Ameren (NYSE: AEE) EVP Lindgren reports 2,073-share sale and tax withholding

Rhea-AI Filing Summary

Ameren Corp executive Mark C. Lindgren reported multiple stock transactions involving Ameren common stock. On March 3, 2026, he completed an open-market sale of 2,073 shares at $111.84 per share, conducted under a Rule 10b5-1 trading plan. Following this sale, his direct holdings stood at 44,983 shares.

On February 27, 2026, 2,054 shares were withheld by Ameren to satisfy tax obligations tied to vesting of performance share units and restricted stock units, a tax-withholding disposition rather than an open-market trade. As of February 28, 2026, he also held an estimated 1,733 share equivalents indirectly through the Ameren Corporation Savings Investment Plan 401(k) unitized stock fund.

Insider Trade Summary

Net Seller: 2,073 shares ($231,844)

Net Sell 3 txns

Insider Lindgren Mark C

Role Insider

Sold 2,073 shs ($232K)

Type	Security	Shares	Price	Value
Sale	Common Stock, $.01 Par Value	2,073	$111.84	$232K
Tax Withholding	Common Stock, $.01 Par Value	2,054	$113.28	$233K
holding	Common Stock, $.01 Par Value	--	--	--

Holdings After Transaction: Common Stock, $.01 Par Value — 44,983 shares (Direct); Common Stock, $.01 Par Value — 1,733 shares (Indirect, By 401(K))

Footnotes (1)

1. Represents the estimated number of share equivalents held by the reporting person in the unitized stock fund included in the Ameren Corporation Savings Investment Plan as of February 28, 2026. Shares withheld by the issuer to satisfy tax withholding obligations arising in connection with the vesting of performance share units and restricted stock units. Shares sold pursuant to a Rule 10b5-1 trading plan adopted by the reporting person.

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
Estimated average burden
hours per response:			0.5

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

X

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^*

Lindgren Mark C

(Last) (First) (Middle)

P.O. BOX 66149

(Street)

ST. LOUIS MO 63166-6149

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
AMEREN CORP [ AEE ]

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

	Director		10% Owner
	Officer (give title below)	X	Other (specify below)
			EVP & Chief HR Officer of Sub

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, $.01 Par Value								1,733(1)	I	By 401(K)
Common Stock, $.01 Par Value	02/27/2026		F		2,054	D	$113.28	47,046(2)	D
Common Stock, $.01 Par Value	03/03/2026		S		2,073	D	$111.84	44,983(3)	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. Represents the estimated number of share equivalents held by the reporting person in the unitized stock fund included in the Ameren Corporation Savings Investment Plan as of February 28, 2026.

2. Shares withheld by the issuer to satisfy tax withholding obligations arising in connection with the vesting of performance share units and restricted stock units.

3. Shares sold pursuant to a Rule 10b5-1 trading plan adopted by the reporting person.

Remarks:

	Jonathan T. Shade, Deputy Corp. Secy. for Ameren Corporation, attorney-in-fact for Mark C. Lindgren	03/03/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What insider transactions did Ameren (AEE) executive Mark C. Lindgren report?

Mark C. Lindgren reported an open-market sale of 2,073 Ameren shares and a separate tax-withholding share disposition. The transactions relate to common stock and equity award vesting, with holdings updated for both direct ownership and 401(k) share equivalents.

How many Ameren (AEE) shares did Mark C. Lindgren sell and at what price?

He sold 2,073 Ameren common shares in an open-market transaction at $111.84 per share. This trade was executed under a pre-established Rule 10b5-1 trading plan, which automates sales according to preset instructions rather than discretionary timing.

Were any of Mark C. Lindgren’s Ameren (AEE) share dispositions related to taxes?

Yes. A disposition of 2,054 Ameren shares on February 27, 2026 was to satisfy tax withholding obligations. These shares were withheld by Ameren in connection with the vesting of performance share units and restricted stock units, not sold on the open market.

How many Ameren (AEE) shares does Mark C. Lindgren hold after these transactions?

After the reported transactions, he directly owns 44,983 Ameren common shares. In addition, he holds an estimated 1,733 share equivalents indirectly through the Ameren Corporation Savings Investment Plan 401(k) unitized stock fund as of February 28, 2026.

Was the Ameren (AEE) insider sale by Mark C. Lindgren under a Rule 10b5-1 plan?

Yes. The 2,073-share open-market sale on March 3, 2026 was executed under a Rule 10b5-1 trading plan. Such plans allow insiders to schedule trades in advance, helping separate trading activity from day-to-day discretionary decisions.

What type of Ameren (AEE) security was involved in Mark C. Lindgren’s Form 4?

All reported transactions involve Ameren common stock with a par value of $0.01 per share. This includes shares sold in the open market, shares withheld for tax obligations on equity awards, and share equivalents held through the company’s 401(k) unitized stock fund.