NISOURCE INC.

6. Equity

ATM Program. In October 2025, we entered into eleven separate equity distribution agreements providing for the sale up to an aggregate of $1.5 billion of our common stock.

•In October 2025, we executed a forward sale agreement, which allows us to issue a fixed number of shares at a price to be settled in the future. The forward purchaser under our forward sale agreement borrowed 2,390,057 shares from third parties, which the forward purchaser sold, through its affiliated agent, at a weighted average price of $41.84 per share. We may settle the forward sale agreement in shares, cash or net shares by October 2026. Had we settled all of the shares under the forward sale agreement at June 30, 2026, we would have received approximately $99.7 million, based on a net price of $41.72 per share.

•In February 2026, we executed a forward sale agreement, which allows us to issue a fixed number of shares at a price to be settled in the future. The forward purchaser under our forward sale agreement borrowed 2,200,000 shares from third parties, which the forward purchaser sold, through its affiliated agent, at a weighted average price of $45.63 per share. We may settle the forward sale agreement in shares, cash or net shares by December 2026. Had we settled all of the shares under the forward sale agreement at June 30, 2026, we would have received approximately $100.0 million, based on a net price of $45.46 per share.

•In June 2026, we executed a forward sale agreement, which allows us to issue a fixed number of shares at a price to be settled in the future. The forward purchaser under our forward sale agreement borrowed 2,151,874 shares from third parties, which the forward purchaser sold, through its affiliated agent, at a weighted average price of $46.47 per share. We may settle the forward sale agreement in shares, cash or net shares by December 2026. Had we settled all of the shares under the forward sale agreement at June 30, 2026, we would have received approximately $99.2 million, based on a net price of $46.10 per share.

•As of June 30, 2026, the ATM program inclusive of the outstanding forward sale agreements had approximately $1.15 billion of equity capacity available. The ATM program expires in December 2028.

Preferred Stock. During the first quarter of 2026, following the issuance of final U.S. Treasury and Internal Revenue Service regulations clarifying the scope and application of the federal excise tax on stock repurchases made after December 31, 2022, we evaluated the applicability of the excise tax to our 2023 Series A Preferred Stock redemption premium. Based on this assessment, we determined that the excise tax previously recorded does not apply to these share repurchases. Accordingly, we reversed approximately $3.6 million of excise tax expense and recognized a receivable as of June 30, 2026, for the expected refund of the amounts previously remitted.