Exhibit 1.1

Execution Version

WESTLAKE CORPORATION

$600,000,000 5.550% Senior Notes due 2035

$600,000,000 6.375% Senior Notes due 2055

UNDERWRITING AGREEMENT

November 4, 2025

Underwriting Agreement

November 4, 2025

BOFA SECURITIES, INC.

DEUTSCHE BANK SECURITIES INC.

J.P. MORGAN SECURITIES LLC

WELLS FARGO SECURITIES, LLC

As Representatives of the several Underwriters

c/o BofA Securities, Inc.

One Bryant Park

New York, New York 10036

c/o Deutsche Bank Securities Inc.

1 Columbus Circle

New York, New York 10019

c/o J.P. Morgan Securities LLC

270 Park Ave

New York, New York 10017

c/o Wells Fargo Securities, LLC

550 South Tryon Street, 5th Floor

Charlotte, North Carolina 28202

Ladies and Gentlemen:

Introductory. Westlake Corporation, a Delaware corporation (the “Company”), proposes to issue and sell to the several underwriters named in Schedule A (the “Underwriters”), acting severally and not jointly, the respective amounts set forth in such Schedule A of $600,000,000 aggregate principal amount of the Company’s 5.550% Senior Notes due 2035 (the “2035 Notes”) and $600,000,000 aggregate principal amount of the Company’s 6.375% Senior Notes due 2055 (the “2055 Notes” and, together with the 2035 Notes, the “Notes”). BofA Securities, Inc., Deutsche Bank Securities Inc., J.P. Morgan Securities LLC and Wells Fargo Securities, LLC have agreed to act as representatives of the several Underwriters (in such capacity, collectively, the “Representatives”) in connection with the offering and sale of the Notes.

The Notes will be issued pursuant to an indenture, dated as of January 1, 2006 (the “Base Indenture”), among the Company, the potential subsidiary guarantors party thereto and JPMorgan Chase Bank, National Association, as trustee, as amended and supplemented by that certain Fifteenth Supplemental Indenture (the “Supplemental Indenture”), dated as of November 6, 2025 between the Company and The Bank of New York Mellon Trust Company, N.A., as successor in interest to JPMorgan Chase Bank, National Association, as trustee (the “Trustee”). The Base Indenture as amended and supplemented by the Supplemental Indenture is referred to herein as the “Indenture.”

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The Notes will be issued in book-entry form and registered in the name of Cede & Co., as nominee of The Depository Trust Company (the “Depositary”), pursuant to a Letter of Representations, dated January 5, 2006 (the “DTC Agreement”), among the Company and the Depositary. The Notes, the Indenture, the DTC Agreement and this Agreement are referred to herein collectively as the “Operative Documents.”

The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-3 (File No. 333-291208), which registration statement contains a base prospectus dated October 31, 2025 (the “Base Prospectus”), to be used in connection with the public offering and sale of debt securities, including the Notes, and other securities of the Company under the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder (collectively, the “Securities Act”), and the offering thereof from time to time in accordance with Rule 415 under the Securities Act. Such registration statement, including the financial statements, exhibits and schedules thereto, as amended to the date of this Agreement, including any required information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430B under the Securities Act, is called the “Registration Statement.” The term “Prospectus” shall mean the final prospectus supplement relating to the Notes, together with the Base Prospectus, that is first filed pursuant to Rule 424(b) after the date and time that this Agreement is executed (the “Execution Time”) by the parties hereto. The term “Preliminary Prospectus” shall mean any preliminary prospectus supplement relating to the Notes, together with the Base Prospectus, that is first filed with the Commission pursuant to Rule 424(b). Any reference herein to the Registration Statement, the Preliminary Prospectus or the Prospectus shall be deemed to refer to and include the documents that are or are deemed to be incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act prior to 2:50 p.m. (New York City time) on November 4, 2025 (the “Initial Sale Time”). All references in this Agreement to the Registration Statement, the Preliminary Prospectus, the Prospectus, or any amendments or supplements to any of the foregoing, shall include any copy thereof filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval System (“EDGAR”).

All references in this Agreement to financial statements and schedules and other information which is “contained,” “included” or “stated” (or other references of like import) in the Registration Statement, the Prospectus or the Preliminary Prospectus shall be deemed to mean and include all such financial statements and schedules and other information which is or is deemed to be incorporated by reference in the Registration Statement, the Prospectus or the Preliminary Prospectus, as the case may be, prior to the Initial Sale Time; and all references in this Agreement to amendments or supplements to the Registration Statement, the Prospectus or the Preliminary Prospectus shall be deemed to include the filing of any document under the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder (collectively, the “Exchange Act”), which is or is deemed to be incorporated by reference in the Registration Statement, the Prospectus or the Preliminary Prospectus, as the case may be, after the Initial Sale Time.

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The proceeds of this offering (the “Proceeds”) will be used to fund the repurchase of the Company’s outstanding 3.600% Senior Notes due 2026 pursuant to a cash tender offer, upon the terms and subject to the conditions set forth in the related offer to purchase dated the date hereof and notice of guaranteed delivery. The Company anticipates using any remaining net proceeds to fund the purchase price of its pending acquisition of the ACI/Perplastic Group and for general corporate purposes, including working capital management.

The Company hereby confirms its agreement with the Underwriters as follows:

Section 1. Representations and Warranties of the Company.

