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Insider Trading Intelligence
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CB

Christopher D. Brown

MASS
CHIEF TECHNOLOGY OFFICER · 908 DEVICES INC. · CIK 0001836988
FILING MIX · LIFETIME24%/76%
BUYS
19
SELLS
59
TOTAL VALUE
$7.00M
COMPANIES
1
ACTIVE SINCE
Dec 2020
HOLDINGS NOW
845,559
AVG SELL PX
$17.55
TRADE KIND
SHOWING 78 / 78
Trades · vs SPY
Loading price series…
Performance · forward returns vs SPY
41 backtested trades · 8 horizons · 20 pending
Forward-return performance of every backtestable P/S trade by Christopher D. Brown, measured at 8 horizons from 7 days to 2 years. Deduped per economic event so co-filings count once. Excess return = trade return minus SPY return over the same window.
HORIZONTRADESWIN RATEINSIDER RETURNSPY RETURNMEAN EXCESSMEDIAN EXCESST-STAT
7d41+51.22%+0.57%+1.06%-0.49%-1.83%-0.35
14d41+43.90%-1.63%+0.97%-2.24%-1.36%-1.35
30d41+46.34%+1.25%+1.89%-0.64%+0.07%-0.21
60d41(1 pending)+70.00%-5.27%+0.77%-6.04%-11.37%-1.32
90d41(4 pending)+75.68%-9.25%+0.37%-9.62%-23.82%-1.22
180d41(4 pending)+89.19%-18.93%+2.26%-21.19%-38.47%-2.04
1y41(4 pending)+91.89%-34.53%+4.76%-39.29%-49.45%-3.58
2y41(7 pending)+100.00%-65.06%+23.66%-88.73%-83.70%-25.49
How to read this: Insider Returnis the average raw return of the filer's trades over the horizon. SPY Return is what SPY did over those same windows — reference only, not a comparison. The headline alpha number is Mean Excess = Insider − SPY; green means the filer beat SPY, red means they trailed it. Win rate is the share of individual trades where the filer beat SPY. T-statvalues above 2 mean the alpha is unlikely to be chance given the sample size. "Pending" counts trades where the horizon hasn't elapsed yet; their stats are not included in the row average.
