Kristina M. Burow. - 03 Feb 2025 Form 4 Insider Report for Metsera, Inc. (MTSR)

Role: Director, 10%+ Owner
Signature: /s/ Christopher J. Visioli, Attorney-in-fact for Kristina M. Burow
Issuer symbol: MTSR
Transactions as of: 03 Feb 2025
Net transactions value: +$39,999,996
Form type: 4
Filing time: 03 Feb 2025, 19:15:35 UTC
Previous filing: 30 Jan 2025
Next filing: 18 Feb 2025
SEC: View on sec.gov

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	MTSR	Common Stock	Conversion of derivative security		+16,006,949	+1504%		17,070,904	03 Feb 2025	See footnote	F1, F2
transaction	MTSR	Common Stock	Purchase	$25,780,032	+1,432,224	+8.4%	$18.00	18,503,128	03 Feb 2025	See footnote	F2
transaction	MTSR	Common Stock	Conversion of derivative security		+7,523,682			7,523,682	03 Feb 2025	See footnote	F1, F3
transaction	MTSR	Common Stock	Purchase	$14,219,964	+789,998	+11%	$18.00	8,313,680	03 Feb 2025	See footnote	F3

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	MTSR	Series Seed Preferred Stock	Conversion of derivative security		-19,933,333	-100%		0	03 Feb 2025	Common Stock	8,483,268		See footnote	F1, F2
transaction	MTSR	Series A Convertible Preferred Stock	Conversion of derivative security		-15,000,000	-100%		0	03 Feb 2025	Common Stock	6,383,730		See footnote	F1, F2
transaction	MTSR	Series B Convertible Preferred Stock	Conversion of derivative security		-2,678,571	-100%		0	03 Feb 2025	Common Stock	1,139,951		See footnote	F1, F2
transaction	MTSR	Series A Convertible Preferred Stock	Conversion of derivative security		-15,000,000	-100%		0	03 Feb 2025	Common Stock	6,383,731		See footnote	F1, F3
transaction	MTSR	Series B Convertible Preferred Stock	Conversion of derivative security		-2,678,571	-100%		0	03 Feb 2025	Common Stock	1,139,951		See footnote	F1, F3

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	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 automatically converted into shares of the Issuer's common stock, for no additional consideration, upon the closing of the Issuer's initial public offering.
F2	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.
F3	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, Steven Gillis 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.