Martin D. Madaus is Director at Quanterix Corp (QTRX). They have made 37 open-market trades across 6 companies since 2006, most recently 2026-09-22.
CIK 0001310268
Unrated. We grade insiders only on stock they chose to buy on the open market. Grants, option exercises and vesting say nothing about timing, so they don't count — which is why someone can file often and still have no grade. It isn't a bad sign: unrated buys beat every graded tier below A.
9 open-market purchases totalling $3.4M since 2006, against 28 sales. Across 8 scored buys the stock is up 6.9% at ninety days, and 4.2 points ahead of the S&P over the same stretch.
8 scored purchases · one row per filing · discretionary only
| 7d | 30d | 90d | |
|---|---|---|---|
| Accuracy | 38% | 50% | 50% |
| Avg Move | -1.8% | +4.2% | +6.9% |
| Alpha | -0.8% | +3.1% | +4.2% |
| Scored | 8 | 8 | 8 |
| Ticker | Type | Traded | Filed | Price | Value | 7d Stock | 30d Stock | 90d Stock |
|---|---|---|---|---|---|---|---|---|
| RGEN | BUY | 2025-08-08 | 2025-08-12 | $112.13 | $202K | +2.0% | -2.3% | +19.1% |
| HOLX | BUY | 2025-05-07 | 2025-05-09 | $55.24 | $602K | -5.5% | +11.3% | +17.1% |
| AZTA | BUY | 2024-11-19 | 2024-11-19 | $40.77 | $403K | +6.3% | +11.4% | -0.1% |
| RGEN | BUY | 2024-06-14 | 2024-06-14 | $124.79 | $316K | -0.8% | -3.9% | +11.2% |
| RGEN | BUY | 2023-05-04 | 2023-05-08 | $158.84 | $238K | +1.0% | +11.4% | +10.5% |
| QTRX | BUY | 2022-08-10 | 2022-08-10 | $8.43 | $1.5M | -4.7% | +7.7% | -0.5% |
| QTRX | SELL | 2020-11-04 | 2020-11-06 | $41.33 | $180K | -8.7% | -6.3% | +57.4% |
| QTRX | SELL | 2020-10-19 | 2020-10-20 | $43.58 | $139K | -10.5% | +12.4% | +93.5% |
| QTRX | SELL | 2020-10-06 | 2020-10-08 | $36.82 | $118K | -10.9% | -6.6% | +2.4% |
| QTRX | SELL | 2020-09-28 | 2020-09-30 | $32.90 | $158K | +32.4% | +7.8% | +35.1% |
| QTRX | SELL | 2020-09-16 | 2020-09-17 | $32.92 | $158K | +0.8% | +27.0% | +30.5% |
| QTRX | SELL | 2020-09-01 | 2020-09-03 | $35.27 | $169K | +1.0% | +7.5% | +32.5% |
| QTRX | SELL | 2020-08-18 | 2020-08-20 | $34.65 | $166K | -4.9% | -11.0% | +24.0% |
| QTRX | SELL | 2020-08-05 | 2020-08-05 | $32.89 | $105K | -0.7% | -11.4% | +12.3% |
| QTRX | SELL | 2020-07-20 | 2020-07-22 | $31.25 | $100K | +8.5% | +21.2% | +37.5% |
| QTRX | SELL · 10b5-1 | 2020-07-08 | 2020-07-10 | $26.93 | $86K | +9.3% | +21.2% | +65.3% |
| QTRX | SELL · 10b5-1 | 2020-06-24 | 2020-06-26 | $26.24 | $84K | +1.1% | -0.6% | +16.1% |
| QTRX | SELL · 10b5-1 | 2020-06-08 | 2020-06-10 | $25.64 | $82K | +5.1% | +6.2% | +19.6% |
| QTRX | SELL · 10b5-1 | 2020-05-27 | 2020-05-29 | $26.27 | $84K | -3.9% | -2.2% | +27.4% |
| QTRX | SELL · 10b5-1 | 2020-05-12 | 2020-05-14 | $27.23 | $87K | +7.2% | +3.8% | +36.8% |
| QTRX | SELL | 2020-04-27 | 2020-04-29 | $26.32 | $211K | +11.9% | +11.3% | +13.1% |
| QTRX | SELL · 10b5-1 | 2020-04-14 | 2020-04-16 | $21.07 | $164K | +9.9% | +9.7% | +22.8% |
| QTRX | SELL | 2020-04-06 | 2020-04-08 | $20.34 | $177K | +0.7% | +14.0% | +16.7% |
| QTRX | SELL | 2020-04-02 | 2020-04-03 | $20.22 | $281K | +14.6% | +35.3% | +37.3% |
| QTRX | SELL | 2020-03-04 | 2020-03-06 | $22.99 | $179K | -43.9% | +6.0% | +32.4% |
Grouped by shared companies and similar filing behaviour. This is a similarity measure, not a ranking or a performance signal.
| MIL |
| 30,234 |
| — |
| COV | 6,235 | — |
| Total | $12.4M |
Shares reported on the most recent Form 4, priced at the 2026-09-23 close. 2 holdings could not be priced and are excluded from the total.