The Company hereby represents, warrants and covenants to each Underwriter as of the date hereof, as of the Initial Sale Time and as of the Closing Date (in each case, a “Representation Date”), as follows:

a) Compliance with Registration Requirements. The Company meets the requirements for use of Form S-3 under the Securities Act. The Registration Statement has become effective under the Securities Act and no stop order suspending the effectiveness of the Registration Statement has been issued under the Securities Act and no proceedings for that purpose have been instituted or are pending or, to the best of the Company’s knowledge, are contemplated or threatened by the Commission, and any request on the part of the Commission for additional information has been complied with. In addition, the Indenture has been duly qualified under the Trust Indenture Act of 1939, as amended, and the rules and regulations promulgated thereunder (collectively, the “Trust Indenture Act”).

At the respective times the Registration Statement and any post-effective amendments thereto became effective and at each Representation Date, the Registration Statement and any amendments thereto (i) complied and will comply in all material respects with the requirements of the Securities Act and the Trust Indenture Act, and (ii) did not and will not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading. At the date of the Prospectus and at the Closing Date, neither the Prospectus nor any amendments or supplements thereto included or will include an untrue statement of a material fact or omitted or will omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading. Notwithstanding the foregoing, the representations and warranties in this subsection shall not apply to (i) that part of the Registration Statement which constitutes the Statement of Eligibility on Form T-1 of the Trustee under the Trust Indenture Act and (ii) statements in or omissions from the Registration Statement or any post-effective amendment or the Prospectus or any amendments or supplements thereto made in reliance upon and in conformity with information furnished to the Company in writing by any of the Underwriters through the Representatives expressly for use therein, it being understood and agreed that the only such information furnished by any Underwriter through the Representatives consists of the information described as such in Section 8 hereof.

Each Preliminary Prospectus and the Prospectus, at the time each was filed with the Commission, complied in all material respects with the Securities Act, and the Preliminary Prospectus and the Prospectus delivered to the Underwriters for use in connection with the offering of the Notes will, at the time of such delivery, be identical to any electronically transmitted copies thereof filed with the Commission pursuant to EDGAR, except to the extent permitted by Regulation S-T.

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b) Disclosure Package. The term “Disclosure Package” shall mean (i) the Preliminary Prospectus dated November 4, 2025, (ii) the issuer free writing prospectuses as defined in Rule 433 of the Securities Act (each, an “Issuer Free Writing Prospectus”), if any, identified in Annex I hereto and (iii) any other free writing prospectus that the parties hereto shall hereafter expressly agree in writing to treat as part of the Disclosure Package. As of the Initial Sale Time, the Disclosure Package did not contain any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading. The preceding sentence does not apply to statements in or omissions from the Disclosure Package based upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives specifically for use therein.

c) Incorporated Documents. The documents incorporated or deemed to be incorporated by reference in the Registration Statement, the Preliminary Prospectus and the Prospectus (i) at the time they were or hereafter are filed with the Commission, complied or will comply in all material respects with the requirements of the Exchange Act and (ii) when read together with the other information in the Disclosure Package, at the Initial Sale Time, and when read together with the other information in the Prospectus, at the date of the Prospectus and at the Closing Date, did not or will not include an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading.

d) Company is a Well-Known Seasoned Issuer. (i) At the time of filing the Registration Statement, (ii) at the time of the most recent amendment thereto for the purposes of complying with Section 10(a)(3) of the Securities Act (whether such amendment was by post-effective amendment, incorporated report filed pursuant to Section 13 or 15(d) of the Exchange Act or form of prospectus), (iii) at the time the Company or any person acting on its behalf (within the meaning, for this clause only, of Rule 163(c) of the Securities Act) made any offer relating to the Notes in reliance on the exemption of Rule 163 of the Securities Act, and (iv) as of the Execution Time, the Company was and is a “well known seasoned issuer” as defined in Rule 405 of the Securities Act. The Registration Statement is an “automatic shelf registration statement,” as defined in Rule 405 of the Securities Act, that automatically became effective not more than three years prior to the Execution Time; the Company has not received from the Commission any notice pursuant to Rule 401(g)(2) of the Securities Act objecting to use of the automatic shelf registration statement form and the Company has not otherwise ceased to be eligible to use the automatic shelf registration statement form.

e) Company is not an Ineligible Issuer. (i) At the time of filing the Registration Statement and (ii) as of the Execution Time (with such date being used as the determination date for purposes of this clause (ii)), the Company was not and is not an Ineligible Issuer (as defined in Rule 405 of the Securities Act), without taking account of any determination by the Commission pursuant to Rule 405 of the Securities Act that it is not necessary that the Company be considered an Ineligible Issuer.

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f) Issuer Free Writing Prospectuses. Each Issuer Free Writing Prospectus, as of its issue date and at all subsequent times through the completion of the offering of Notes under this Agreement or until any earlier date that the Company notified or notifies the Representatives as described in the next sentence, did not, does not and will not include any information that conflicted, conflicts or will conflict with the information contained in the Registration Statement, the Preliminary Prospectus or the Prospectus. If at any time following issuance of an Issuer Free Writing Prospectus there occurred or occurs an event or development as a result of which such Issuer Free Writing Prospectus conflicted or would conflict with the information contained in the Registration Statement, the Preliminary Prospectus or the Prospectus the Company has promptly notified or will promptly notify the Representatives and has promptly amended or supplemented or will promptly amend or supplement, at its own expense, such Issuer Free Writing Prospectus to eliminate or correct such conflict. The foregoing two sentences do not apply to statements in or omissions from any Issuer Free Writing Prospectus based upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives specifically for use therein.

