Stock Trading Canary

United States · SEC Form 4 · Snapshot date: 2026-10-18 · Built: 2026-10-18 · 中文

← United States · Coverage record

US · SEC FORM 4

Quanterix Corp

QTRX · Nasdaq · CIK 0001503274 · Healthcare · Medical Devices

INSIDER SIGNAL

57.6 / 100

2 buyers · 3 purchase transaction lines · $296.0K gross purchase

WHY THIS SIGNAL?

Buyer breadthLow
Purchase sizeModerate
RoleStrong
RecencyLow
ConvictionStrong
Score anatomy

Each bar shows the contribution to the current score; the weights and formula stay unchanged.

Cluster+14.0 / 35
Purchase size+12.3 / 25
Role+18.0 / 20
Recency+3.3 / 10
Conviction+10.0 / 10

What is holding the score back?

  • ⚠ Cluster breadth is moderate · 2 insider(s), not 4+
  • ⚠ Purchase size is modest relative to the model scale
  • ⚠ Purchase activity is becoming less recent
  • ✓ Role scores high · most senior buyer: Chief Commercial Officer

Purchase-size comments are relative to the model scale. Average daily volume is a separate market-context diagnostic.

US-v1.2 ranks qualifying equity purchases under the current 180-day rules. The score is a research priority, not a return forecast or probability. Backtests have not shown that a higher US score is followed by better returns.

Insider activity timeline

Owner lanes show the latest 180 days. Symbol shape identifies the transaction type; sales remain context only.

AprMayJunJulAugSepOct
Miller Michael FrancisChief Technology Officer
○○○○○○○○○○○○○○○○○○
DONNELLY WILLIAM PDirector
○●●○○
Mendel ScottDirector
○○○
Sriram VandanaChief Financial Officer
○○○
Magovcevic-Liebisch IvanaDirector
○
Elliott Jeffrey ThomasDirector
○
● Purchase▼ Sale○ Other

Showing the six most active owners; 1 additional owner(s) remain in Form 4 evidence.

Purchase breadth & concentration

QUALIFYING BUYERS2
PURCHASE CONCENTRATION97%Largest buyer: DONNELLY WILLIAM P · $286.4K
CLUSTER BUYING · 15D1 insiderPeak activity: 2026-05-12–2026-05-12

Roles in the peak window: Chief Commercial Officer. Concentration uses priced qualifying P lines only and does not change the saved score.

SIGNAL HISTORY

57.6 / 100

Latest recorded score

↓ -0.2 ptsversus the previous recorded snapshot
  1. 58.1
  2. 58.0
  3. 57.9
  4. 57.8
  5. 57.6

Only scores saved when a full US scoring run completed are shown; gaps are not reconstructed.

Recent Form 4 activity

3Purchases
0Sales
145Other Form 4 lines
53SEC filings · 365 days
BUYING3 qualifying P line(s) · 180 days
SELLING0 sale line(s) · context only
OTHER85 exercise / withholding / award / gift / other lines
10b5-1 / PLANNEDNot detected in parsed evidence

P is an open-market or private purchase. S is a sale. M, F, A and G usually describe exercises, tax withholding, awards and gifts. These categories remain visually separate.

Market context

Market context provides additional background on recent price performance and risk. It does not affect the Insider Signal.

Price performance

1M
+31.2%
3M
-15.5%
6M
-2.4%
12M
-45.3%

Volatility & liquidity

Volatility
87.2%
Beta
—
Avg daily value
USD 2.5M

Valuation

Market cap
USD 155.1M
P/E
—

Fundamentals

Profit margin
-77.2%
ROE
-36.2%
Industry
Medical Devices

Market data

Price data up to: 2026-10-11 · Price source: OpenBB/yfinance; volume from price cache (yfinance) · From SEC filings: Market cap, Profit margin, ROE · Fiscal year ended: 2025-12-31 · Market cap is the shares outstanding stated on the filing cover multiplied by the latest close. Share count date: 2026-08-03 · Status: PASS

Short interest

Short interest is external context reported to FINRA by broker-dealers. It does not affect the Insider Signal.

