Management Change/Compensation (Form 8-K)

Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On December 29, 2025, Matthew Sepe, Chief Accounting Officer and Senior Vice President, Finance of Lumentum Holdings Inc. (the "Company"), informed the Company of his planned retirement from the Company. Mr. Sepe will serve as the Company's Senior Vice President, Finance until his retirement in fall 2026 and will step down as the Company's Chief Accounting Officer effective as of the later of (i) February 6, 2026 and (ii) the date upon which the Company files its Quarterly Report on Form 10-Qfor the three months ended December 27, 2025 (such date, the "Effective Date"). In connection with Mr. Sepe's retirement, the Board has appointed Eric Chang, who recently joined the Company as Senior Vice President, Finance, as Chief Accounting Officer effective upon the Effective Date.

Mr. Chang, 52, the Company's Senior Vice President, Finance, most recently served as Chief Financial Officer of Digilens, Inc., a privately-held manufacturer and licensor of key components of augmented reality and extended reality displays, from July 2025 until November 2025. Prior to joining Digilens, Mr. Chang served as VP, Chief Accounting Officer of Edgio, Inc., a content delivery network service provider, from October 2022 until June 2025. Prior to Edgio, Mr. Chang served as VP, Finance and Accounting of Summit Interconnect, Inc. from January 2022 until October 2022. Prior to joining Summit Interconnect, Mr. Chang served as Senior Vice President, Chief Financial Officer and Principal Accounting Officer of Aviat Networks, Inc. from February 2016 until October 2021. Mr. Chang also served as Senior Director, Corporate Controller at Micrel, Incorporated, a publicly-traded semiconductor company, from November 2013 to February 2016, and as Senior Director, Assistant Corporate Controller and Memory Business Unit Controller at Atmel Corporation, a publicly-traded semiconductor company, from June 2007 to November 2013. Earlier in his career, Mr. Chang served as a Senior Manager at Ernst & Young LLP and as a Senior Associate at PricewaterhouseCoopers LLP, planning, administering and managing audit engagements of public companies in the high-tech industry and performing technical research of accounting, Sarbanes-Oxley Section 404, financial statements presentation and disclosure issues in accordance with US GAAP and SEC requirements. Mr. Chang holds a B.S. in Accounting and Computer Information Systems from Indiana University and is a certified public accountant.

Mr. Chang's compensation is not expected to change in connection with this appointment as the Company's Chief Accounting Officer. Mr. Chang will enter into the Company's standard form of indemnification agreement, which has been previously filed with the Securities and Exchange Commission. There are no arrangements or understandings between Mr. Chang and any other persons pursuant to which he was selected as Chief Accounting Officer. There are also no family relationships between Mr. Chang and any director or executive officer of the Company, and he has no direct or indirect material interest in any transaction required to be disclosed pursuant to Item 404(a) of Regulation S-K.