[Form 4] Y-mAbs Therapeutics, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Form 4 filing for Y-mAbs Therapeutics (YMAB) discloses that director Laura Hamill received new equity awards on 30 June 2025.

• Restricted Stock Units: 25,080 RSUs granted at no cost. The award vests in full on the earlier of 12 months after grant or immediately before the 2026 annual shareholder meeting, subject to continued service.
• Stock Options: 33,450 options with a US$4.51 exercise price, expiring 30 June 2035. Vest in equal monthly instalments over one year and become exercisable upon vesting.
• Post-transaction ownership: Hamill now directly holds 30,905 YMAB common shares and 33,450 vested/unvested options.

The transactions reflect routine director compensation under the 2018 Equity Incentive Plan and do not involve open-market purchases or sales.

Insights

Securities Analyst

TL;DR – Routine equity grants; negligible impact on YMAB valuation.

The filing records standard annual equity compensation for a non-executive director. No shares were bought or sold in the market; therefore, no immediate cash flow effect on the company and no strong signalling value regarding insider sentiment. Grants align the director’s incentives with shareholders but are immaterial relative to YMAB’s ~41 million shares outstanding. Overall investor impact is neutral.

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

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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^*

HEALY JAMES

(Last) (First) (Middle)

C/O SOFINNOVA INVESTMENTS INC.

3000 SAND HILL ROAD, BLDG. 4, SUITE 250

(Street)

MENLO PARK CA 94025

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Y-mAbs Therapeutics, Inc. [ YMAB ]

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

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

3. Date of Earliest Transaction (Month/Day/Year)
06/30/2025

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
Common Stock	06/30/2025		A		25,080(1)	A	$0	56,683	D
Common Stock								2,194,278	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
Employee Stock Option (right to buy)(3)	$4.51	06/30/2025		A		33,450		(4)	06/30/2035	Common Stock	33,450	$0	33,450	D

Explanation of Responses:

1. Represents restricted stock units ("RSUs") granted to the Reporting Person pursuant to the Issuer's 2018 Equity Incentive Plan. Each RSU represents a contingent right to receive one share of the Issuer's common stock on the vesting date of the RSUs. The RSUs vest in full on the earlier of the first anniversary of the date of grant or the date immediately preceding the date of the Issuer's annual meeting of stockholders held in 2026, subject to the Reporting Person's continued service to the Issuer on the vesting date.

2. The Reporting Person is one of the managing members of the general partner of Sofinnova Management X-A, L.L.C., the general partner of Sofinnova Management X, L.P., the general partner of Sofinnova Venture Partners X, L.P., which directly holds the reported securities, and, as such, may be deemed to share voting and investment power over such shares. The Reporting Person disclaims beneficial ownership of the reported securities, except to the extent of his proportionate pecuniary interest in Sofinnova Ventures Partners X, L.P.

3. Stock options granted to the Reporting Person pursuant to the Issuer's 2018 Equity Incentive Plan.

4. The stock options vest in equal monthly installments until the first anniversary of the date of grant, subject to the Reporting Person's continued service to the Issuer on each vesting date, and are exercisable immediately upon vesting.

	/s/ John LaRocca, Attorney-in-Fact	07/02/2025
	** 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 equity awards did YMAB director Laura Hamill receive on 30 June 2025?

She was granted 25,080 RSUs and 33,450 stock options with a US$4.51 exercise price.

When do the 25,080 RSUs granted to Laura Hamill vest?

They vest in full on the earlier of one year after grant or immediately before YMAB’s 2026 annual meeting, subject to continued service.

What is the exercise window for the 33,450 options issued to Laura Hamill?

The options vest monthly over one year and are exercisable upon vesting, expiring on 30 June 2035.

How many YMAB common shares does Laura Hamill own after the reported transactions?

She directly owns 30,905 shares of YMAB common stock.

Did the Form 4 indicate any open-market purchase or sale of YMAB shares?

No. The filing only shows equity awards; there were no open-market transactions.