g) Distribution of Offering Material By the Company. The Company has not distributed and will not distribute, prior to the later of the Closing Date and the completion of the Underwriters’ distribution of the Notes, any offering material in connection with the offering and sale of the Notes other than the Registration Statement, the Preliminary Prospectus, the Prospectus, any Issuer Free Writing Prospectus reviewed and consented to by the Representatives and included in Annex I hereto or any electronic road show or other written communications reviewed and consented to by the Representatives and listed on Annex II hereto (each a, “Company Additional Written Communication”). Each such Company Additional Written Communication, when taken together with the Disclosure Package, did not, and at the Closing Date will not, contain any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading. The preceding sentence does not apply to statements in or omissions from the Company Additional Written Communication based upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives specifically for use therein.

h) No Applicable Registration or Other Similar Rights. There are no persons with registration or other similar rights to have any equity or debt securities registered for sale under the Registration Statement which have not been so registered or included in the offering contemplated by this Agreement, except for such rights as will have been duly waived prior to the Closing Date.

i) The Underwriting Agreement. This Agreement has been duly authorized, executed and delivered by the Company.

j) Authorization of the Indenture. The Base Indenture has been duly qualified under the Trust Indenture Act and has been duly authorized, executed and delivered by the Company and constitutes a valid and binding agreement of the Company, enforceable against the Company in accordance with its terms, except as the enforcement thereof may be limited by bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium, or other similar laws relating to or affecting the rights and remedies of creditors or by general equitable principles and public policy.

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The Supplemental Indenture has been duly authorized by the Company, and at the Closing Date, will have been duly executed and delivered by the Company and, assuming due authorization, execution and delivery by the Trustee, will constitute a valid and binding agreement of the Company, enforceable against the Company in accordance with its terms, except as the enforcement thereof may be limited by bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium, or other similar laws relating to or affecting the rights and remedies of creditors or by general equitable principles and public policy.

k) Authorization of the Notes. The Notes to be purchased by the Underwriters from the Company are in the form contemplated by the Indenture, have been duly authorized for issuance and sale pursuant to this Agreement and the Indenture and, at the Closing Date, will have been duly executed by the Company and, assuming due authentication of the Notes by the Trustee, upon delivery to the Underwriters against payment therefor in accordance with the terms hereof, will constitute valid and binding obligations of the Company, enforceable in accordance with their terms, except as the enforcement thereof may be limited by bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium or other similar laws relating to or affecting the rights and remedies of creditors or by general equitable principles, and will be entitled to the benefits of the Indenture.

l) [Reserved].

m) Description of the Notes and the Indenture. The Notes and the Indenture conform in all material respects to the descriptions thereof contained in the Disclosure Package and the Prospectus.

n) Accuracy of Statements. The statements in each of the Disclosure Package and the Prospectus under the captions “Description of the Senior Notes”, “Description of Debt Securities”, “Description of Capital Stock” and “Material United States Federal Income Tax Considerations”, in each case, insofar as such statements constitute a summary of the legal matters, documents or proceedings referred to therein, fairly present and summarize, in all material respects, the matters referred to therein.

o) No Material Adverse Change. Except as otherwise disclosed in the Disclosure Package, subsequent to the respective dates as of which information is given in the Disclosure Package, there has been no material adverse change, or any development that could reasonably be expected to result in a material adverse change, in the condition, financial or otherwise, or in the earnings, management, business, properties or results of operations, whether or not arising from transactions in the ordinary course of business, of the Company and its subsidiaries, considered as one entity (any such change is called a “Material Adverse Change”).

p) Independent Accountants. PricewaterhouseCoopers LLP, who have audited certain of the Company’s financial statements incorporated by reference in the Registration Statement, the Preliminary Prospectus and the Prospectus, are independent public accountants with respect to the Company as required by the Securities Act and the Exchange Act and are an independent registered public accounting firm with the Public Company Accounting Oversight Board.

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q) [Reserved].

r) Incorporation and Good Standing of the Company. The Company has been duly incorporated and is an existing corporation in good standing under the laws of its state of incorporation, with power and authority to own its properties and conduct its business as described in the Disclosure Package and the Prospectus; and the Company is duly qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification, except where the failure to be so qualified or in good standing would not, individually or in the aggregate, have a material adverse effect (i) on the current or future condition (financial or other), business, properties or results of operations of the Company and any subsidiary of the Company, taken as a whole or (ii) on the ability of the Company to perform its obligations under, and consummate the transactions contemplated by, the Operative Documents (a “Material Adverse Effect”). The Company has all requisite power and authority to enter into the Operative Documents to which each is a party and to authorize, issue and sell the Notes, as contemplated by this Agreement.

s) Incorporation and Good Standing of Other Subsidiaries. Each subsidiary of the Company has been duly incorporated or formed and is an existing corporation or other entity in good standing under the laws of the jurisdiction of its incorporation or organization, with power and authority to own its properties and conduct its business as described in the Disclosure Package and the Prospectus; and each such subsidiary is duly qualified to do business as a foreign corporation or other entity in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification, except where the failure to be so qualified or in good standing would not, individually or in the aggregate, have a Material Adverse Effect.

t) Capitalization and Other Matters. The Company has an authorized capitalization as set forth in the Disclosure Package and the Prospectus. All of the issued and outstanding shares of capital stock of the Company have been duly authorized and validly issued and are fully paid and non-assessable. All of the issued and outstanding shares of capital stock of each subsidiary of the Company has been duly authorized and validly issued and is fully paid and nonassessable and the shares of capital stock of each subsidiary owned by the Company, directly or through subsidiaries, is owned free from liens, encumbrances and defects, except as (i) would not, individually or in the aggregate, have a Material Adverse Effect or (ii) disclosed in the Disclosure Package and the Prospectus.

u) No Broker or Finder’s Fee. Except as disclosed in the Disclosure Package and the Prospectus, there are no contracts, agreements or understandings between the Company and any person that would give rise to a valid claim against the Company or any Underwriter for a brokerage commission, finder’s fee or other like payment in connection with the sale of the Notes.

v) No Further Authorizations or Approvals Required.