Shares short
5,046,958
Previous report
4,976,711
Avg daily volume
679,618
Days to cover
7.4

FINRA settlement date: 2026-09-30 · Captured 2026-10-12 · FINRA equity short interest ↗. A share count, published about a week after each of two settlement dates a month; not a percentage of shares outstanding.

Historical equity purchases

Qualifying code P transactions in the local Form 4 history, including purchases outside the current signal window.

Transaction dateReporting ownerTypeSecuritySharesAvg. priceApprox. valueSource
2026-08-13DONNELLY WILLIAM PPurchase (P)Common Stock72,245USD 2.93USD 211,678SEC filing ↗
2026-08-12DONNELLY WILLIAM PPurchase (P)Common Stock27,155USD 2.75USD 74,676SEC filing ↗
2026-05-12Meadows BenjaminPurchase (P)Common Stock3,500USD 2.77USD 9,695SEC filing ↗
2025-09-12Sriram VandanaPurchase (P)Common Stock4,150USD 4.79USD 19,878SEC filing ↗
2025-06-13WALT DAVID RPurchase (P)Common Stock123,990USD 6.14USD 761,299SEC filing ↗
2025-06-12WALT DAVID RPurchase (P)Common Stock36,010USD 6.23USD 224,342SEC filing ↗
2025-06-09Toloue MasoudPurchase (P)Common Stock45,900USD 5.42USD 248,778SEC filing ↗
2025-06-09WALT DAVID RPurchase (P)Common Stock78,131USD 5.34USD 417,220SEC filing ↗
2025-06-06WALT DAVID RPurchase (P)Common Stock131,869USD 5.43USD 716,049SEC filing ↗
2025-06-06DONNELLY WILLIAM PPurchase (P)Common Stock93,113USD 5.44USD 506,535SEC filing ↗
2024-08-20WALT DAVID RPurchase (P)Common Stock47,000USD 13.29USD 624,630SEC filing ↗
2024-08-13Toloue MasoudPurchase (P)Common Stock19,000USD 10.90USD 207,100SEC filing ↗
2023-09-08DONNELLY WILLIAM PPurchase (P)Common Stock20,200USD 24.85USD 501,970SEC filing ↗
2022-08-15DOYLE MICHAEL APurchase (P)Common Stock15,000USD 10.16USD 152,400SEC filing ↗
2022-08-12Toloue MasoudPurchase (P)Common Stock105,000USD 10.43USD 1,095,150SEC filing ↗

Form 4 evidence

148 transaction lines in the latest 365-day window; 996 in local history.

