NISOURCE INC. (NI) · Insider Trading (Form 4) SEC Filing

=== SEC Form 4 — Statement of Changes in Beneficial Ownership === Document Type: 4 Period of Report: 2026-05-21 10b5-1 Pre-arranged Plan: No --- Issuer --- Name: NISOURCE INC. (NI) CIK: 0001111711 --- Reporting Owner --- Name: Yates Lloyd M CIK: 0001311411 Role: Director, Officer (Director and President & CEO) --- Non-Derivative Transactions --- [Transaction #1] Security: Common Stock Date: 2026-05-21 | Code: S (Open market sale) Shares: -19,905 | Price: $47.73 Total Value: $950,065.65 Shares Owned After: 519,556.732 | Ownership: D (Direct) Footnotes: [F1] The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $47.730 to $47.745, inclusive. The reporting person undertakes to provide to NiSource Inc., any security holder of NiSource Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote. [F2] This amount includes RSUs received pursuant to the dividend equivalent provisions of his director RSU awards from 2020 and 2021, and which are subject to the same vesting conditions as the underlying RSUs. [F3] Includes shares acquired through the NiSource Inc. Employee Stock Purchase Plan. --- Footnotes (Complete Index) --- F1: The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $47.730 to $47.745, inclusive. The reporting person undertakes to provide to NiSource Inc., any security holder of NiSource Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote. F2: This amount includes RSUs received pursuant to the dividend equivalent provisions of his director RSU awards from 2020 and 2021, and which are subject to the same vesting conditions as the underlying RSUs. F3: Includes shares acquired through the NiSource Inc. Employee Stock Purchase Plan. --- Signature --- /s/ /s/ Ashley Bancroft, Attorney-in-Fact (2026-05-26)