[Form 4] NISOURCE INC. Insider Trading Activity

Rhea-AI Filing Summary

NiSource Inc. director and President & CEO Lloyd M. Yates reported equity compensation activity in the form of stock awards and related tax withholding. He acquired 275,962 shares of common stock on February 27, 2026 at $47.30 per share as a grant or award.

On the same date, 117,285 shares and 15,433 shares were disposed of at $47.30 per share to cover tax withholding obligations tied to the vesting of 2023 performance stock units and restricted stock units, rather than open-market sales. Following these transactions, he directly owned 539,292.483 shares, which include RSUs credited through dividend equivalents and shares acquired through the NiSource Employee Stock Purchase Plan.

Insider Trade Summary

3 transactions reported

Mixed 3 txns

Insider Yates Lloyd M

Role Director and President & CEO

Type	Security	Shares	Price	Value
Grant/Award	Common Stock	275,962	$47.30	$13.05M
Tax Withholding	Common Stock	117,285	$47.30	$5.55M
Tax Withholding	Common Stock	15,433	$47.30	$730K

Holdings After Transaction: Common Stock — 672,010.483 shares (Direct)

Footnotes (1)

1. Vesting of non-derivative performance stock units granted in 2023, which are exempt from liability under Section 16(b) of the Securities Exchange Act pursuant to rule 16b-3(d). Number of shares reported represent shares withheld to satisfy tax withholding obligations in connection with the vesting of the performance stock units above. Number of shares reported represent shares withheld to satisfy tax withholding obligations in connection with the vesting of the 2023 Restricted Stock Unit award. 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. Includes shares acquired through the NiSource Inc. Employee Stock Purchase Plan.

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Yates Lloyd M

(Last) (First) (Middle)

801 E. 86TH AVE

(Street)

MERRILLVILLE IN 46410

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
NISOURCE INC. [ NI ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Director and President & CEO

3. Date of Earliest Transaction (Month/Day/Year)
02/27/2026

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	02/27/2026		A		275,962(1)	A	$47.3	672,010.483	D
Common Stock	02/27/2026		F		117,285(2)	D	$47.3	554,725.483	D
Common Stock	02/27/2026		F		15,433(3)	D	$47.3	539,292.483(4)(5)	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. Vesting of non-derivative performance stock units granted in 2023, which are exempt from liability under Section 16(b) of the Securities Exchange Act pursuant to rule 16b-3(d).

2. Number of shares reported represent shares withheld to satisfy tax withholding obligations in connection with the vesting of the performance stock units above.

3. Number of shares reported represent shares withheld to satisfy tax withholding obligations in connection with the vesting of the 2023 Restricted Stock Unit award.

4. 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.

5. Includes shares acquired through the NiSource Inc. Employee Stock Purchase Plan.

	/s/ Ashley Bancroft, Attorney-in-Fact	03/03/2026
	** Signature of Reporting Person	Date
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