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No consent, approval, authorization, or order of, or filing with, any governmental agency of the United States or body or any court with jurisdiction in the United States over the Company or any of its properties is required to be obtained or made by the Company for the consummation of the transactions contemplated by this Agreement in connection with the sale of the Notes, except such as have been obtained and made or will be obtained and made prior to the date hereof under the Securities Act (provided, however, a filing with the Commission pursuant to Rule 424(b), Rule 430, Rule 430B or Rule 433 may be made after the date hereof so long as such filing is made within the time period specified in the applicable provision of such rule) and such as may be required under state securities or blue sky laws.

w) No Conflicts. The execution, delivery and performance of the Operative Documents by the Company, and the consummation of the transactions herein contemplated, will not conflict with or result in a breach or violation of any of the terms and provisions of, or constitute a default under, (A) any statute, any rule, regulation or order of any governmental agency or body or any court, domestic or foreign, having jurisdiction over the Company or any subsidiary of the Company or any of their respective properties, or (B) any agreement or instrument to which the Company or any subsidiary of the Company is a party or by which any of them is bound or to which any of their respective properties is subject, or (C) any of their respective charters or by-laws or other organizational documents, other than, in the case of clauses (A) or (B) above, such conflicts, breaches, violations or defaults that would not, individually or in the aggregate, have a Material Adverse Effect.

x) Title to Properties. Except as disclosed in the Disclosure Package and the Prospectus, the Company and each of the subsidiaries of the Company has (A) good and indefeasible title to (in the case of fee interests in real property), (B) valid leasehold interests in (in the case of leasehold interests in real or personal property) and (C) valid title to (in the case of all other personal property), all of its respective properties and assets reflected in the Company’s consolidated financial statements included in the Registration Statement, the Disclosure Package and the Prospectus free and clear of all liens, encumbrances and defects, except for such failures to have such title to or interests in, and for such liens, encumbrances and defects, as would not, individually or in the aggregate, have a Material Adverse Effect.

y) All Necessary Permits. The Company and each subsidiary of the Company possess adequate certificates, authorities or permits issued by appropriate governmental agencies or bodies necessary to conduct the business now operated by them, except as would not, individually or in the aggregate, have a Material Adverse Effect, and have not received any notice of proceedings relating to the revocation or modification of any such certificate, authority or permit that, if determined adversely to the Company or any such subsidiary, would individually or in the aggregate, have a Material Adverse Effect.

z) Labor Matters. No labor dispute with the employees of the Company or any subsidiary of the Company exists or, to the knowledge of the Company is imminent that would reasonably be expected to have a Material Adverse Effect.

aa) Intellectual Property Rights. The Company and the subsidiaries of the Company own, possess or can acquire on reasonable terms, adequate trademarks, trade names and other rights to inventions, know-how, patents, copyrights and other intellectual property (collectively, “intellectual property rights”) necessary to conduct the business now operated by them, or presently employed by them, except as would not, individually or in the aggregate, have a Material Adverse Effect, and have not received any notice of infringement of or conflict with asserted rights of others with respect to any intellectual property rights that, if determined adversely to the Company or any such subsidiary, would individually or in the aggregate have a Material Adverse Effect.

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bb) Compliance with Environmental Laws. Except as disclosed in the Disclosure Package and the Prospectus, and except for such matters as would not, individually or in the aggregate, have a Material Adverse Effect or be required to be disclosed in the Prospectus pursuant to the Securities Act, the Company and the subsidiaries of the Company (or, to the knowledge of the Company, any other entity for whose acts or omissions the Company is or may be liable) (1) are conducting and have conducted their businesses, operations and facilities in compliance with Environmental Laws (as defined below); (2) possess and maintain in full force and effect any and all permits, licenses or registrations required under Environmental Law for the conduct of their businesses (“Environmental Permits”); (3) have not, pursuant to any contract, assumed responsibility to cure any currently identified material liability under Environmental Law or to remediate any currently identified Hazardous Substances (as defined below) spill or release; (4) have not received any notice from a governmental authority or any other third party alleging any violation of Environmental Law or liability thereunder (including, without limitation, liability as a “potentially responsible party” and/or for costs of investigating or remediating sites containing Hazardous Substances and/or damages to natural resources); (5) are not subject to any pending or, to the knowledge of the Company, threatened claim or other legal proceeding under any Environmental Laws against the Company or its subsidiaries; (6) do not have knowledge of any pending Environmental Law, or any unsatisfied condition in an Environmental Permit, or any release of Hazardous Substances that, individually or in the aggregate, can reasonably be expected to require any material capital expenditures to maintain the Company’s or the subsidiaries’ compliance with Environmental Law or with their Environmental Permits; and (7) does not (A) rely on any third party for an indemnity for, or the contractual assumption of, any material remediation obligation or liability under Environmental Law and (B) have reasonable cause to believe that such third party will default in its obligation to comply with such indemnity or contractual assumption. As used in this paragraph, “Environmental Laws” means any and all applicable federal, state, local, and foreign laws, statutes, ordinances, rules, regulations, requirements and common law, or any enforceable administrative or judicial interpretation, order, consent, decree or judgment thereof, relating to pollution or the protection of human health or the environment, including, without limitation, those relating to, regulating, or imposing liability or standards of conduct concerning (i) noise or odor, (ii) emissions, discharges, releases or threatened releases of Hazardous Substances into ambient air, surface water, groundwater or land, (iii) the generation, manufacture, processing, distribution, use, treatment, storage, disposal, release, transport or handling of, or exposure to, Hazardous Substances, (iv) the protection of wildlife or endangered or threatened species, or (v) the investigation, remediation or cleanup of, or exposure to, any Hazardous Substances. As used in this paragraph, “Hazardous Substances” means pollutants, contaminants or hazardous, dangerous or toxic substances, materials, constituents or wastes or petroleum, petroleum products and their breakdown constituents, or any other chemical substance regulated under Environmental Laws.

