William P Donnelly bought $286k of QTRX
Executive Chair at Quanterix Corp. 99,400 shares at an average of $2.88, traded Aug 12, 2026, filed Aug 14, 2026.
Score components
- +15RoleDirector
- +14Trade size$286k at market
- +8Relative to holdingsFirst purchase: no shares before this trade
- +8Price context64% below the 52-week high
- 0ClusterNo other insider buying within 14 days
- 0Repeat buyingFirst buy in 90 days
- 0Track recordToo few past buys to judge (0 with prices)
What happened after comparable buys
Same side and tier, against the S&P 500, at 1, 3 and 6 months. Shown to Pro users; the whole table is on the backtest page.
Price around the trade, and since
From a quarter before the trade to today. The arrow is the trade, the circle the day the filing reached EDGAR, which is the first day anyone outside could act; the dotted line is the S&P 500 rebased to that day's close.
Daily candles, adjusted for splits and dividends. Green arrows are insider buys, red are sells, sized by value; the dashed line is the close on the filing day, the dotted line SPY rebased to it.Charts by TradingView Lightweight Charts™
Rows in this filing
Every transaction in Form 4 0001207928-26-000008, as filed. Open on EDGAR
| Date | Transaction | Shares | Price | Value | Holdings after | Filed |
|---|---|---|---|---|---|---|
| Aug 12, 2026 | POpen-market purchase Common Stockindirect: See footnote | +27,155 | $2.75 | $75k | 27,155 | Aug 14, 2026 |
| Aug 13, 2026 | POpen-market purchase Common Stockindirect: See Footnote | +72,245 | $2.93 | $212k | 99,400 | Aug 14, 2026 |
Related signals
Other insiders at Quanterix Corp and this insider’s other filings.
| Score | Company | Insider | Value | Holdings | Filed |
|---|---|---|---|---|---|
| 41Moderate | QTRXbuy Quanterix Corp | Benjamin Meadows Chief Commercial Officer | $9,695 3,500 shares | - | |
| 22Weak | QTRXbuy Quanterix Corp | Vandana Sriram Chief Financial Officer | $20k 4,150 shares | +5% | |
| 63Notable | Quanterix Corp | David R Walt director | $985k 160,000 shares | +9% | |
| 56Moderate | Quanterix Corp | Masoud Toloue President & CEO | $249k 45,900 shares | +10% | |
| 58Moderate | Quanterix Corp | William P Donnelly Executive Chair | $506k 93,113 shares | +203% | |
| 58Moderate | Quanterix Corp | David R Walt director | $1.1M 210,000 shares | +14% | |
| 51Moderate | Quanterix Corp | David R Walt director | $625k 47,000 shares | +3% | |
| 66Notable | Quanterix Corp | Masoud Toloue President & CEO | $207k 19,000 shares | +6% | |
| 0Weak | Quanterix Corp | Laurie J Olson director | $25k 1,500 shares | -10% | |
| 0Weak | Quanterix Corp | Laurie J Olson director | $24k 1,000 shares | -6% |
Not investment advice. Scores and forward returns are decision support built from public SEC filings and past prices; they describe what happened after comparable filings, not what will happen after this one. Do your own research and size your risk.