LYTIR

Company · QTRX

Quanterix Corporation

Name as listed on its exchange; filed with the SEC as Quanterix Corp.

Nasdaq's symbol directory lists QTRX on Nasdaq as “Quanterix Corporation - Common Stock”.

In the 12 months to Nov 8, 2026: insiders bought on 2 occasions ($286K); 2 filings by holders of 5% or more.

All insider filings at the SEC

Insider trades · SEC Form 4

Those inside the hall

Open-market purchases and sales only. Legs one person filed for one day are combined.

Who traded

  1. DONNELLY WILLIAM P bought on 2 days latest Aug 13, 2026 bought $286K
Every trade (2)
  1. BUYDONNELLY WILLIAM P bought Aug 13, 2026 72,245 shares filing $212K
  2. BUYDONNELLY WILLIAM P bought Aug 12, 2026 27,155 shares filing $75K

Large holders · SEC Schedules 13D and 13G

Five percent and over

Anyone who comes to hold more than 5% of a company's voting shares must tell the SEC. A Schedule 13D is filed by a holder who may seek to influence the company; a 13G by one who states it is a passive investor. An amendment updates an earlier filing, and a stake reported as 0% means the holder says it has sold all, or nearly all, of its shares. Every recent 13D and 13G

  1. Portolan Capital Management, LLC filed Aug 14, 2026 Schedule 13G/A passive filing 4.02%
  2. First Eagle Investment Management, LLC filed Aug 6, 2026 Schedule 13G passive 2,753,165 shares filing 5.8%

Sources: SEC EDGAR (Forms 4 and 144) and STOCK Act periodic transaction reports. Filings can be late, amended or wrong at the source; see methodology.