SEC FORM 3 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 Partners XII, LLC

(Last) (First) (Middle)
8755 W. HIGGINS ROAD, SUITE 1025

(Street)
CHICAGO IL 60631

(City) (State) (Zip)
2. Date of Event Requiring Statement (Month/Day/Year)
01/30/2025
3. Issuer Name and Ticker or Trading Symbol
Metsera, Inc. [ MTSR ]
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)
Common Stock 1,063,955 I See Footnote(1)
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 Seed Preferred Stock (2) (2) Common Stock 8,483,268 (2) I See Footnote(1)
Series A Convertible Preferred Stock (2) (2) Common Stock 6,383,730 (2) I See Footnote(1)
Series B Convertible Preferred Stock (2) (2) Common Stock 1,139,951 (2) I See Footnote(1)
Series A Convertible Preferred Stock (2) (2) Common Stock 6,383,731 (2) I See Footnote(3)(4)
Series B Convertible Preferred Stock (2) (2) Common Stock 1,139,951 (2) I See Footnote(3)(4)
1. Name and Address of Reporting Person*
ARCH Venture Partners XII, LLC

(Last) (First) (Middle)
8755 W. HIGGINS ROAD, SUITE 1025

(Street)
CHICAGO IL 60631

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer
Director X 10% Owner
Officer (give title below) Other (specify below)
1. Name and Address of Reporting Person*
ARCH Venture Fund XII, L.P.

(Last) (First) (Middle)
8755 W. HIGGINS ROAD, SUITE 1025

(Street)
CHICAGO IL 60631

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer
Director X 10% Owner
Officer (give title below) Other (specify below)
1. Name and Address of Reporting Person*
ARCH Venture Partners XII, L.P.

(Last) (First) (Middle)
8755 W. HIGGINS ROAD, SUITE 1025

(Street)
CHICAGO IL 60631

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer
Director X 10% Owner
Officer (give title below) Other (specify below)
1. Name and Address of Reporting Person*
ARCH Venture Fund XIII, L.P.

(Last) (First) (Middle)
8755 W. HIGGINS ROAD, SUITE 1025

(Street)
CHICAGO IL 60631

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer
Director X 10% Owner
Officer (give title below) Other (specify below)
1. Name and Address of Reporting Person*
ARCH Venture Partners XIII, L.P.

(Last) (First) (Middle)
8755 W. HIGGINS ROAD, SUITE 1025

(Street)
CHICAGO IL 60631

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer
Director X 10% Owner
Officer (give title below) Other (specify below)
1. Name and Address of Reporting Person*
ARCH Venture Partners XIII, LLC

(Last) (First) (Middle)
8755 W. HIGGINS ROAD, SUITE 1025

(Street)
CHICAGO IL 60631

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer
Director X 10% Owner
Officer (give title below) Other (specify below)
1. Name and Address of Reporting Person*
CRANDELL KEITH

(Last) (First) (Middle)
8755 W. HIGGINS ROAD, SUITE 1025

(Street)
CHICAGO IL 60631

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer
Director X 10% Owner
Officer (give title below) Other (specify below)
1. Name and Address of Reporting Person*
GILLIS STEVEN

(Last) (First) (Middle)
8755 W. HIGGINS ROAD, SUITE 1025

(Street)
CHICAGO IL 60631

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer
Director X 10% Owner
Officer (give title below) Other (specify below)
1. Name and Address of Reporting Person*
NELSEN ROBERT

(Last) (First) (Middle)
8755 W. HIGGINS ROAD, SUITE 1025

(Street)
CHICAGO IL 60631

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer
Director X 10% Owner
Officer (give title below) Other (specify below)
Explanation of Responses:
1. Represents shares held directly by ARCH Venture Fund XII, L.P ("ARCH Venture Fund XII"). ARCH Venture Partners XII, L.P. ("AVP XII LP"), as the sole general partner of ARCH Venture Fund XII, may be deemed to beneficially own the shares held by ARCH Venture Fund XII. ARCH Venture Partners XII, LLC ("AVP XII LLC"), as the sole general partner of AVP XII LP, may be deemed to beneficially own the shares held by ARCH Venture Fund XII. AVP XII LP and AVP XII LLC disclaim beneficial ownership except to the extent of any pecuniary interest therein. As members of the investment committee of AVP XII LLC, each of Kristina M. Burow, Keith Crandell, Steven Gillis and Robert Nelsen (the "AVP XII Committee Members") may also be deemed to share the power to direct the disposition and vote of the ARCH Venture Fund XII shares. Each AVP XII Committee Member disclaims beneficial ownership except to the extent of any pecuniary interest therein.
2. The shares of Issuer's preferred stock have no expiration date and are convertible at the holder's election into Issuer's common stock at a conversion ratio of 1-for-2.349723. The preferred stock will automatically convert into shares of the Issuer's common stock, for no additional consideration, upon the closing of the Issuer's initial public offering.
3. Represents shares held directly by ARCH Venture Fund XIII, L.P.("ARCH Venture Fund XIII"). ARCH Venture Partners XIII, L.P. ("AVP XIII LP"), as the sole general partner of ARCH Venture Fund XIII, may be deemed to beneficially own the shares held by ARCH Venture Fund XIII. ARCH Venture Partners XIII, LLC ("AVP XIII LLC"), as the sole general partner of AVP XIII LP, may be deemed to beneficially own the shares held by ARCH Venture Fund XIII. AVP XIII LP and AVP XIII LLC disclaim beneficial ownership except to the extent of any pecuniary interest therein. As members of the investment committee of AVP XIII LLC, each of Paul L. Berns, Kristina M. Burow, Keith Crandell and Robert Nelsen (the "AVP XIII Committee Members") may also be deemed to share the power to direct the disposition and vote of the ARCH Venture Fund XIII shares. Each AVP XIII Committee Member disclaims beneficial ownership except to the extent of any pecuniary interest therein.
4. (Continued from footnote 3) Each of Kristina Burrow and Paul Berns has filed a separate Form 3.
Remarks:
Exhibit 24.1 - Power of Attorney
ARCH Venture Fund XII, L.P. By: ARCH Venture Partners XII, L.P., its General Partner By: ARCH Venture Partners XII, LLC, its General Partner By: /s/ Mark McDonnell, as Attorney-in-Fact 01/30/2025
ARCH Venture Partners XII, L.P. By: ARCH Venture Partners XII, LLC, its General Partner By: /s/ Mark McDonnell, as Attorney-in-Fact 01/30/2025
ARCH Venture Partners XII, LLC By: /s/ Mark McDonnell, as Attorney-in-Fact 01/30/2025
ARCH Venture Fund XIII, L.P. By: ARCH Venture Partners XIII, L.P., its General Partner By: ARCH Venture Partners XIII, LLC, its General Partner By: /s/ Mark McDonnell, as Attorney-in-Fact 01/30/2025
ARCH Venture Partners XIII, L.P. By: ARCH Venture Partners XIII, LLC, its General Partner By: /s/ Mark McDonnell, as Attorney-in-Fact 01/30/2025
ARCH Venture Partners XIII, LLC By: /s/ Mark McDonnell, as Attorney-in-Fact 01/30/2025
/s/ Keith Crandell, By: Mark McDonnell, attorney-in-fact 01/30/2025
/s/ Steven Gillis, By: Mark McDonnell, attorney-in-fact 01/30/2025
/s/ Robert Nelsen, By: Mark McDonnell, attorney-in-fact 01/30/2025
** Signature of Reporting Person Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 5 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
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