Through the 90-day period concluding February 19, 2026, Quanterix's top three insider stakeholders include Director David R Walt (1.87Mn shares), Executive Chairman E Kevin Hrusovsky (910.25K shares), President & Ceo Masoud Toloue (507.31K shares).
| Holder | Position | Shares | Report Date |
|---|---|---|---|
| David R Walt | 1,872,890 | 06 Jan, 2026 | |
| E Kevin Hrusovsky | Executive Chairman | 910,249 | 06 Jul, 2022 |
| Masoud Toloue | President & Ceo | 507,310 | 20 Jan, 2026 |
| Paul M Meister | 313,253 | 15 Jan, 2026 | |
| Martin D Madaus | 291,541 | 06 Jan, 2025 | |
| William P Donnelly | Executive Chair | 150,751 | 06 Jan, 2026 |
| Keith Crandell | 131,236 | 04 Apr, 2023 | |
| Michael A Doyle | Cfo And Treasurer | 88,332 | 02 Oct, 2023 |
| Vandana Sriram | Chief Financial Officer | 81,618 | 06 Feb, 2026 |
| Alan Bruce Sachs | 70,099 | 06 Jan, 2026 | |
| Malcolm Garret Hampton | 70,099 | 06 Jan, 2026 | |
| Sarah E. Hlavinka | 60,070 | 03 Jul, 2025 | |
| Karen Flynn | 57,212 | 06 Jan, 2026 | |
| Scott Mendel | 56,053 | 06 Jan, 2026 | |
| Goldman Myla Lai | 54,804 | 06 Jan, 2026 | |
| David C. Duffy | Svp R&D And Cto | 54,730 | 28 Mar, 2022 |
| Ivana Magovcevic-Liebisch | 43,607 | 15 Jan, 2026 | |
| Jeffrey Thomas Elliott | 42,792 | 14 Jan, 2026 | |
| John J Fry | General Counsel & Secretary | 37,671 | 03 Aug, 2022 |
| Dawn Mattoon | Sr. Vp And Diagnostics | 36,876 | 05 Apr, 2022 |
| Amol Chaubal | Chief Financial Officer | 30,222 | 05 May, 2021 |
| Mark T. Roskey | Svp And Strategic Partnerships | 22,325 | 05 Apr, 2022 |
| Brian J Blaser | 19,049 | 04 Jan, 2024 | |
| Laurie J Olson | 13,738 | 14 May, 2024 | |
| Shawn Stetson | Interim Cfo And Treasurer | 4,712 | 13 May, 2021 |
* Please note that the shares above only reflect shares from the fund portfolio and the institutional portfolio. Shares from the personal portfolio are excluded from this Institutional Ownership Page. See these insiders' latest transactions here on Insider Page.
| Transaction Date | Insider Name | Security Class | Transaction Type | Shares Traded | Price | Shares Remaining | Ownership | Code |
|---|---|---|---|---|---|---|---|---|
| 04 Feb, 2026 | Vandana Sriram | Common Stock | D | 4,395 | $0.00 | 81,618 | D | F |
| 15 Jan, 2026 | Masoud Toloue | Common Stock | D | 1,817 | $7.95 | 507,310 | D | F |
| 15 Jan, 2026 | Vandana Sriram | Common Stock | D | 274 | $7.95 | 86,013 | D | F |
| 02 Jan, 2026 | Paul M Meister | Common Stock | A | 3,974 | $0.00 | 313,253 | D | A |
| 02 Jan, 2026 | Goldman Myla Lai | Common Stock | A | 1,944 | $0.00 | 54,804 | D | A |
| 02 Jan, 2026 | Goldman Myla Lai | Common Stock | A | 23,372 | $0.00 | 52,860 | D | A |
| 02 Jan, 2026 | David R Walt | Common Stock | A | 1,215 | $0.00 | 1,872,890 | D | A |
| 02 Jan, 2026 | William P Donnelly | Common Stock | A | 2,377 | $0.00 | 150,751 | D | A |
| 02 Jan, 2026 | Ivana Magovcevic-Liebisch | Common Stock | A | 23,372 | $0.00 | 43,607 | D | A |
| 02 Jan, 2026 | Scott Mendel | Common Stock | A | 1,944 | $0.00 | 56,053 | D | A |
| 02 Jan, 2026 | Scott Mendel | Common Stock | A | 23,372 | $0.00 | 54,109 | D | A |
| 02 Jan, 2026 | Karen Flynn | Common Stock | A | 23,372 | $0.00 | 57,212 | D | A |
| 02 Jan, 2026 | Jeffrey Thomas Elliott | Common Stock | A | 23,372 | $0.00 | 42,792 | D | A |
| 02 Jan, 2026 | Malcolm Garret Hampton | Common Stock | A | 23,372 | $0.00 | 70,099 | D | A |
| 02 Jan, 2026 | Alan Bruce Sachs | Common Stock | A | 23,372 | $0.00 | 70,099 | D | A |
| 31 Dec, 2025 | Masoud Toloue | Common Stock | D | 258 | $6.36 | 508,446 | D | F |
| 15 Dec, 2025 | Masoud Toloue | Common Stock | D | 1,242 | $7.41 | 508,704 | D | F |
| 15 Dec, 2025 | Vandana Sriram | Common Stock | D | 229 | $7.41 | 85,977 | D | F |
| 30 Nov, 2025 | Masoud Toloue | Common Stock | D | 254 | $7.26 | 509,946 | D | F |
| 20 Nov, 2025 | Malcolm Garret Hampton | Common Stock | A | 46,727 | - | 46,727 | D | A |