[Form 4] WESTLAKE CORP Insider Trading Activity

Rhea-AI Filing Summary

Westlake Corp executive Robert F. Buesinger reported multiple equity compensation transactions. On February 20, 2026, he received an employee stock option grant for 19,351 options at an exercise price of $0.00 per share, which become exercisable in three installments of 33%, 33% and 34% on February 20, 2027, 2028 and 2029. He also received 5,281 restricted stock units, each representing one share of common stock, which will fully vest on February 20, 2029.

Separately, on February 19, 2026, 1,301 shares of common stock vested upon satisfaction of performance criteria under performance stock units granted in 2023. To satisfy tax obligations from this vesting, 326 shares of common stock were disposed of at a weighted average price of $94.101 per share in multiple transactions between $94.10 and $94.29, leaving him with 38,482 common shares held directly.

Insider Trade Summary

4 transactions reported

Mixed 4 txns

Insider Buesinger Robert F.

Role EVP, PEM Segment Head

Type	Security	Shares	Price	Value
Grant/Award	Employee Option (right to buy)	19,351	$0.00	--
Grant/Award	Restricted Stock Units	5,281	$0.00	--
Tax Withholding	Common Stock	326	$94.101	$31K
Grant/Award	Common Stock	1,301	$0.00	--

Holdings After Transaction: Employee Option (right to buy) — 19,351 shares (Direct); Restricted Stock Units — 5,281 shares (Direct); Common Stock — 38,482 shares (Direct)

Footnotes (1)

1. Represents shares of common stock that vested on February 19, 2026, upon the determination by the Compensation Committee of the Issuer's Board of Directors of the satisfaction of performance criteria underlying an award of performance stock units ("PSUs") granted to the Reporting Person on February 17, 2023, under the terms of the Issuer's 2013 Omnibus Incentive Plan. Shares otherwise issuable were witheld to satisfy tax obligations arising out of vesting of the Reporting Person's PSUs. Weighted average price. These shares were sold in multiple transactions at prices ranging from $94.10 to $94.29, inclusive. The Reporting Person undertakes to provide the Issuer, any security holder of the Issuer, or the staff of the SEC, upon request, full information regarding the number of shares sold at each separate price within the range set forth above. The stock options are excercisable in three installments of 33%, 33% and 34% on February 20, 2027, 2028 and 2029, respectively. Each restricted stock unit ("RSU") represents a contingent right to recieve one share of the Issuer's common stock. All of the RSUs will vest on February 20, 2029.

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).

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^*

Buesinger Robert F.

(Last) (First) (Middle)

2801 POST OAK BLVD., STE. 600

(Street)

HOUSTON TX 77056

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
WESTLAKE CORP [ WLK ]

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

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	EVP, PEM Segment Head

3. Date of Earliest Transaction (Month/Day/Year)
02/19/2026

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	02/19/2026		A		1,301(1)	A	$0	38,808	D
Common Stock	02/20/2026		F		326(2)	D	$94.101(3)	38,482	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
Employee Option (right to buy)	$94.48	02/20/2026		A		19,351		(4)	02/20/2036	Common Stock	19,351	$0	19,351	D
Restricted Stock Units	(5)	02/20/2026		A		5,281		(6)	(6)	Common Stock	5,281	$0	5,281	D

Explanation of Responses:

1. Represents shares of common stock that vested on February 19, 2026, upon the determination by the Compensation Committee of the Issuer's Board of Directors of the satisfaction of performance criteria underlying an award of performance stock units ("PSUs") granted to the Reporting Person on February 17, 2023, under the terms of the Issuer's 2013 Omnibus Incentive Plan.

2. Shares otherwise issuable were witheld to satisfy tax obligations arising out of vesting of the Reporting Person's PSUs.

3. Weighted average price. These shares were sold in multiple transactions at prices ranging from $94.10 to $94.29, inclusive. The Reporting Person undertakes to provide the Issuer, any security holder of the Issuer, or the staff of the SEC, upon request, full information regarding the number of shares sold at each separate price within the range set forth above.

4. The stock options are excercisable in three installments of 33%, 33% and 34% on February 20, 2027, 2028 and 2029, respectively.

5. Each restricted stock unit ("RSU") represents a contingent right to recieve one share of the Issuer's common stock.

6. All of the RSUs will vest on February 20, 2029.

	Robert F. Buesinger by J. Feng, POA	02/23/2026
	** 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.