[Form 4] NewAmsterdam Pharma Company N.V. Warrant Insider Trading Activity

Rhea-AI Filing Summary

Insider sales totaling 100,000 ordinary shares were reported by Johannes J.P. Kastelein, Chief Scientific Officer and Director of NewAmsterdam Pharma Co N.V. (NAMSW). The Form 4 shows three dispositions: 50,000 shares sold on 08/21/2025 at a weighted average price of $24.29, 42,342 shares sold on 08/22/2025 at a weighted average price of $25.08, and 7,658 shares sold on 08/22/2025 at a weighted average price of $25.49. After these transactions, the reporting person beneficially owns 69,302 ordinary shares indirectly through Futurum B.V., over which he reports sole voting and investment control. The filing includes weighted-average price ranges for each sale batch and is signed by a power of attorney on 08/25/2025.

Positive

• None.

Negative

• Insider dispositions totaling 100,000 shares reduced the reporting person's indirect beneficial ownership to 69,302 shares.
• Sales occurred over two consecutive days (08/21/2025–08/22/2025), indicating a material reduction in holdings during that period.

Insights

Financial Analyst

TL;DR: A director/officer reported routine sales totaling 100,000 shares, reducing indirect ownership to 69,302 shares; transactions appear documented and disclosed properly.

The Form 4 discloses three separate sale transactions executed over two days with detailed weighted-average pricing ranges. The shares remain indirectly held through Futurum B.V., with the reporting person retaining sole voting and investment control. From a financial reporting perspective, the filing meets Section 16 disclosure requirements by listing transaction dates, codes, amounts, and post-transaction beneficial ownership. The magnitude of the sale (100,000 shares) and the resulting beneficial holding are clearly stated, allowing investors to quantify the change in insider exposure without additional inference.

Corporate Governance Expert

TL;DR: Insider sales were properly reported and indicated as indirect holdings via an entity controlled by the reporting person.

The filing identifies the reporting person as both a director and officer and specifies that the ordinary shares are held by Futurum B.V. for his benefit, with sole voting and investment control. The Form 4 includes explanations about weighted-average prices and an undertaking to provide detailed transaction breakdowns upon request, which supports transparency. The submission is signed by a power of attorney, meeting signature formalities. The filing does not include any additional governance actions or changes in control; it solely documents disposition activity.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Kastelein Johannes Jacob Pieter

(Last) (First) (Middle)

C/O NEWAMSTERDAM PHARMA COMPANY N.V.

GOOIMEER 2-35

(Street)

NAARDEN P7 1411 DC

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
NewAmsterdam Pharma Co N.V. [ NAMS ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

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

3. Date of Earliest Transaction (Month/Day/Year)
08/21/2025

4. 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 Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Ordinary Shares	08/21/2025		S		50,000	D	$24.29(1)	119,302	I	See footnote(2)
Ordinary Shares	08/22/2025		S		42,342	D	$25.08(3)	76,960	I	See footnote(2)
Ordinary Shares	08/22/2025		S		7,658	D	$25.49(4)	69,302	I	See footnote(2)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $23.73 per share to $24.57 per share. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold in each transaction.

2. The ordinary shares are held by Futurum B.V. ("Futurum") for the benefit of the Reporting Person. The Reporting Person exercises sole voting and investment control over the ordinary shares held by Futurum.

3. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $24.39 per share to $25.35 per share. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold in each transaction.

4. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $25.39 per share to $25.62 per share. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold in each transaction.

	/s/ Louise Kooij by Power of Attorney for Johannes Jacob Pieter Kastelein	08/25/2025
	** 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 4 (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.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What transactions did Johannes J.P. Kastelein report on Form 4 for NAMSW?

The Form 4 reports three sales totaling 100,000 ordinary shares: 50,000 on 08/21/2025 at a weighted average of $24.29, 42,342 on 08/22/2025 at $25.08, and 7,658 on 08/22/2025 at $25.49.

How many NAMSW shares does the reporting person own after these transactions?

After the reported dispositions, the reporting person beneficially owns 69,302 ordinary shares indirectly through Futurum B.V.

Are the shares held directly by the reporting person or through an entity?

The ordinary shares are held indirectly by Futurum B.V. for the benefit of the reporting person, who states sole voting and investment control.

Did the Form 4 provide pricing details for the sales?

Yes. Each sale lists a weighted-average price and a price range for the multiple transactions comprising each reported sale, with an undertaking to provide detailed per-transaction numbers on request.

Who signed the Form 4 and when?

The Form 4 was signed by Louise Kooij by power of attorney for Johannes J.P. Kastelein on 08/25/2025.