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908 Devices Inc. (NASDAQ:MASS)
US · Delayed Price · Currency is USD
Healthcare · Medical - Specialties
11.65+0.16 (+1.39%)
Market cap
$482M
Health Score
Analyst consensus
Listed since
Dec 18, 2020
Website
Insider Score
––Not scored
MASS Insider Score
Insiders filed in the last 90 days, but none of those trades qualified for scoring — round-trip buys and filings whose price is far off the market are excluded.
MASS Stock Insider Trading Activity
MASS stock’s insider trading shows 23 sales on the open market for an estimated $4.68M by company insiders over the last 6 months.
Not enough price history.
Insider Trading Activity (Form 4 Filings)
An insider trade occurs when an individual that has non-public information about a company buys or sells shares of that company’s stock. Examples of insiders include a company’s executive officers (CEO, CFO, COO), its board of directors, and its major shareholders. Insiders are required to submit their trading activity to the SEC through Form 4 filings.
Scored window · last 90 days0 qualifying buys0 insiders$0 bought— these are the numbers in the rankings table; the full history below shows every filing (buys, sells and older activity).
| Insider | Action | Shares | Avg Cost | Total | Δ Holdings | Held After | Date | Grade | Form 4 |
|---|---|---|---|---|---|---|---|---|---|
| Brown Christopher D. Director | Option exercise | 60,000 | $1.75 | $105.00K | 8.0% | 805,559 | Oct 7, 2026 | — | Form 4 |
| Brown Christopher D. Director | Sell | 30,000 | $11.89 | $356.70K | 3.9% | 745,559 | Oct 7, 2026 | — | Form 4 |
| Griffith Joseph H. IV CFO | Sell | 5,000 | $13.03 | $65.15K | 4.1% | 116,497 | Oct 6, 2026 | — | Form 4 |
| AWM Investment Company, Inc. Other | Sell | 18,000 | $11.52 | $207.32K | 0.4% | 4,736,773 | Sep 29, 2026 | — | Form 4 |
| AWM Investment Company, Inc. Other | Sell | 24,000 | $11.36 | $272.63K | 0.5% | 4,754,773 | Sep 24, 2026 | — | Form 4 |
| AWM Investment Company, Inc. Other | Sell | 1,000 | $11.25 | $11.25K | 0.0% | 4,755,773 | Sep 23, 2026 | — | Form 4 |
| Kenneweg John Other | Option exercise | 5,257 | $0.96 | $5.05K | 9.1% | 63,041 | Sep 17, 2026 | — | Form 4 |
| Kenneweg John Other | Sell | 5,257 | $10.22 | $53.73K | 8.3% | 57,784 | Sep 17, 2026 | — | Form 4 |
| Kenneweg John Other | Sell | 21,399 | $10.11 | $216.34K | 27.0% | 57,784 | Sep 16, 2026 | — | Form 4 |
| Kenneweg John Other | Option exercise | 21,399 | $0.96 | $20.54K | 37.0% | 79,183 | Sep 16, 2026 | — | Form 4 |
| Kenneweg John Other | Sell | 1,000 | $10.00 | $10.00K | 1.7% | 57,784 | Sep 15, 2026 | — | Form 4 |
| Kenneweg John Other | Option exercise | 1,000 | $0.96 | $960 | 1.7% | 58,784 | Sep 15, 2026 | — | Form 4 |
| Brown Christopher D. Director | Sell | 30,000 | $10.58 | $317.40K | 3.7% | 775,559 | Sep 2, 2026 | — | Form 4 |
| Griffith Joseph H. IV CFO | Sell | 11,459 | $10.95 | $125.48K | 8.6% | 121,497 | Aug 25, 2026 | — | Form 4 |
| AWM Investment Company, Inc. Other | Sell | 41,578 | $10.61 | $441.16K | 0.9% | 4,779,773 | Aug 21, 2026 | — | Form 4 |
| AWM Investment Company, Inc. Other | Sell | 8,422 | $10.52 | $88.64K | 0.2% | 4,821,351 | Aug 20, 2026 | — | Form 4 |
| Knopp Kevin J. CEO | Sell | 20,000 | $10.35 | $207.00K | 3.5% | 555,968 | Aug 17, 2026 | — | Form 4 |
| Knopp Kevin J. CEO | Sell | 7,622 | $10.06 | $76.68K | 1.3% | 575,968 | Aug 13, 2026 | — | Form 4 |
| Knopp Kevin J. CEO | Sell | 2,747 | $10.07 | $27.66K | 0.5% | 583,590 | Aug 12, 2026 | — | Form 4 |
| Knopp Kevin J. CEO | Sell | 115,748 | $9.83 | $1.14M | 15.8% | 616,507 | Aug 11, 2026 | — | Form 4 |
| Brown Christopher D. Director | Sell | 8,358 | $9.23 | $77.14K | 1.0% | 805,559 | Aug 11, 2026 | — | Form 4 |
| Knopp Kevin J. CEO | Sell | 30,170 | $10.16 | $306.53K | 4.9% | 586,337 | Aug 11, 2026 | — | Form 4 |
| Knopp Kevin J. CEO | Sell | 348 | $9.06 | $3.15K | 0.0% | 732,255 | Aug 10, 2026 | — | Form 4 |
| Brown Christopher D. Director | Sell | 9,442 | $9.03 | $85.26K | 1.1% | 813,917 | Aug 10, 2026 | — | Form 4 |
| Brown Christopher D. Director | Sell | 20,000 | $8.49 | $169.80K | 2.4% | 823,359 | Aug 5, 2026 | — | Form 4 |
| AWM Investment Company, Inc. Other | Sell | 50,000 | $8.36 | $417.76K | 1.0% | 4,829,773 | Aug 4, 2026 | — | Form 4 |
| Vann Brandi C Director | Option exercise | 5,192 | — | — | New | 5,192 | Aug 1, 2026 | — | Form 4 |
| Knopp Kevin J. CEO | Sell | 222 | $9.07 | $2.01K | 0.0% | 732,603 | Jul 2, 2026 | — | Form 4 |
What these mean— the action is the SEC’s own Form 4 transaction code. Only a buy or a sell is an open-market trade; the rest are transfers, awards and exercises, which is why they carry no price.
- Sell (S) — Open-market or private sale
- Option exercise (M) — Exercise or conversion of an exempt derivative
Disclaimer — Informational only — not investment advice. Insider transaction data is sourced from SEC Form 4 filings; market data from public feeds and may be delayed. The Insider Score is a proprietary score for research purposes and does not predict future performance. Always do your own research.