Kim Matthew M. 4

4 · SOUTHERN CO · Filed Feb 3, 2026

AI-generated summary of this filing

Updated Feb 3, 2026

Southern Co (SO) Comptroller Matthew M. Kim Receives Shares

What Happened

Matthew M. Kim, Comptroller of Southern Co (SO), had restricted stock units and performance restricted stock units vest on January 31, 2026 and February 1, 2026. He acquired 340 shares (1/31) and 345 shares (2/1) from the vestings (price reported $0.00 because these were awards). To satisfy tax-withholding obligations, 170 shares (1/31) and 173 shares (2/1) were withheld and disposed for cash at $89.31 per share, resulting in withholding cash amounts of $15,183 and $15,451 (total ~$30,634). The filing also records related derivative settlement/conversion entries (317 and 308 units) tied to the awards.

Key Details

Transaction dates and prices:
- 2026-01-31: 340 shares acquired (M) @ $0.00; 170 shares withheld (F) @ $89.31 = $15,183; 317 derivative units disposed (M) @ $0.00.
- 2026-02-01: 345 shares acquired (M) @ $0.00; 173 shares withheld (F) @ $89.31 = $15,451; 308 derivative units disposed (M) @ $0.00.
Shares withheld to cover taxes: 170 + 173 = 343 shares (cash withheld ≈ $30,634).
Footnotes:
- F1/F4: Second 1/3 of RSUs (granted Jan 31, 2024) vested; includes 23 accrued dividend-equivalent units; shares withheld for tax.
- F3/F5: Final 1/3 of performance RSUs (granted Feb 1, 2023) vested; includes 37 accrued dividend-equivalent units; shares withheld for tax.
- F2: Withheld shares used to satisfy required state and federal tax withholding.
Shares owned after the transactions: not specified in the filing.
Filing timeliness: Report filed 2026-02-03 for transactions on 2026-01-31 and 2026-02-01 — appears to be timely.

Context

These entries reflect vesting/settlement of restricted and performance stock units (award income), not an open-market purchase or a discretionary sale for investment purposes. The shares reported as "acquired" are award settlements (price $0.00); shares marked as disposed correspond to withholding to pay taxes or to the settlement/termination of derivative units.
Withholding to cover taxes is routine for equity compensation and does not necessarily indicate a view on the company's stock. The filing does not indicate any 10% owner transactions or a 10b5-1 plan.

Form 4

Period: 2026-01-31

Comptroller

Transactions

Exercise/Conversion
Southern Company Common Stock
[F1]
2026-01-31+340→ 9,427 total
Tax Payment
Southern Company Common Stock
[F2]
2026-01-31$89.31/sh−170$15,183→ 9,257 total
Exercise/Conversion
Southern Company Common Stock
[F3]
2026-02-01+345→ 9,602 total
Tax Payment
Southern Company Common Stock
[F2]
2026-02-01$89.31/sh−173$15,451→ 9,429 total
Exercise/Conversion
Southern Co Restricted Stock Units
[F4]
2026-01-31−317→ 318 total
Exercise: $0.00→ Southern Company Common Stock (317 underlying)
Exercise/Conversion
Southern Co Restricted Stock Units
[F5]
2026-02-01−308→ 0 total
Exercise: $0.00→ Southern Company Common Stock (308 underlying)

Holdings

Footnotes (5)

[F1]Shares acquired upon vesting of second 1/3 of restricted stock units granted on January 31, 2024. Includes 23 accrued dividend equivalent units.
[F2]Shares withheld to satisfy required state and federal tax withholding requirements.
[F3]Shares acquired upon vesting of final 1/3 of performance restricted stock units granted on February 1, 2023. Includes 37 accrued dividend equivalent units.
[F4]Represents second 1/3 of restricted stock units granted on January 31, 2024. The remaining award will vest in 2027. 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.
[F5]Represents final 1/3 of performance restricted stock units granted on February 1, 2023. 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.

Signature

/s/ Brittney Anderson, Attorney-in-Fact for Matthew M. Kim|2026-02-03

1 file