Holdings over time
MASS · 845,559 shares · as of Jun 30, 2026
0275,978551,956827,9341,103,912202120222023202420252026SHARES HELD
Trading cadence · quarterly flow
BUY ● SELL ●
2020
2021
2021
2021
2021
2022
2022
2022
2022
2023
2023
2023
2023
2024
2024
2024
2024
2025
2025
2025
2025
2026
2026
FLOW · 19 buys / 59 sellsCOVERAGE · 23 quarters
Form 4 filings · all activity
COMPANYTYPESHARESPRICEVALUEHELD AFTERTRADE DATEFILEDDETAILS
MASS
908 DEVICES INC.
SALE10b5-1
10b5-1 plan
20,000$8.84$176.8K845,559Jun 30, 2026Jul 2, 2026 ↗View →
MASS
908 DEVICES INC.
SALE10b5-1
10b5-1 plan
9,900$9.04$89.5K865,559Jun 23, 2026Jun 25, 2026 ↗View →
MASS
908 DEVICES INC.
SALE10b5-1
10b5-1 plan
100$9.00$900875,459Jun 4, 2026Jun 5, 2026 ↗View →
MASS
908 DEVICES INC.
SALE10b5-1
10b5-1 plan
20,000$8.73$174.6K875,559Jun 3, 2026Jun 4, 2026 ↗View →
MASS
908 DEVICES INC.
SALE10b5-1
10b5-1 plan
30,000$9.00$270.0K895,559May 28, 2026May 29, 2026 ↗View →
MASS
908 DEVICES INC.
SALE10b5-1
10b5-1 plan
20,000$7.23$144.6K925,559May 6, 2026May 7, 2026 ↗View →
MASS
908 DEVICES INC.
SALE10b5-1
10b5-1 plan
17,578$7.07$124.3K945,559Apr 10, 2026Apr 10, 2026 ↗View →
MASS
908 DEVICES INC.
SALE10b5-1
10b5-1 plan
7,392$7.04$52.0K963,137Apr 9, 2026Apr 10, 2026 ↗View →
MASS
908 DEVICES INC.
SALE10b5-1
10b5-1 plan
15,030$7.05$106.0K970,529Apr 8, 2026Apr 10, 2026 ↗View →
MASS
908 DEVICES INC.
PURCHASE
5,027——967,149Feb 1, 2026Feb 3, 2026 ↗View →
MASS
908 DEVICES INC.
PURCHASE
10,992——985,559Feb 1, 2026Feb 3, 2026 ↗View →
MASS
908 DEVICES INC.
SALE
7,418——7,418Feb 1, 2026Feb 3, 2026 ↗View →
MASS
908 DEVICES INC.
PURCHASE
7,418——974,567Feb 1, 2026Feb 3, 2026 ↗View →
MASS
908 DEVICES INC.
SALE
5,027——0Feb 1, 2026Feb 3, 2026 ↗View →
MASS
908 DEVICES INC.
SALE
10,992——21,982Feb 1, 2026Feb 3, 2026 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Product Officer
1,667$2.36$3.9K968,222Feb 3, 2025Feb 4, 2025 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Product Officer
2,459$2.34$5.8K965,763Feb 3, 2025Feb 4, 2025 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Product Officer
3,641$2.33$8.5K962,122Feb 3, 2025Feb 4, 2025 ↗View →
MASS
908 DEVICES INC.
PURCHASE
Chief Product Officer
5,027——951,480Feb 1, 2025Feb 4, 2025 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Product Officer
5,027——5,027Feb 1, 2025Feb 4, 2025 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Product Officer
10,991——32,974Feb 1, 2025Feb 4, 2025 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Product Officer
7,418——14,836Feb 1, 2025Feb 4, 2025 ↗View →
MASS
908 DEVICES INC.
PURCHASE
Chief Product Officer
10,991——969,889Feb 1, 2025Feb 4, 2025 ↗View →
MASS
908 DEVICES INC.
PURCHASE
Chief Product Officer
7,418——958,898Feb 1, 2025Feb 4, 2025 ↗View →
MASS
908 DEVICES INC.
PURCHASE
Chief Product Officer
55,131$1.58$87.1K946,453Dec 19, 2024Dec 19, 2024 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Product Officer
55,131——0Dec 19, 2024Dec 19, 2024 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Product Officer
6,328——55,131Aug 7, 2024Aug 8, 2024 ↗View →
MASS
908 DEVICES INC.
PURCHASE
Chief Product Officer
6,328$1.58$10.0K891,322Aug 7, 2024Aug 8, 2024 ↗View →
MASS
908 DEVICES INC.
PURCHASE
Chief Product Officer
3,600$1.75$6.3K884,994Apr 1, 2024Apr 2, 2024 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Product Officer
3,600——114,318Apr 1, 2024Apr 2, 2024 ↗View →
MASS
908 DEVICES INC.
PURCHASEGRANT
Stock grant
60,064——60,064Mar 1, 2024Mar 5, 2024 ↗View →
MASS
908 DEVICES INC.
PURCHASEGRANT
Stock grant
43,965——43,965Mar 1, 2024Mar 5, 2024 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Product Officer
1,599$6.99$11.2K888,752Feb 1, 2024Feb 2, 2024 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Product Officer
5,028——10,054Feb 1, 2024Feb 2, 2024 ↗View →
MASS
908 DEVICES INC.
PURCHASE
Chief Product Officer
7,418——890,351Feb 1, 2024Feb 2, 2024 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Product Officer
2,358$7.02$16.5K886,394Feb 1, 2024Feb 2, 2024 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Product Officer
7,418——22,254Feb 1, 2024Feb 2, 2024 ↗View →
MASS
908 DEVICES INC.
PURCHASE
Chief Product Officer
5,028——882,933Feb 1, 2024Feb 2, 2024 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Product Officer
7,370$9.12$67.2K877,905Dec 21, 2023Dec 21, 2023 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Product Officer
5,235$9.10$47.6K885,275Dec 20, 2023Dec 21, 2023 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Product Officer
6,090$9.08$55.3K891,815Dec 19, 2023Dec 21, 2023 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Product Officer
