Johan Wedell-Wedellsborg - 30 Jun 2025 Form 4 Insider Report for Y-mAbs Therapeutics, Inc. (YMAB)

Role: Director, 10%+ Owner
Signature: /s/ John LaRocca, Attorney-in-Fact
Issuer symbol: YMAB
Transactions as of: 30 Jun 2025
Net transactions value: $0
Form type: 4
Filing time: 02 Jul 2025, 16:20:21 UTC
Previous filing: 13 Jun 2024
Next filing: 18 Sep 2025
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Wedell-Wedellsborg Johan	Director, 10%+ Owner	C/O Y-MABS THERAPEUTICS, INC., 230 PARK AVENUE, SUITE 3350, NEW YORK	/s/ John LaRocca, Attorney-in-Fact	02 Jul 2025	0001753185

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	YMAB	Common Stock	Award	$0	+25,080	+431%	$0.000000	30,905	30 Jun 2025	Direct	F1
holding	YMAB	Common Stock						4,559,233	30 Jun 2025	By WG Biotech ApS	F2

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	YMAB	Employee Stock Option (right to buy)	Award	$0	+33,450		$0.000000	33,450	30 Jun 2025	Common Stock	33,450	$4.51	Direct	F3, F4

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

Explanation of Responses:

Id	Content
F1	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.
F2	Reporting Person is the majority owner of WG Biotech ApS and as such has sole voting and dispositive power with respect to such shares.
F3	Stock options granted to the Reporting Person pursuant to the Issuer's 2018 Equity Incentive Plan.
F4	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.