DateOwnerTypeSecuritySharesAvg. priceApprox. valueSource
2026-10-15Miller Michael FrancisOption exercise / conversion (M)Common Stock1,558USD —USD —SEC filing ↗
2026-10-15Miller Michael FrancisTax withholding (F)Common Stock426USD 3.07USD 1,308SEC filing ↗
2026-10-02Magovcevic-Liebisch IvanaOption exercise / conversion (M)Common Stock4,224USD —USD —SEC filing ↗
Show recent Form 4 evidence (30 grouped rows)
DateOwnerTypeSecuritySharesAvg. priceApprox. valueSource
2026-10-15Miller Michael FrancisOption exercise / conversion (M)Common Stock1,558USD —USD —SEC filing ↗
2026-10-15Miller Michael FrancisTax withholding (F)Common Stock426USD 3.07USD 1,308SEC filing ↗
2026-10-02Magovcevic-Liebisch IvanaOption exercise / conversion (M)Common Stock4,224USD —USD —SEC filing ↗
2026-10-01Mendel ScottAward / grant (A)Common Stock4,398USD 3.41USD 14,997SEC filing ↗
2026-10-01DONNELLY WILLIAM PAward / grant (A)Common Stock6,964USD 3.41USD 23,747SEC filing ↗
2026-09-15Miller Michael FrancisOption exercise / conversion (M)Common Stock1,558USD —USD —SEC filing ↗
2026-09-15Miller Michael FrancisTax withholding (F)Common Stock426USD 2.72USD 1,159SEC filing ↗
2026-08-31Miller Michael FrancisOption exercise / conversion (M)Common Stock159USD —USD —SEC filing ↗
2026-08-31Miller Michael FrancisTax withholding (F)Common Stock48USD 2.67USD 128SEC filing ↗
2026-08-19Elliott Jeffrey ThomasOption exercise / conversion (M)Common Stock3,955USD —USD —SEC filing ↗
2026-08-17DONNELLY WILLIAM POption exercise / conversion (M)Common Stock2,802USD —USD —SEC filing ↗
2026-08-15Miller Michael FrancisOption exercise / conversion (M)Common Stock1,558USD —USD —SEC filing ↗
2026-08-15Miller Michael FrancisTax withholding (F)Common Stock426USD 2.59USD 1,103SEC filing ↗
2026-08-13DONNELLY WILLIAM PPurchase (P)Common Stock72,245USD 2.93USD 211,678SEC filing ↗
2026-08-12DONNELLY WILLIAM PPurchase (P)Common Stock27,155USD 2.75USD 74,676SEC filing ↗
2026-07-31Miller Michael FrancisOption exercise / conversion (M)Common Stock130USD —USD —SEC filing ↗
2026-07-31Miller Michael FrancisTax withholding (F)Common Stock39USD 3.48USD 136SEC filing ↗
2026-07-15Miller Michael FrancisOption exercise / conversion (M)Common Stock1,558USD —USD —SEC filing ↗
2026-07-15Miller Michael FrancisTax withholding (F)Common Stock426USD 4.24USD 1,806SEC filing ↗
2026-07-08Mendel ScottOption exercise / conversion (M)Common Stock8,073USD —USD —SEC filing ↗
2026-07-08LAI GOLDMAN MYLAOption exercise / conversion (M)Common Stock8,073USD —USD —SEC filing ↗
2026-07-01Mendel ScottAward / grant (A)Common Stock3,456USD 4.34USD 14,999SEC filing ↗
2026-07-01DONNELLY WILLIAM PAward / grant (A)Common Stock5,472USD 4.34USD 23,748SEC filing ↗
2026-06-30Miller Michael FrancisOption exercise / conversion (M)Common Stock130USD —USD —SEC filing ↗
2026-06-30Miller Michael FrancisTax withholding (F)Common Stock39USD 4.32USD 168SEC filing ↗
2026-06-15Sriram VandanaOption exercise / conversion (M)Common Stock1,833USD —USD —SEC filing ↗
2026-06-15Sriram VandanaTax withholding (F)Common Stock548USD 3.10USD 1,699SEC filing ↗
2026-06-15Miller Michael FrancisOption exercise / conversion (M)Common Stock1,558USD —USD —SEC filing ↗
2026-06-15Miller Michael FrancisTax withholding (F)Common Stock426USD 3.10USD 1,321SEC filing ↗
2026-05-31Miller Michael FrancisOption exercise / conversion (M)Common Stock130USD —USD —SEC filing ↗

Multiple price lines in one filing are grouped and share-weighted. Price and value are blank when a grouped filing line lacks price evidence.

Snapshot & identity

Snapshot date2026-10-18
Ranking versionUS-v1.2
Data qualityPASS ELIGIBLE · —
TickerQTRX
CIK0001503274
SectorHealthcare
IndustryMedical Devices Yahoo Finance
SEC SIC3826 Laboratory Analytical Instruments
ExchangeNasdaq

Data coverage

Local Form 4 history996 transaction lines from 2020-01-02 to 2026-10-15
23 P purchase lines · 462 S sale lines · 511 other lines
SEC company submissionsOpen SEC filings ↗

Local ledger as of 2026-10-18. Mapping status is an audit field and does not erase SEC filing evidence.