Hugh Paul ONeill - 31 Jul 2025 Form 4 Insider Report for Mallinckrodt plc

Role: EVP, Qual & Ops, Spec Brands
Signature: /s/ Mark Tyndall, Attorney-in-Fact
Issuer symbol: N/A
Transactions as of: 31 Jul 2025
Net transactions value: $0
Form type: 4
Filing time: 04 Aug 2025, 20:57:45 UTC
Previous filing: 02 Jan 2025
Next filing: 05 Jan 2026
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
ONeill Hugh Paul	EVP, Qual & Ops, Spec Brands	675 MCDONNELL BLVD., HAZELWOOD	/s/ Mark Tyndall, Attorney-in-Fact	04 Aug 2025	0002015073

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		Restricted Stock Units	Award	$0	+10,259	+300%	$0.000000	13,679	31 Jul 2025	Ordinary Shares	10,259		Direct	F1, F2

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

Explanation of Responses:

Id	Content
F1	On July 31, 2025, pursuant to the Transaction Agreement, dated as of March 13, 2025 (as amended, the "Transaction Agreement"), by and among Mallinckrodt plc (the "Issuer"), Endo, Inc. ("Endo") and Salvare Merger Sub LLC, the Issuer's wholly owned subsidiary ("Merger Sub"), the Merger Sub merged with and into Endo (the "Business Combination"), with Endo surviving the Business Combination as a wholly owned subsidiary of the Issuer.
F2	Upon consummation of the Business Combination, each performance unit ("PSU") held by the reporting person automatically converted into a restricted unit ("RSU"). Each RSU will fully vest on December 25, 2026.

Content

On July 31, 2025, pursuant to the Transaction Agreement, dated as of March 13, 2025 (as amended, the "Transaction Agreement"), by and among Mallinckrodt plc (the "Issuer"), Endo, Inc. ("Endo") and Salvare Merger Sub LLC, the Issuer's wholly owned subsidiary ("Merger Sub"), the Merger Sub merged with and into Endo (the "Business Combination"), with Endo surviving the Business Combination as a wholly owned subsidiary of the Issuer.

Upon consummation of the Business Combination, each performance unit ("PSU") held by the reporting person automatically converted into a restricted unit ("RSU"). Each RSU will fully vest on December 25, 2026.

Remarks:

This Form 4 constitutes a notice to the Issuer for purposes of Part V of the Companies Act 2014.