1,305$9.08$11.8K890,510Dec 19, 2023Dec 21, 2023 ↗View →
MASS
908 DEVICES INC.
SALE10b5-1
10b5-1 plan
4,470$10.03$44.8K897,905Jun 7, 2023Jun 9, 2023 ↗View →
MASS
908 DEVICES INC.
SALE10b5-1
10b5-1 plan
10,000$10.02$100.2K892,375May 23, 2023May 25, 2023 ↗View →
MASS
908 DEVICES INC.
PURCHASEGRANT
Stock grant
29,672——29,672Mar 1, 2023Mar 16, 2023 ↗View →
MASS
908 DEVICES INC.
PURCHASEGRANT
Stock grant
45,018——45,018Mar 1, 2023Mar 16, 2023 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
10,000$10.03$100.3K902,375Feb 2, 2023Feb 3, 2023 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
1,564$9.17$14.3K912,375Feb 1, 2023Feb 3, 2023 ↗View →
MASS
908 DEVICES INC.
PURCHASE
Chief Technology Officer
5,027——913,939Feb 1, 2023Feb 3, 2023 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
5,027——15,082Feb 1, 2023Feb 3, 2023 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
20,000$19.58$391.6K908,912Sep 12, 2022Sep 14, 2022 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
6,800$21.04$143.1K932,112Jul 6, 2022Jul 8, 2022 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
3,200$21.78$69.7K928,912Jul 6, 2022Jul 8, 2022 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
3,700$20.12$74.4K938,912Jun 30, 2022Jul 1, 2022 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
16,471$20.22$333.0K942,612Jun 29, 2022Jul 1, 2022 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
9,829$20.06$197.2K959,083Apr 12, 2022Apr 14, 2022 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
19,900$20.06$399.2K968,912Mar 18, 2022Mar 21, 2022 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
100$20.00$2.0K988,812Mar 11, 2022Mar 15, 2022 ↗View →
MASS
908 DEVICES INC.
PURCHASEGRANT
Stock grant
33,400——33,400Mar 1, 2022Mar 3, 2022 ↗View →
MASS
908 DEVICES INC.
PURCHASEGRANT
Stock grant
20,109——20,109Mar 1, 2022Mar 3, 2022 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
6,714$24.05$161.5K988,912Jan 5, 2022Jan 7, 2022 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
3,286$22.89$75.2K995,626Jan 5, 2022Jan 7, 2022 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
8,770$23.80$208.7K1,000,142Dec 1, 2021Dec 3, 2021 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
1,230$24.29$29.9K998,912Dec 1, 2021Dec 3, 2021 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
3,426$33.24$113.9K1,008,912Nov 3, 2021Nov 4, 2021 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
11,574$32.75$379.0K1,012,338Nov 3, 2021Nov 4, 2021 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
1,580$33.33$52.7K1,023,912Oct 6, 2021Oct 7, 2021 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
13,420$32.19$432.0K1,025,492Oct 6, 2021Oct 7, 2021 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
8,685$35.68$309.9K1,045,227Sep 1, 2021Sep 3, 2021 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
6,315$36.24$228.9K1,038,912Sep 1, 2021Sep 3, 2021 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
5,400$33.40$180.4K1,053,912Aug 4, 2021Aug 6, 2021 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
5,100$32.47$165.6K1,059,312Aug 4, 2021Aug 6, 2021 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
4,500$31.58$142.1K1,064,412Aug 4, 2021Aug 6, 2021 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
200$34.99$7.0K1,068,912Jul 7, 2021Jul 8, 2021 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
29,765$33.52$997.7K1,074,147Jul 7, 2021Jul 8, 2021 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
5,035$34.25$172.4K1,069,112Jul 7, 2021Jul 8, 2021 ↗View →
MASS
908 DEVICES INC.
PURCHASE
Chief Technology Officer
4,396——1,103,912Dec 22, 2020Dec 22, 2020 ↗View →
MASS
908 DEVICES INC.
SALE
Chief Technology Officer
4,396——0Dec 22, 2020Dec 22, 2020 ↗View →
Other insiders · MASS
Loading peer insiders…
About this filer
CIK 0001836988
ROLE
Chief Technology Officer
PRIMARY
MASS
COMPANIES
1
ACTIVE SINCE
Dec 2020
MARKETPEEL · /INSIDER/0001836988DATA · SEC EDGAR · FORM 4 · CONSOLIDATED TAPE
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