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Quanterix Corporation (the "Issuer").

 

113 Hartwell Avenue, Lexington, MA  02421

 

ARCH Venture Fund VI, L.P. ("ARCH Venture Fund VI"); ARCH Venture Fund VIII Overage, L.P. ("AVF VIII Overage"); ARCH Venture Partners VI, L.P. ("AVP VI LP"); ARCH Venture Partners VI, LLC ("AVP VI LLC"); ARCH Venture Partners VIII, LLC ("AVP VIII LLC") (collectively, the "Reporting Entities" and individually, each a "Reporting Entity"); and Keith Crandell ("Crandell"), Robert Nelsen ("Nelsen") and Clinton Bybee ("Bybee") (collectively, the "Managing Directors" and individually, each a "Managing Director").  The Reporting Entities and the Managing Directors collectively are referred to as the "Reporting Persons".

 

8755 W. Higgins Avenue, Suite 1025, Chicago, IL 60631.

 

ARCH Venture Fund VI, AVF VIII Overage and AVP VI LP are limited partnerships organized under the laws of the State of Delaware. AVP VI LLC and AVP VIII LLC are limited liability companies organized under the laws of the State of Delaware.  Each Managing Director is a US citizen.

 

 

74766Q101.

 

Not Applicable.

 

(a)

Amount beneficially owned:

 

ARCH Venture Fund VI is the record owner of 2,412,001 shares of Common Stock (the "ARCH VI Shares") and AVF VIII Overage is the record holder of 1,537,684 share of Common Stock (the "ARCH Overage Shares"; combined with ARCH VI Shares, the "Record Shares") as of December 31, 2017.  AVP VI LP, as the sole general partner of ARCH Venture Fund VI, may be deemed to beneficially own the AVF VI Shares  AVP VI LLC, as the sole general partner of AVP VI LP, may be deemed to beneficially own the AVF VI Shares.  AVP VIII LLC, as the sole general partner of AVF VIII Overage, may be deemed beneficially own the ARCH VIII Overage Shares.  As managing directors of AVP VI LLC and AVP VIII LLC, each Managing Director may also be deemed to share the power to direct the disposition and vote of the Record Shares.

(b)

Percent of class:

 

In the aggregate, the Reporting Persons beneficially own approximately 18.1% of the outstanding shares of common stock of the Issuer, based upon 21,820,840 shares of common stock outstanding as of December 11, 2017, which combines 21,179,560 Common Stock outstanding as reported on the Issuer's 424B4 as filed with the Securities and Exchange Commission on December 7, 2017, plus 641,280 shares issued (underwriter's allocation) as reported on the Issuer's 8-K as filed with the Securities and Exchange Commission on December 15, 2017.

CUSIP No.   74766Q101

13G

Page 11 of 15 Pages

 

 

 

(c)

Number of shares as to which such person has:

 

(i)    Sole power to vote or to direct the vote:

(ii)   Shared power to vote or to direct the vote:

(iii)  Sole power to dispose or to direct the disposition:

(iv)  Shared power to dispose or to direct the disposition:

Each Reporting Person disclaims beneficial ownership of such shares of Common Stock except for the shares, if any, such Reporting Person holds of record.

Not Applicable.

 

Not Applicable.

 

Item 10.

Certification

 

 

	By:                    *
	Keith Crandell
	Managing Director

 

 

 

 

 

	ARCH VENTURE PARTNERS VI, L.P.
	By:   ARCH Venture Partners VI, LLC
	its General Partner

 

	*
	Keith Crandell

 

KNOW ALL MEN BY THESE PRESENTS, that each person whose signature appears below hereby constitutes and appoints Mark McDonnell his true and lawful attorney-in-fact, with full power of substitution, to sign any and all instruments, certificates and documents that may be necessary, desirable or appropriate to be executed on behalf of himself as an individual or in his capacity as a direct or indirect general partner, director, officer or manager of any partnership, corporation or limited liability company, pursuant to section 13 or 16 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), and any and all regulations promulgated thereunder, and to file the same, with all exhibits thereto, and any other documents in connection therewith, with the Securities and Exchange Commission, and with any other entity when and if such is mandated by the Exchange Act or by the Financial Industry Regulatory Authority, granting unto said attorney-in-fact full power and authority to do and perform each and every act and thing necessary, desirable or appropriate, fully to all intents and purposes as he might or could do in person, thereby ratifying and confirming all that said attorney-in-fact, or his substitutes, may lawfully do or cause to be done by virtue hereof.

 

IN WITNESS WHEREOF, this Power of Attorney has been signed as of the 10^th day of November, 2010.

 

 

 

 

	ARCH VENTURE PARTNERS VI, L.P.
	By:   ARCH Venture Partners VI, LLC
	its General Partner

 

	/s/ Keith Crandell
	Keith Crandell