Daniel Niedzwiecki - 02 Mar 2026 Form 4 Insider Report for Lantheus Holdings, Inc. (LNTH)

Role: Chief Administrative Officer, General Counsel and Corporate Secretary
Signature: /s/ Eric M. Green, attorney-in-fact
Issuer symbol: LNTH
Transactions as of: 02 Mar 2026
Net transactions value: $0
Form type: 4
Filing time: 04 Mar 2026, 16:19:46 UTC
Previous filing: 17 Jun 2025
Next filing: 09 Mar 2026
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
Niedzwiecki Daniel	Chief Administrative Officer, General Counsel and Corporate Secretary	C/O LANTHEUS HOLDINGS, INC., 201 BURLINGTON ROAD, SOUTH BUILDING, BEDFORD	/s/ Eric M. Green, attorney-in-fact	04 Mar 2026	0001861113

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	LNTH	Common Stock	Award		+5,169	+5.9%	$0.000000^*	92,226	02 Mar 2026	Direct	F1
transaction	LNTH	Common Stock	Tax liability		-8,259	-9%	$76.30^*	83,967	02 Mar 2026	Direct

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

Explanation of Responses:

Id	Content
F1	The transaction reported in this Form 4 reflects additional shares of common stock issued by Lantheus Holdings, Inc. to the reporting person upon the vesting of relative Total Shareholder Return performance-based restricted stock units ("PSUs") that were previously granted and included in the Form 4 filed on March 6, 2023. The number of shares reported in the Form 4 reflected 100% of the target number of shares underlying the PSUs. The number of shares that actually vested under the PSUs equaled 162.8% of the target number of shares. Accordingly, the number of shares reported in this Form 4 reflects the difference between the number of shares that actually vested under the PSUs and the target number of shares originally included in the Form 4.

Content

The transaction reported in this Form 4 reflects additional shares of common stock issued by Lantheus Holdings, Inc. to the reporting person upon the vesting of relative Total Shareholder Return performance-based restricted stock units ("PSUs") that were previously granted and included in the Form 4 filed on March 6, 2023. The number of shares reported in the Form 4 reflected 100% of the target number of shares underlying the PSUs. The number of shares that actually vested under the PSUs equaled 162.8% of the target number of shares. Accordingly, the number of shares reported in this Form 4 reflects the difference between the number of shares that actually vested under the PSUs and the target number of shares originally included in the Form 4.

Remarks:

Chief Administrative Officer, General Counsel and Corporate Secretary