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cc) No Undisclosed Material Action or Proceeding. Except as disclosed in the Disclosure Package and the Prospectus, there are no pending actions, suits or proceedings against or affecting the Company, any subsidiary of the Company or any of their respective properties that, if determined adversely to the Company or any subsidiary of the Company, would individually or in the aggregate have a Material Adverse Effect, or which are otherwise material in the context of the sale of the Notes; and no such actions, suits or proceedings are threatened or, to the Company’s knowledge, contemplated.

dd) Financial Statements and Financial Information. The financial statements included in the Registration Statement, the Disclosure Package and the Prospectus present fairly, in all material respects, the financial position of the Company and its consolidated subsidiaries as of the dates shown and their results of operations and cash flows for the periods shown, and such financial statements comply as to form in all material respects with the accounting requirements of the Securities Act and have been prepared in conformity with the generally accepted accounting principles in the United States (“GAAP”) applied on a consistent basis. No other financial statements are required to be included in the Registration Statement. The summary financial information included in the Disclosure Package and the Prospectus have been derived from the financial statements included in the Disclosure Package and the Prospectus. The interactive data in eXtensible Business Reporting Language incorporated by reference in the Registration Statement, the Disclosure Package and the Prospectus fairly presents the information called for in all material respects and has been prepared in accordance with the Commission’s rules and guidelines applicable thereto. All non-GAAP financial information included in the Registration Statement complies with the requirements of Item 10 of Regulation S-K under the Securities Act.

ee) [Reserved].

ff) [Reserved].

gg) Not an Investment Company. The Company is not and, after giving effect to the offering and sale of the Notes and the application of the proceeds thereof as described in the Disclosure Package and the Prospectus, will not be, an “investment company” as defined in the Investment Company Act of 1940.

hh) Tax Law Compliance. The Company and the subsidiaries of the Company have filed all federal, state, local and non-U.S. income and franchise tax returns required to be filed through the date hereof, except where the failure to so file such returns would not, individually or in the aggregate, have a Material Adverse Effect, and have paid all taxes due thereon, and other than tax deficiencies which the Company or any subsidiary of the Company is contesting in good faith and for which adequate reserves have been provided in accordance with GAAP, there is no tax deficiency that has been asserted against the Company or any subsidiary of the Company that would, individually or in the aggregate, have a Material Adverse Effect.

ii) No Price Stabilization or Manipulation. Prior to the date hereof, neither the Company nor any of its affiliates has taken any action which is designed to or which has constituted or which might have been expected to cause or result in unlawful stabilization or manipulation of the price of any security of the Company in connection with the offering of the Notes.

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jj) Internal Controls. The Company and the subsidiaries of the Company maintain a system of internal accounting controls sufficient to provide reasonable assurance that (i) transactions are executed in accordance with management’s general or specific authorization and (ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with GAAP and to maintain accountability for assets.

kk) Disclosure Controls and Procedures. The Company and the subsidiaries of the Company maintain disclosure controls and procedures (as defined in Rule 13a-14 of the Exchange Act) designed to ensure that information required to be disclosed by the Company, including its consolidated subsidiaries, in the reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported in accordance with the Exchange Act. The Company has carried out evaluations, under the supervision and with the participation of the Company’s management, of the effectiveness of the design and operation of the Company’s disclosure controls and procedures in accordance with Rule 13a-15 of the Exchange Act.

ll) Regulation T, U or X. Neither the Company nor any of its subsidiaries nor any agent thereof acting on their behalf has taken, and none of them will take, any action that might cause this Agreement or the issuance or sale of the Notes to violate Regulation T, Regulation U or Regulation X of the Board of Governors of the Federal Reserve System.

mm) No Change in Ratings. No “nationally recognized statistical rating organization” as such term is defined for purposes of Section 3(a)(62) of the Exchange Act (i) has imposed (or has informed the Company that it is considering imposing) any condition (financial or otherwise) on the Company’s retaining any rating assigned to the Company or any securities of the Company or (ii) has indicated to the Company that it is considering (a) the downgrading, suspension, or withdrawal of, or any review for a possible change that does not indicate the direction of the possible change in, any rating so assigned or (b) any change in the outlook for any rating of the Company or any securities of the Company.

nn) Related Party Transactions. There are no business relationships or related-party transactions involving the Company, any of the Company’s subsidiaries or any other person required to be described in the Preliminary Prospectus or the Prospectus that have not been described as required.

