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MASS Insider Trading: 908 Devices Inc. Insider Buys and Sells · https://wallstpal.com/stock/mass/insider-trading/ · saved 2026-10-28

About this page

Insider trades reported on SEC Form 4: when the people who run a company buy or sell its shares with their own money.

How to read it

Form 4
The form a company insider (officer, director or owner of more than 10%) must file with the SEC within two business days of buying or selling the company's shares.
Buy (P) and Sell (S)
Open-market purchases and sales. Gifts, option exercises and automatic tax withholding are left out because they say little about what the insider thinks.
Value
Shares times price, as reported on the filing.
10b5-1
A trade made under a plan set up in advance. Planned sales are common and usually say less than an unplanned purchase.
Late filing
A Form 4 filed more than two business days after the trade.
Vs. S&P 500
How the stock did after the trade minus how the overall market did in the same weeks.

A real example

In January 2016, when bank stocks were falling, JPMorgan Chase CEO Jamie Dimon bought 500,000 JPMorgan shares with his own money, worth about $26 million. His Form 4 made the purchase public within days, and investors read it as a strong sign of confidence.

Explain it like I'm 13

If the coach of a team bets his own allowance that his team will win, that tells you something. A Form 4 is the note a company boss must hand in whenever he buys or sells his own company's shares, so everyone can see it.

Data from public SEC filings and congressional reports. Information, not investment advice. Check every number against the filing linked on the page.

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Insider tradingForm 4

908 Devices Inc. (MASS) Insider Trading

31 open-market trades reported since Jun 24, 2026: 0 purchases worth $0 and 31 sales worth $5.61M.

By insider

InsiderRoleBuysBoughtSellsSoldLatest
Christopher D. BrownDirector0$08$1.29MOct 9, 2026
Joseph H. Griffith IVCFO0$02$191KOct 8, 2026
Awm Investment Company, Inc.10% owner0$08$1.51MOct 1, 2026
John KennewegSVP0$03$280KSep 17, 2026
Kevin J. KnoppCEO0$010$2.34MAug 17, 2026

All trades

MASS insider trades
FiledTradedInsiderRoleTypeSharesPrice ($)ValueHolding3 mo. afterFiling
Oct 9Oct 7Christopher D. BrownDirectorDirector▼ SELL10b5-130,00011.89$357K−3.9%Form 4 ↗
Oct 8Oct 6Joseph H. Griffith IVCFOCFO▼ SELL10b5-15,00013.03$65K−4.1%Form 4 ↗
Oct 1Sep 29Awm Investment Company, Inc.10% owner10% owner (ind.)▼ SELL18,00011.52$207K−0.4%Form 4 ↗
Sep 25Sep 24Awm Investment Company, Inc.10% owner10% owner (ind.)▼ SELL24,00011.36$273K−0.5%Form 4 ↗
Sep 25Sep 23Awm Investment Company, Inc.10% owner10% owner (ind.)▼ SELL1,00011.25$11K+0.0%Form 4 ↗
Sep 17Sep 16John KennewegSVPSVP▼ SELL10b5-121,39910.11$216K−27%Form 4 ↗
Sep 17Sep 17John KennewegSVPSVP▼ SELL10b5-15,25710.22$54K−8.3%Form 4 ↗
Sep 17Sep 15John KennewegSVPSVP▼ SELL10b5-11,00010.00$10K−1.7%Form 4 ↗
Sep 4Sep 2Christopher D. BrownDirectorDirector▼ SELL10b5-130,00010.58$317K−3.7%Form 4 ↗
Aug 27Aug 25Joseph H. Griffith IVCFOCFO▼ SELL10b5-111,45910.95$125K−8.6%Form 4 ↗
Aug 24Aug 21Awm Investment Company, Inc.10% owner10% owner (ind.)▼ SELL41,57810.61$441K−0.9%Form 4 ↗
Aug 24Aug 20Awm Investment Company, Inc.10% owner10% owner (ind.)▼ SELL8,42210.52$89K−0.2%Form 4 ↗
Aug 17Aug 17Kevin J. KnoppCEOCEO▼ SELL10b5-120,00010.35$207K−3.5%Form 4 ↗
Aug 17Aug 13Kevin J. KnoppCEOCEO▼ SELL10b5-17,62210.06$77K−1.3%Form 4 ↗
Aug 12Aug 11Kevin J. KnoppCEOCEO▼ SELL10b5-1145,9189.90$1.44M−20%Form 4 ↗
Aug 12Aug 10Christopher D. BrownDirectorDirector▼ SELL10b5-19,4429.03$85K−1.1%Form 4 ↗
Aug 12Aug 11Christopher D. BrownDirectorDirector▼ SELL10b5-18,3589.23$77K−1.0%Form 4 ↗
Aug 12Aug 12Kevin J. KnoppCEOCEO▼ SELL10b5-12,74710.07$28K−0.5%Form 4 ↗
Aug 12Aug 10Kevin J. KnoppCEOCEO▼ SELL10b5-13489.06$3K+0.0%Form 4 ↗
Aug 7Aug 5Christopher D. BrownDirectorDirector▼ SELL10b5-120,0008.49$170K−2.4%Form 4 ↗
Aug 6Aug 4Awm Investment Company, Inc.10% owner10% owner (ind.)▼ SELL50,0008.36$418K−1.0%Form 4 ↗
Jul 7Jul 2Christopher D. BrownDirectorDirector▼ SELL10b5-12,2009.02$20K−0.3%Form 4 ↗
Jul 7Jul 2Kevin J. KnoppCEOCEO▼ SELL10b5-12229.07$2K+0.0%Form 4 ↗
Jul 2Jun 30Christopher D. BrownDirectorDirector▼ SELL10b5-120,0008.84$177K−2.3%Form 4 ↗
Jun 30Jun 26Kevin J. KnoppCEOCEO▼ SELL10b5-12,7989.09$25K−0.4%Form 4 ↗
Jun 25Jun 24Kevin J. KnoppCEOCEO▼ SELL10b5-140,5359.14$370K−5.1%Form 4 ↗
Jun 25Jun 25Kevin J. KnoppCEOCEO▼ SELL10b5-116,3889.10$149K−2.2%Form 4 ↗
Jun 25Jun 23Christopher D. BrownDirectorDirector▼ SELL10b5-19,9009.04$89K−1.1%Form 4 ↗
Jun 25Jun 23Kevin J. KnoppCEOCEO▼ SELL10b5-13,4229.06$31K−0.4%Form 4 ↗
Jun 24Jun 22Awm Investment Company, Inc.10% owner10% owner (ind.)▼ SELL4,6688.99$42K−0.1%Form 4 ↗
Jun 24Jun 23Awm Investment Company, Inc.10% owner10% owner (ind.)▼ SELL3,0509.00$27K−0.1%Form 4 ↗
Source: SEC Form 4 filings, retrieved Oct 28, 2026. How we read filings