Quanterix Corp — Director's Dealing 2017

Dec 7, 2017

SEC Form 3 — Initial Statement of Beneficial Ownership

Issuer: Quanterix Corp (QTRX)
CIK: 0001503274
Period of Report: 2017-12-06

Reporting Person: Flagship Ventures Fund 2004 L P (10% Owner)
Reporting Person: Flagship Ventures General Partner LLC (10% Owner)
Reporting Person: AFEYAN NOUBAR (10% Owner)
Reporting Person: KANIA EDWIN M JR (10% Owner)

Holdings (Derivative)

Security	Exercise Price	Expiration	Underlying	Shares	Ownership
Series A-1 Preferred Stock	$		Common Stock (398257)		Direct
Series A-2 Preferred Stock	$		Common Stock (1045426)		Direct
Series B Preferred Stock	$		Common Stock (477042)		Direct
Series C Preferred Stock	$		Common Stock (109770)		Direct

Footnotes

F1: These shares are convertible into the Issuer's common stock in accordance with the Issuer's Restated Certificate of Incorporation, as amended, at any time after the issuance of such shares, at the holder's election.

F2: Not applicable.

F3: The shares of preferred stock will convert into common stock immediately prior to the closing of the Issuer's initial public offering using a calculation defined in the Issuer's Restated Certificate of Incorporation, as amended, based on the initial purchase price and the conversion rate in effect at the time of conversion. The shares of preferred stock will convert on a 1-for-3.214 basis and such conversion rate is reflected in the amount of common stock underlying the security.

F4: Held by Flagship Ventures Fund 2004, L.P. Flagship Ventures General Partner LLC (the "GP") is the General Partner of Flagship Ventures Fund 2004, L.P. Noubar B. Afeyan, Ph.D. and Edwin M. Kania, Jr. are the Managers of the GP. The GP, Dr. Afeyan and Mr. Kania may be deemed to possess voting and investment control over all shares held by Flagship Ventures Fund 2004, L.P. Each of the reporting persons disclaims beneficial ownership of the shares except to the extent of his or its pecuniary interest therein.