May 2026.

Key facts

This page summarizes John Kenneweg's Form 4 filing for 908 Devices Inc. (MASS).
3 reported transactions and 1 derivative row are listed below.
Accepted by SEC: 04 May 2026, 16:30.

Change

Previous filing in this sequence was filed on 29 Apr 2026.
Current net transaction value: -$53,185.

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

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

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: 04 May 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: +26,042
Change %: +45%
Price
Shares after: 83,826
Date: 01 May 2026
Ownership: Direct
Footnotes: F1

MASS transaction

Common Stock

Sale

Transaction value: $53,185
Shares: -7,787
Change %: -9.3%
Price: $6.83
Shares after: 76,039
Date: 01 May 2026
Ownership: Direct
Footnotes: F2

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

MASS transaction Derivative

Performance Stock Units

Options Exercise

Transaction value
Shares: -26,042
Change %: -100%
Price: $0.000000^*
Shares after: 0
Date: 01 May 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 26,042
Exercise price
Footnotes: F1, F3

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 3 footnotes

Footnote F1

Each performance stock unit ("PSU") represents a contingent right to receive one share of Common Stock, par value $0.001, when vested.

Footnote 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 PSUs. 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.

Footnote F3

The PSUs vested, in accordance with their terms, on May 1, 2026. The PSUs had no expiration date.