Item 5. OTHER INFORMATION

During the quarter ended June 30, 2026, no director or officer of Alliant Energy, IPL or WPL adopted or terminated a Rule 10b5-1 trading arrangement or non-Rule 10b5-1 trading arrangement, as each term is defined in Item 408(a) of Regulation S-K.

Amended and Restated Bylaws

On July 29, 2026, the Board of Directors (the “Board”) of Alliant Energy Corporation (the “Company”) approved an amendment and restatement, effective July 31, 2026 (the “Amendment and Restatement”), of the Amended and Restated Bylaws of the Company, dated November 8, 2022 (the “Bylaws”).

The Amendment and Restatement amends Section 4.4 of the Bylaws to remove provisions relating to (i) the age following which directors are not eligible to be re-elected to the Board and (ii) the process by which a director must provide notice and tender a resignation to the Board following a change in employment, with such topics instead addressed within the Company’s Corporate Governance Guidelines, which are available on the Company’s investor website.

The Amendment and Restatement also amends Section 6.1 of the Bylaws to update the officers required to be elected by the Board to a specified list of officers identified in the Bylaws, together with any executive officers of the Company as defined by the rules and regulations of the Securities and Exchange Commission. Additionally, the Amendment and Restatement contains amendments to Section 6.3 and 6.6, in order to conform to the changes in Section 6.1.

The foregoing description of the Amendment and Restatement does not purport to be complete and is qualified in its entirety by reference to the full text of the Amended and Restated Bylaws, effective July 31, 2026, which is filed as Exhibit 3.1 to this Quarterly Report on Form 10-Q and is incorporated herein by reference.

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