oo) No Unlawful Contributions or Other Payments. None of the Company, any of its subsidiaries or, to the knowledge of the Company, any director, officer, agent, employee or affiliate or any of its subsidiaries is aware of or has taken any action, directly or indirectly, that would result in a violation by such persons of either (i) the Foreign Corrupt Practices Act of 1977, as amended, and the rules and regulations thereunder (the “FCPA”), including, without limitation, making use of the mails or any means or instrumentality of interstate commerce corruptly in furtherance of an offer, payment, promise to pay or authorization of the payment of any money, or other property, gift, promise to give, or authorization of the giving of anything of value to any “foreign official” (as such term is defined in the FCPA) or any foreign political party or official thereof or any candidate for foreign political office, in contravention of the FCPA, (ii) the U.K. Bribery Act 2010 (the “Bribery Act”) or (iii) the OECD Convention on Combating Bribery of Foreign Public Officials in International Business Transactions, and the Company, its subsidiaries and, to the knowledge of the Company, its other affiliates have conducted their businesses in compliance with the FCPA and the Bribery Act and have instituted and maintain policies and procedures designed to ensure, and which are reasonably expected to continue to ensure, continued compliance therewith. No part of the proceeds of the offering will be used, directly or indirectly, in violation of the FCPA or the Bribery Act or similar law of any other relevant jurisdiction, or the rules or regulations thereunder.

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pp) No Conflict with Anti-Money Laundering Laws. The operations of the Company and its subsidiaries are and have been conducted at all times in compliance in all material respects with applicable financial recordkeeping and reporting requirements of the Currency and Foreign Transactions Reporting Act of 1970, as amended, the anti-money laundering statutes of all applicable jurisdictions, the rules and regulations thereunder and any related or similar rules, regulations or guidelines issued, administered or enforced by any governmental agency (collectively, the “Anti-Money Laundering Laws”) and no action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Company or any of its subsidiaries with respect to the Anti-Money Laundering Laws is pending or, to the knowledge of the Company, threatened.

qq) No Conflict with OFAC Laws. None of the Company, any of its subsidiaries or, to the knowledge of the Company, any director, officer, agent, employee, affiliate or representative of the Company or any of its subsidiaries is an individual or entity (“Person”) currently the subject or target of any sanctions administered or enforced by the United States Government, including, without limitation, the U.S. Department of the Treasury’s Office of Foreign Assets Control (“OFAC”), the United Nations Security Council (“UNSC”), the European Union, His Majesty’s Treasury (“HMT”), or other relevant sanctions authority (collectively, “Sanctions”), nor is the Company located, organized or resident in a country or territory that is the subject of Sanctions; and the Company will not directly or indirectly use the proceeds of the sale of the Notes, or lend, contribute or otherwise make available such proceeds to any subsidiaries, joint venture partners or other Person, to fund or facilitate any activities of or business with any Person, or in any country or territory, that, at the time of such funding or facilitating, is the subject of Sanctions or in any other manner that will result in a violation by any Person (including any Person participating in the transaction, whether as underwriter, advisor, investor or otherwise) of Sanctions.

rr) Cybersecurity. (A) There has been no material security breach or incident, unauthorized access or disclosure, or other compromise of or relating to the Company’s or its subsidiaries’ information technology and computer systems, networks, hardware, software, data and databases (including the data and information of their respective customers, employees, suppliers, vendors and any third party data maintained, processed or stored by the Company and its subsidiaries) (collectively, “IT Systems and Data”), nor any material investigations under internal review relating to the same; and (B) the Company and its subsidiaries have implemented commercially reasonable controls, policies, procedures, and technological safeguards to maintain and protect the integrity, continuous operation, redundancy and security of their IT Systems and Data reasonably consistent with industry standards and practices, or as required by applicable regulatory standards. The Company and its subsidiaries are presently in material compliance with all applicable laws or statutes and all judgments, orders, rules and regulations of any court or arbitrator or governmental or regulatory authority, internal policies and contractual obligations relating to the privacy and security of IT Systems and Data and to the protection of such IT Systems and Data from unauthorized use, access, misappropriation or modification.

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Any certificate signed by an officer of the Company and delivered to the Representatives or to counsel for the Underwriters in connection with the offering of the Notes shall be deemed to be a representation and warranty by the Company to each Underwriter as to the matters set forth therein.

Section 2. Purchase, Sale and Delivery of the Notes.

a) The Notes. The Company agrees to issue and sell to the several Underwriters, severally and not jointly, all of the Notes upon the terms herein set forth. On the basis of the representations, warranties and agreements herein contained, and upon the terms but subject to the conditions herein set forth, the Underwriters agree, severally and not jointly, to purchase from the Company (i) the aggregate principal amount of 2035 Notes, set forth opposite their names on Schedule A at a purchase price of 99.067% of the principal amount of the 2035 Notes and (ii) the aggregate principal amount of 2055 Notes, set forth opposite their names on Schedule A at a purchase price of 98.474% of the principal amount of the 2055 Notes, in each case, payable on the Closing Date.

b) The Closing Date. Delivery of certificates for the Notes in global form to be purchased by the Underwriters and payment therefor shall be made at the offices of Davis Polk & Wardwell LLP, 450 Lexington Avenue, New York, New York 10017 (or such other place as may be agreed to by the Company and the Representatives) at or around 10:00 a.m., New York City time, on November 6, 2025, or such other time and date as the Underwriters and the Company shall mutually agree (the time and date of such closing are called the “Closing Date”).

