CFO — Kelly Youngblood: The filing announces the appointment of an external hire as CFO to replace a predecessor, which is a significant executive change but not a departure event itself.

and shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section or incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such a filing. We do not have, and expressly disclaim, any obligation to release publicly any updates or any changes in our expectations or any change in events, condit…

and shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section or incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such a filing. We do not have, and expressly disclaim, any obligation to release publicly any updates or any changes in our expectations or any change in events, condit…

Director — Mr. Steven E. Nielsen: The Board of Directors elected Mr. Steven E. Nielsen as a new director.

and shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section or incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such a filing. We do not have, and expressly disclaim, any obligation to release publicly any updates or any changes in our expectations or any change in events, condit…

Executive Vice President, Chief Commercial and Strategy Officer — James W. Connell, Jr.: Mr. Connell resigned to pursue another opportunity.

Unregistered Sales of Equity Securities. The information set forth in

Entry Into a Material Definitive Agreement. Underwritten Offering On November 12, 2025, Centuri Holdings, Inc. (the “Company”) entered into an underwriting agreement (the “Underwriting Agreement”) with J.P. Morgan Securities LLC (“J.P. Morgan”) and Wells Fargo Securities, LLC, as representatives of the several underwriters named therein (collectively, the “Underwriters”), pursuant to which the Company agreed to issue and sell 7,441,860 shares of its common stock, par value $0.01 per share (“C…

Director — Dustin DeMaria: Dustin DeMaria was appointed to the Board of Directors.

Entry into a Material Definitive Agreement. Director Appointment and Nomination Agreement On November 10, 2025, Centuri Holdings, Inc. (the “ Company ”) entered into a Director Appointment and Nomination Agreement (the “ Agreement ”) with Carl C. Icahn and the persons and entities listed therein (collectively, the “ Icahn Group ”), pursuant to which the Company agreed to, on or prior to November 10, 2025, (i) increase the size of the board of directors of the Company (the “ Board ”) to 8 dire…

and shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section or incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such a filing. We do not have, and expressly disclaim, any obligation to release publicly any updates or any changes in our expectations or any change in events, condit…

Other Events. On September 3, 2025, Centuri Holdings, Inc. (the “Company”) entered into an underwriting agreement (the “Underwriting Agreement”) with J.P. Morgan Securities LLC (the “Underwriter”) and Southwest Gas Holdings, Inc. (the “Selling Stockholder”) relating to the offer and sale (the “Offering”) by the Selling Stockholder of 27,362,210 shares of its holdings of the Company’s common stock, par value $0.01 per share (“Centuri Common Stock”). The price to the public in the Offering was…

Other Events. On August 7, 2025, in connection with the Offering, the Company entered into an underwriting agreement (the “Underwriting Agreement”) with J.P. Morgan Securities LLC, as representative (the “Representative”) of the several underwriters named therein (collectively, the “Underwriters”) and the Selling Stockholder. Under the terms of the Underwriting Agreement, the Company, the Company’s directors and executive officers, the Selling Stockholder, the Icahn Investors and certain of t…

Entry Into a Material Definitive Agreement. In connection with the Concurrent Private Placement, the Company agreed to grant to the Icahn Investors certain resale registration rights, as set forth in that certain Registration Rights Letter Agreement, dated as of August 6, 2025, by and among the Company and the Icahn Investors (the “Icahn Letter Agreement”). Pursuant to the terms of the Icahn Letter Agreement, subject to certain circumstances, the Company agreed to register the resale of any s…

and shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section or incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such a filing. We do not have, and expressly disclaim, any obligation to release publicly any updates or any changes in our expectations or any change in events, condit…

Entry into a Material Definitive Agreement. On July 9, 2025, Centuri Holdings, Inc., a Delaware corporation (the “Company”), and Centuri Group, Inc., a Nevada corporation (“Centuri Group”), entered into the sixth amendment (the “Amendment”) to the Second Amended and Restated Credit Agreement, among the Company, Centuri Group, Centuri Canada Division Inc., the lenders party thereto, Wells Fargo Bank, National Association, as administrative agent, and the other parties named therein (as amended…

Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant. The information set forth under

Entry Into a Material Definitive Agreement. In connection with the Concurrent Private Placement, the Company agreed to grant to the Icahn Investors certain resale registration rights, as set forth in that certain Registration Rights Letter Agreement, dated as of June 13, 2025, by and among the Company and the Icahn Investors (the “Icahn Letter Agreement”). Pursuant to the terms of the Icahn Letter Agreement, subject to certain circumstances, the Company agreed to register the resale of any sh…

Other Events. On June 16, 2025, in connection with the Offering, the Company entered into an underwriting agreement (the “Underwriting Agreement”) with J.P. Morgan Securities LLC, as representative (the “Representative”) of the several underwriters named therein (collectively, the “Underwriters”) and the Selling Stockholder. Under the terms of the Underwriting Agreement, the Company, the Company’s directors and executive officers, the Selling Stockholder, the Icahn Investors and certain of th…

Other Events. On May 20, 2025, in connection with the Offering, the Company entered into an underwriting agreement (the “Underwriting Agreement”) with J.P. Morgan Securities LLC, as representative (the “Representative”) of the several underwriters named therein (collectively, the “Underwriters”) and the Selling Stockholder. Under the terms of the Underwriting Agreement, the Company, the Company’s directors and executive officers, the Selling Stockholder, the Icahn Investors and certain of the…

Entry Into a Material Definitive Agreement. In connection with the Concurrent Private Placement, the Company agreed to grant to the Icahn Investors certain resale registration rights, as set forth in that certain Registration Rights Letter Agreement, dated as of May 19, 2025, among the Company and the Icahn Investors (the “Icahn Letter Agreement”). Pursuant to the terms of the Icahn Letter Agreement, subject to certain circumstances, the Company agreed to register the resale of the shares sol…

and shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section or incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such a filing. We do not have, and expressly disclaim, any obligation to release publicly any updates or any changes in our expectations or any change in events, condit…

and shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section or incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such a filing. We do not have, and expressly disclaim, any obligation to release publicly any updates or any changes in our expectations or any change in events, condit…

principal accounting officer — Kendra Chilton: Kendra Chilton was promoted to principal accounting officer, while Gregory A. Izenstark continues as the principal financial officer.

and shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section or incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such a filing. We do not have, and expressly disclaim, any obligation to release publicly any updates or any changes in our expectations or any change in events, condit…