Metsera (MTSR) Form 3 Metsera / Steven Marso 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^*

Marso Steven

(Last) (First) (Middle)

C/O METSERA, INC. 3 WORLD TRADE CENTER

175 GREENWICH STREET

(Street)

NEW YORK NY 10007

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

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

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

X	Form filed by One Reporting Person
	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
Stock Option (Right to Buy)	(1)	05/25/2033	Common Stock	829,885	0.26	D
Stock Option (Right to Buy)	(2)	05/25/2033	Common Stock	21,279	0.26	D

Explanation of Responses:

1. The options vested and became exercisable as to 25% of the shares underlying the option on each of May 26, 2023 and May 26, 2024 and the remaining shares underlying the option shall vest and become exercisable as to 25% on each of May 26, 2025 and May 26, 2026.

2. The options are fully vested.

Remarks:

Exhibit 24.1 - Power of Attorney

	/s/ Christopher J. Visioli, Attorney-in-fact for Steven Marso	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).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
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