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CUSIP No.   90184D100

13G

Page 5 of 15 Pages

 

ARCH Venture Fund VII, L.P. ("ARCH Venture Fund VII"); ARCH Venture Fund VIII Overage, L.P. ("AVF VIII Overage LP"); ARCH Venture Partners VII, L.P. ("AVP VII LP"); ARCH Venture Partners VII, LLC ("AVP VII 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".

 

Common stock, par value $0.00001 per share.

 

ARCH Venture Fund VII is the record owner of 2,407,422 shares of Common Stock (the "ARCH VII Shares") as of December 31, 2018.  AVP VII LP, as the sole general partner of ARCH Venture Fund VII, may be deemed to beneficially own the ARCH VII Shares.  AVP VII LLC, as the sole general partner of AVP VII LP, may be deemed to beneficially own the Record Shares.  AVF VIII Overage LP is the record owner of 954,146 shares of Common Stock (the "Overage Shares"; combined with ARCH VIII Shares, the "Record Shares") as of December 31, 2018.  AVP VIII LLC, as the sole general partner of AVF VIII Overage LP, may be deemed to beneficially own the Overage Shares.  As managing directors of AVP VII 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.

 

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See line 5 of the cover sheets.

 

See line 6 of the cover sheets.

 

    See line 7 of the cover sheets.

 

    See line 8 of the cover sheets.

 

	*
	Robert Nelsen

 

	*
	Clinton Bybee

 

 

	By:                    *
	Keith Crandell
	Managing Director

 

 

 

	*
	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, member, 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. This Power of Attorney shall remain in full force and effect with respect to each undersigned person unless and until six months after such person is both no longer a Managing Director of ARCH Venture Partners and no longer serving on the board of directors of any portfolio company of any ARCH Venture Partners fund.

 

 

	By:   /s/ Keith Crandell
	Managing Director