Bybee Clinton Form 3 Quanterix / CLINTON BYBEE ownership change

SEC Form 3

FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person^*

ARCH VENTURE FUND VI LP

(Last) (First) (Middle)

8755 WEST HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
12/06/2017

3. Issuer Name and Ticker or Trading Symbol
Quanterix Corp [ QTRX ]

4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

Director	X	10% Owner
Officer (give title below)		Other (specify below)

5. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

	Form filed by One Reporting Person
X	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Series A-1 Preferred Stock	(1)	(2)	Common Stock	398,257	(3)	D(4)
Series A-2 Preferred Stock	(1)	(2)	Common Stock	1,045,426	(3)	D(4)
Series B Preferred Stock	(1)	(2)	Common Stock	477,042	(3)	D(4)
Series C Preferred Stock	(1)	(2)	Common Stock	109,769	(3)	D(4)
Series D Preferred Stock	(1)	(2)	Common Stock	381,507	(3)	D(4)
Series D Preferred Stock	(1)	(2)	Common Stock	1,271,684	(3)	D(5)

1. Name and Address of Reporting Person^*

ARCH VENTURE FUND VI LP

(Last) (First) (Middle)

8755 WEST HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

ARCH Venture Fund VIII Overage, L.P.

(Last) (First) (Middle)

8755 WEST HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

ARCH VENTURE PARTNERS VI LP

(Last) (First) (Middle)

8755 WEST HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

ARCH VENTURE PARTNERS VI LLC

(Last) (First) (Middle)

8755 WEST HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

ARCH Venture Partners VIII, LLC

(Last) (First) (Middle)

8755 WEST HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

BYBEE CLINTON

(Last) (First) (Middle)

8755 WEST HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

NELSEN ROBERT

(Last) (First) (Middle)

8755 WEST HIGGINS ROAD, SUITE 1025

(Street)

CHICAGO IL 60631

(City) (State) (Zip)

Explanation of Responses:

1. 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.

2. Not applicable.

3. 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.

4. The shares are held of record by ARCH Venture Fund VI, L.P. ("ARCH Fund VI"). The sole general partner of ARCH Fund VI is ARCH Venture Partners VI, L.P. ("ARCH Partners VI"), which may be deemed to beneficially own the shares held by ARCH Fund VI. The sole general partner of ARCH Partners VI is ARCH Venture Partners VI, LLC ("ARCH VI LLC"), which may be deemed to beneficially own the shares held by ARCH Fund VI. ARCH Partners VI and ARCH VI LLC disclaim beneficial ownership of such shares, except to the extent of any pecuniary interest therein. As managing directors of ARCH VI LLC, Clinton Bybee and Robert Nelsen may be deemed to beneficially own the shares held by ARCH Fund VI. Messrs. Bybee and Nelsen disclaim beneficial ownership of such shares, except to the extent of any pecuniary interest therein.

5. The shares are held of record by ARCH Venture Fund VIII Overage, L.P. ("ARCH Fund Overage"). The sole general partner of ARCH Fund Overage is ARCH Venture Partners VIII, LLC ("ARCH VIII LLC"), which may be deemed to beneficially own the shares held by ARCH Fund Overage. ARCH VIII LLC disclaims beneficial ownership of such shares, except to the extent of any pecuniary interest therein. As managing directors of ARCH VIII LLC, Clinton Bybee and Robert Nelsen may be deemed to beneficially own the shares held by ARCH Fund Overage. Messrs. Bybee and Nelsen disclaim beneficial ownership of such shares, except to the extent of any pecuniary interest therein.

	/s/ Mark McDonnell, as Attorney-in-Fact for ARCH Venture Fund VI, L.P.	12/06/2017
	/s/ Mark McDonnell, as Attorney-in-Fact for ARCH Venture Fund VIII Overage, L.P.	12/06/2017
	/s/ Mark McDonnell, as Attorney-in-Fact for ARCH Venture Partners VI, L.P.	12/06/2017
	/s/ Mark McDonnell, as Attorney-in-Fact for ARCH Venture Partners VI, LLC	12/06/2017
	/s/ Mark McDonnell, as Attorney-in-Fact for ARCH Venture Partners VIII, LLC	12/06/2017
	/s/ Mark McDonnell, as Attorney-in-Fact for Clinton Bybee	12/06/2017
	/s/ Mark McDonnell, as Attorney-in-Fact for Robert Nelsen	12/06/2017
	** Signature of Reporting Person	Date
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