InsiderTrades

Form 4 for MASS 908 Devices Inc.

Accepted 2026-02-03 00:00:00 ET · period of report 2026-02-01 · accession 0001431531-26-000002 · SEC index · Original document

Summary rows

Aggregated the way they appear in lists: one row per insider, transaction code and security table.

X Filed Traded Ticker Insider Title Type Price Qty Owned ΔOwn Value
D 2026-02-03 2026-02-02 MASS Griffith Joseph H. IV CFO S - Sale+OE $6.18 -23.2K 139.9K -14% -$143.2K
DM 2026-02-03 2026-02-01 MASS Griffith Joseph H. IV CFO M - OptEx — +70.1K 163.1K +75% —
DM 2026-02-03 2026-02-01 MASS Griffith Joseph H. IV CFO M - OptEx $0.00 -70.1K 10.3K -87% $0
DM 2026-02-03 2026-02-02 MASS Griffith Joseph H. IV CFO A - Grant $0.00 +174.1K 53.0K New $0

Purchase Sale Sale after option exercise All abbreviations

Every reported transaction

#TableSecurityDateCodeA/DSharesPriceOwned afterOwnExercise / expiryUnderlyingFootnotes
1 Common Common Stock 2026-02-02 S D 23,175 $6.18 139,896 D — — (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.
2 Common Common Stock 2026-02-01 M A 5,102 — 98,032 D — — (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.
3 Common Common Stock 2026-02-01 M A 10,306 — 108,338 D — — (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.
4 Common Common Stock 2026-02-01 M A 11,260 — 119,598 D — — (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.
5 Common Common Stock 2026-02-01 M A 43,473 — 163,071 D — — (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.
6 Derivative Restricted Stock Units 2026-02-01 M D 11,260 $0.00 22,521 D — · — to — 11,260 Common Stock (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. (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.
7 Derivative Restricted Stock Units 2026-02-01 M D 43,473 $0.00 86,945 D — · — to — 43,473 Common Stock (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. (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.
8 Derivative Restricted Stock Units 2026-02-02 A A 121,164 $0.00 121,164 D — · — to — 121,164 Common Stock (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. (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.
9 Derivative Stock Option (option to buy) 2026-02-02 A A 52,967 $0.00 52,967 D $6.19 · — to 2036-02-01 52,967 Common Stock (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.
10 Derivative Restricted Stock Units 2026-02-01 M D 5,102 $0.00 0 D — · — to — 5,102 Common Stock (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. (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.
11 Derivative Restricted Stock Units 2026-02-01 M D 10,306 $0.00 10,306 D — · — to — 10,306 Common Stock (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. (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.