c) Public Offering of the Notes. The Representatives hereby advise the Company that the Underwriters intend to offer for sale to the public, as described in the Disclosure Package and the Prospectus, their respective portions of the Notes as soon after the Execution Time as the Representatives, in their sole judgment, have determined is advisable and practicable.

d) Payment for the Notes. Payment for and Delivery of the Notes. The Company will deliver against payment of the purchase price the Notes in the form of one or more permanent global securities in definitive form (the “Global Securities”) deposited with the Trustee as custodian for The Depository Trust Company (“DTC”) and registered in the name of Cede & Co., as nominee for DTC. Payment for the Notes shall be made by the Underwriters in Federal (same day) funds by wire transfer to an account at a bank reasonably acceptable to the Underwriters specified by the Company, at 10:00 a.m., New York City time, on November 6, 2025, or at such other time not later than seven full business days thereafter as the Underwriters and the Company determine, against delivery to the Trustee as custodian for DTC of the Global Securities representing all of the Notes. The form of Global Securities will be made available for checking at the office of Baker Botts L.L.P., 910 Louisiana Street, Houston, Texas 77002 at least 24 hours prior to the Closing Date.

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It is understood that the Representatives have been authorized, for their own accounts and for the accounts of the several Underwriters, to accept delivery of and receipt for, and make payment of the purchase price for, the Notes that the Underwriters have agreed to purchase. The Representatives may (but shall not be obligated to) make payment for any Notes to be purchased by any Underwriter whose funds shall not have been received by the Representatives by the Closing Date for the account of such Underwriter, but any such payment shall not relieve such Underwriter from any of its obligations under this Agreement.

Section 3. Covenants of the Company.

The Company covenants and agrees with each Underwriter as follows:

a) Compliance with Securities Regulations and Commission Requests. The Company, subject to Section 3(b), will comply with the requirements of Rule 430B under the Securities Act, and will promptly notify the Representatives, and confirm the notice in writing, of (i) the effectiveness during the Prospectus Delivery Period (as defined below) of any post-effective amendment to the Registration Statement or the filing of any supplement or amendment to the Preliminary Prospectus or the Prospectus, (ii) the receipt of any comments from the Commission during the Prospectus Delivery Period, (iii) any request by the Commission for any amendment to the Registration Statement or any amendment or supplement to the Preliminary Prospectus or the Prospectus or for additional information, and (iv) the issuance by the Commission of any stop order suspending the effectiveness of the Registration Statement or of any order preventing or suspending the use of the Preliminary Prospectus or the Prospectus, or of the suspension of the qualification of the Notes for offering or sale in any jurisdiction, or of the initiation or threatening of any proceedings for any of such purposes. The Company will promptly effect the filings necessary pursuant to Rule 424 and will take such steps as it deems necessary to ascertain promptly whether the Preliminary Prospectus and the Prospectus transmitted for filing under Rule 424 were received for filing by the Commission and, in the event that any of them was not, it will promptly file such document. The Company will use its reasonable best efforts to prevent the issuance of any stop order referred to above and, if any such stop order is issued, to obtain the lifting thereof at the earliest possible moment.

b) Filing of Amendments. During such period beginning on the date of this Agreement and ending on the later of the Closing Date or such date as, in the opinion of counsel for the Underwriters, the Prospectus is no longer required by law to be delivered in connection with sales of the Notes by an Underwriter or dealer, including in circumstances where such requirement may be satisfied pursuant to Rule 172 of the Securities Act (the “Prospectus Delivery Period”), the Company will give the Representatives notice of its intention to file or prepare any amendment to the Registration Statement (including any filing under Rule 462(b) of the Securities Act), or any amendment, supplement or revision to the Disclosure Package or the Prospectus, whether pursuant to the Securities Act, the Exchange Act or otherwise, will furnish the Representatives with copies of any such documents a reasonable amount of time prior to such proposed filing or use, as the case may be, and will not file or use any such document to which the Representatives or counsel for the Underwriters shall reasonably object.

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c) Delivery of Registration Statements. The Company has furnished or will deliver upon request to the Representatives and counsel for the Underwriters, without charge, copies of the signed copies of the Registration Statement as originally filed and of each amendment thereto (including exhibits filed therewith or incorporated by reference therein and documents incorporated or deemed to be incorporated by reference therein) upon request and copies of the signed copies of all consents and certificates of experts, and will also deliver to the Representatives, without charge, a conformed copy of the Registration Statement as originally filed and of each amendment thereto (without exhibits) for each of the Underwriters. The Registration Statement and each amendment thereto furnished upon request to the Underwriters will be identical to any electronically transmitted copies thereof filed with the Commission pursuant to EDGAR, except to the extent permitted by Regulation S-T.

d) Delivery of Prospectuses. The Company will deliver to each Underwriter, without charge, as many copies of the Preliminary Prospectus as such Underwriter may reasonably request, and the Company hereby consents to the use of such copies for purposes permitted by the Securities Act. The Company will furnish to each Underwriter, without charge, during the Prospectus Delivery Period, such number of copies of the Prospectus as such Underwriter may reasonably request. The Preliminary Prospectus and the Prospectus and any amendments or supplements thereto furnished to the Underwriters will be identical to any electronically transmitted copies thereof filed with the Commission pursuant to EDGAR, except to the extent permitted by Regulation S-T.

