On August 17, 2022, Mallinckrodt plc filed a Current Report on Form 8-K (the “Initial Form 8-K”) with the U.S. Securities and Exchange Commission to report, among other things, that the board of directors of Mallinckrodt had appointed Karen L. Ling as a director of Mallinckrodt on August 12, 2022. This Amendment No. 1 to the Initial Form 8-K is being filed solely to amend Item 5.02 of the Initial 8-K to report that on October 5, 2022, Ms. Ling was appointed to serve on the Human Resources and Compensation Committee of the Board.