Kaiser Aluminum (KALU) EVP granted 440 restricted stock units under 2021 plan

Rhea-AI Filing Summary

Robb Thomas H. reported acquisition or exercise transactions in this Form 4 filing.

Kaiser Aluminum executive Thomas H. Robb, EVP – Manufacturing, received an equity grant of 440 shares of common stock in the form of restricted stock units at no cash cost on February 23, 2026, under the company’s 2021 Equity and Incentive Compensation Plan.

According to the award terms, restrictions on 220 restricted stock units are scheduled to lapse on February 23, 2029, and restrictions on the remaining 220 units are scheduled to lapse on February 23, 2031, in each case subject to earlier lapse upon certain specified circumstances. Following this grant, Robb directly holds 14,944 shares of Kaiser Aluminum common stock.

Insider Trade Summary

1 transaction reported

Mixed 1 txn

Insider Robb Thomas H.

Role EVP - Manufacturing

Type	Security	Shares	Price	Value
Grant/Award	Common Stock, par value $0.01 per share	440	$0.00	--

Holdings After Transaction: Common Stock, par value $0.01 per share — 14,944 shares (Direct)

Footnotes (1)

1. Grant to the reporting person effective as of February 23, 2026 of restricted stock units under the Kaiser Aluminum Corporation 2021 Equity and Incentive Compensation Plan, as amended and restated. All restrictions on 220 restricted stock units will lapse on February 23, 2029 or earlier upon the occurrence of certain specified circumstances, and all restrictions on the remaining 220 restricted stock units will lapse on February 23, 2031 or earlier upon the occurrence of certain specified circumstances. Shares acquired pursuant to grants of restricted stock units.

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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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^*

Robb Thomas H.

(Last) (First) (Middle)

1550 W. MCEWEN DRIVE,

SUITE 500

(Street)

FRANKLIN TN 37067

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
KAISER ALUMINUM CORP [ KALU ]

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

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	EVP - Manufacturing

3. Date of Earliest Transaction (Month/Day/Year)
02/23/2026

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, par value $0.01 per share	02/23/2026		A		440(1)	A	$0.00(1)	14,944(2)	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. Grant to the reporting person effective as of February 23, 2026 of restricted stock units under the Kaiser Aluminum Corporation 2021 Equity and Incentive Compensation Plan, as amended and restated. All restrictions on 220 restricted stock units will lapse on February 23, 2029 or earlier upon the occurrence of certain specified circumstances, and all restrictions on the remaining 220 restricted stock units will lapse on February 23, 2031 or earlier upon the occurrence of certain specified circumstances.

2. Shares acquired pursuant to grants of restricted stock units.

	/s/ Cherrie I. Tsai, with power of attorney for Thomas H. Robb	02/25/2026
	** 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 transaction did Kaiser Aluminum (KALU) report for Thomas H. Robb?

Kaiser Aluminum reported that EVP – Manufacturing Thomas H. Robb acquired 440 shares through a grant of restricted stock units. The equity was issued under the 2021 Equity and Incentive Compensation Plan at no cash cost, increasing his direct holdings to 14,944 common shares.

How many restricted stock units did KALU grant to executive Thomas H. Robb?

Thomas H. Robb received a grant of 440 restricted stock units linked to Kaiser Aluminum common stock. The award was made under the 2021 Equity and Incentive Compensation Plan, reflecting part of his long-term incentive compensation rather than an open-market stock purchase.

What is the vesting schedule for Thomas H. Robb’s 440 KALU restricted stock units?

The 440 restricted stock units vest in two equal tranches of 220 units. Restrictions on 220 units lapse on February 23, 2029, and restrictions on the remaining 220 units lapse on February 23, 2031, subject to earlier lapse upon certain specified circumstances.

Did Thomas H. Robb pay cash for the 440 KALU shares reported on Form 4?

No, the 440 shares were acquired at a reported price of $0.0000 per share. They were issued as restricted stock units under Kaiser Aluminum’s 2021 Equity and Incentive Compensation Plan, making the transaction a compensation-related grant rather than a market purchase.

How many Kaiser Aluminum (KALU) shares does Thomas H. Robb own after this grant?

After receiving the 440-share restricted stock unit grant, Thomas H. Robb directly holds 14,944 shares of Kaiser Aluminum common stock. This total reflects his ownership following the reported February 23, 2026 equity award under the company’s long-term incentive compensation plan.

Under which plan were Thomas H. Robb’s KALU restricted stock units granted?

The 440 restricted stock units granted to Thomas H. Robb were issued under the Kaiser Aluminum Corporation 2021 Equity and Incentive Compensation Plan, as amended and restated. This plan governs equity-based awards used to compensate and retain key executives at the company.