ALGM: Leadership change · Company disclosure

Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers. On June 17, 2026, at the recommendation of the Nominating and Governance Committee (“NGC”) of the Board of Directors (the “Board”) of Allegro MicroSystems, Inc. (the “Company”) and in accordance with the Second Amended and Restated Stockholders Agreement, dated as of July 23, 2024, by and among the Company and Sanken Electric Co., Ltd. (the “Stockholders Agreement”), the Board took the following actions, each of which was effective on June 17, 2026: (i) expanded the size of the Board to 11 directors; (ii) elected Brian C. White to the Board as a Class III Director pursuant to Section 1(c) of the Stockholders Agreement, to serve until the Company’s 2026 annual meeting of shareholders (the “2026 Annual Meeting”) and until his successor is duly elected and qualified; and (iii) appointed Mr. White to serve as a member of the Board’s Audit Committee and as a member of the Board’s Compensation Committee. Additionally, in light of Richard R. Lury’s and Susan D. Lynch’s previously disclosed decisions not to stand for reelection at the 2026 Annual Meeting, the Board approved a decrease in the size of the Board from 11 to nine directors, effective immediately following the 2026 Annual Meeting. The Board has determined that Mr. White qualifies as an independent director pursuant to the rules of The Nasdaq Stock Market. The Board has also determined that Mr. White meets the enhanced independence requirements for audit committee members under Rule 10A-3 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and the rules of The Nasdaq Stock Market, and that Mr. White qualifies as an “audit committee financial e