Southern (NYSE: SO) comptroller nets shares after RSU vesting event

Rhea-AI Filing Summary

Southern Company comptroller Matthew M. Kim reported routine equity compensation activity involving restricted stock units and common shares. On February 5, 2026, 292 Southern Company common shares were acquired at $0 upon vesting of the first third of a prior restricted stock unit grant, including 10 dividend-equivalent units. To cover state and federal tax withholding, 146 shares were surrendered at $91.08 per share, leaving 9,575 common shares held directly and 1,192.7661 shares held indirectly in a 401(k). Kim also continues to hold 562 restricted stock units after the transaction, with remaining portions of the award scheduled to vest in 2027 and 2028.

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).

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^*

Kim Matthew M.

(Last) (First) (Middle)

30 IVAN ALLEN JR. BLVD., NW

(Street)

ATLANTA GA 30308

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
SOUTHERN CO [ SO ]

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

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Comptroller

3. Date of Earliest Transaction (Month/Day/Year)
02/05/2026

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
Southern Company Common Stock	02/05/2026		M		292(1)	A	$0	9,721	D
Southern Company Common Stock	02/05/2026		F		146(2)	D	$91.08	9,575	D
Southern Company Common Stock								1,192.7661	I	401(k)

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
Southern Co Restricted Stock Units	$0	02/05/2026		M			282(3)	(3)	(3)	Southern Company Common Stock	282	$0	562	D

Explanation of Responses:

1. Shares acquired upon vesting of first 1/3 of restricted stock units granted on February 5, 2025. Includes 10 accrued dividend equivalent units.

2. Shares withheld to satisfy required state and federal tax withholding requirements.

3. Represents first 1/3 of restricted stock units granted on February 5, 2025. The remaining award will vest 1/3 in 2027 and 1/3 in 2028. Each restricted stock unit represents the right to receive, at settlement, one share of common stock. Additional units will be acquired with deemed dividends. Shares will be withheld upon vesting to satisfy tax requirements.

	/s/ Brittney Anderson, Attorney-in-Fact for Matthew M. Kim	02/09/2026
	** 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 Southern (SO) comptroller Matthew M. Kim report?

Matthew M. Kim reported vesting-related equity activity, acquiring 292 Southern Company common shares at $0 and surrendering 146 shares at $91.08 for tax withholding. These transactions stemmed from the first third of a restricted stock unit grant originally awarded on February 5, 2025.

How many Southern (SO) shares does Matthew M. Kim own after this Form 4?

After the reported transactions, Matthew M. Kim holds 9,575 Southern Company common shares directly and 1,192.7661 shares indirectly through a 401(k) plan. He also beneficially owns 562 restricted stock units that may convert into common shares upon future vesting and settlement.

What was the purpose of the 146 Southern (SO) shares surrendered by Kim?

The 146 Southern Company shares were withheld to satisfy required federal and state tax withholding obligations triggered by restricted stock unit vesting. This is a common administrative mechanism, allowing taxes to be covered using a portion of newly vested shares instead of separate cash payments.

What restricted stock unit grant is referenced in Matthew M. Kim’s Form 4 for Southern (SO)?

The Form 4 references restricted stock units granted on February 5, 2025. The February 2026 transaction represents vesting of the first one-third of that award, with the remaining portions scheduled to vest one-third in 2027 and one-third in 2028, subject to the award terms.

How many Southern (SO) restricted stock units does Kim still hold after this filing?

Following the February 5, 2026 vesting and settlement, Matthew M. Kim continues to hold 562 Southern Company restricted stock units. Each unit represents the right to receive one share of common stock at settlement, with additional units accruing as deemed dividend equivalents over time.

Does Matthew M. Kim’s Form 4 for Southern (SO) indicate a discretionary market sale?

The filing shows 146 shares coded as an “F” transaction, indicating shares withheld for tax obligations, not an open-market sale for investment purposes. The underlying event is vesting of restricted stock units, a standard component of executive compensation programs at many public companies.