e) Continued Compliance with Securities Laws. The Company will comply with the Securities Act and the Exchange Act so as to permit the completion of the distribution of the Notes as contemplated in this Agreement and in the Registration Statement, the Disclosure Package and the Prospectus. If at any time during the Prospectus Delivery Period, any event shall occur or condition shall exist as a result of which it is necessary, in the opinion of counsel for the Underwriters or for the Company, to amend the Registration Statement in order that the Registration Statement will not contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading or to amend or supplement the Disclosure Package or the Prospectus in order that the Disclosure Package or the Prospectus, as the case may be, will not include an untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances existing at the Initial Sale Time or at the time it is delivered or conveyed to a purchaser, not misleading, or if it shall be necessary, in the opinion of either such counsel, at any such time to amend the Registration Statement or amend or supplement the Disclosure Package or the Prospectus in order to comply with the requirements of any applicable federal securities law, the Company will (1) notify the Representatives of any such event, development or condition and (2) promptly prepare and file with the Commission, subject to Section 3(b) hereof, such amendment or supplement as may be necessary to correct such statement or omission or to make the Registration Statement, the Disclosure Package or the Prospectus comply with such law, and the Company will furnish to the Underwriters, without charge, such number of copies of such amendment or supplement as the Underwriters may reasonably request.

f) Blue Sky Compliance. The Company shall use their reasonable best efforts to (i) cooperate with the Representatives and counsel for the Underwriters to qualify or register (or obtain exemptions from qualifying or registering) all or any part of the Notes for offer and sale under the state securities or blue sky laws of those jurisdictions designated by the Representatives, (ii) comply with such laws and (iii) continue such qualifications, registrations and exemptions in effect so long as required for the distribution of the Notes.

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The Company shall not be required to qualify as a foreign corporation or to take any action that would subject it to general service of process in any such jurisdiction where it is not presently qualified or where it would be subject to taxation as a foreign corporation. The Company will advise the Representatives promptly of the suspension of the qualification or registration of (or any such exemption relating to) the Notes for offering, sale or trading in any jurisdiction or any initiation or threat of any proceeding for any such purpose, and in the event of the issuance of any order suspending such qualification, registration or exemption, the Company shall use its reasonable best efforts to obtain the withdrawal thereof at the earliest possible moment.

g) Use of Proceeds. The Company shall apply the net proceeds from the sale of the Notes sold by it in the manner described under the caption “Use of Proceeds” in the Preliminary Prospectus and the Prospectus.

h) Depositary. The Company will cooperate with the Underwriters and use its reasonable best efforts to permit the Notes to be eligible for clearance and settlement through the facilities of the Depositary.

i) Periodic Reporting Obligations. During the Prospectus Delivery Period, the Company shall file, on a timely basis, with the Commission and the New York Stock Exchange (“NYSE”) all reports and documents required to be filed under the Exchange Act.

j) Agreement Not to Offer or Sell Additional Notes. During the period commencing on the date hereof and ending on the Closing Date, the Company will not, without the prior written consent of the Representatives (which consent may be withheld at the sole discretion of the Representatives), directly or indirectly, sell, offer, contract or grant any option to sell, pledge, transfer or establish an open “put equivalent position” within the meaning of Rule 16a-1(h) under the Exchange Act, or otherwise dispose of or transfer, or announce the offering of, or file any registration statement under the Securities Act in respect of, any debt securities of the Company similar to the Notes or securities exchangeable for or convertible into debt securities similar to the Notes (other than as contemplated by this Agreement with respect to the Notes).

k) Final Term Sheet. The Company will prepare a final term sheet in a form approved by the Underwriters and attached as Exhibit B, and will file such term sheet pursuant to Rule 433(d) under the Securities Act within the time required by such rule (such term sheet, the “Final Term Sheet”). Any such Final Term Sheet is an Issuer Free Writing Prospectus for purposes of this Agreement.

l) Permitted Free Writing Prospectuses. The Company represents that it has not made, and agrees that, unless it obtains the prior written consent of the Representatives, it will not make, any offer relating to the Notes that would constitute an Issuer Free Writing Prospectus or that would otherwise constitute a “free writing prospectus” (as defined in Rule 405 of the Securities Act) required to be filed by the Company with the Commission or retained by the Company under Rule 433 of the Securities Act; provided that the prior written consent of the Representatives shall be deemed to have been given in respect of any Issuer Free Writing Prospectuses included in Annex I to this Agreement. Any such free writing prospectus consented to or deemed to be consented to by the Representatives is hereinafter referred to as a “Permitted Free Writing Prospectus.” The Company agrees that (i) it has treated and will treat, as the case may be, each Permitted Free Writing Prospectus as an Issuer Free Writing Prospectus, and (ii) has complied and will comply, as the case may be, with the requirements of Rules 164 and 433 of the Securities Act applicable to any Permitted Free Writing Prospectus, including in respect of timely filing with the Commission, legending and record keeping.

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The Company consents to the use by any Underwriter of a free writing prospectus that (a) is not an “issuer free writing prospectus” as defined in Rule 433, and (b) contains only (i) information describing the preliminary terms of the Notes or their offering, (ii) information permitted by Rule 134 under the Securities Act or (iii) information that describes the final terms of the Notes or their offering and that is included in the Final Term Sheet of the Company contemplated in Section 3(k).

m) Registration Statement Renewal Deadline. If immediately prior to the third anniversary (the “Renewal Deadline”) of the initial effective date of the Registration Statement, any of the Notes remain unsold by the Underwriters, the Company will prior to the Renewal Deadline file, if it has not already done so and is eligible to do so, a new automatic shelf registration statement relating to the Notes, in a form satisfactory to the Representatives. If the Company is no longer eligible to file an automatic shelf registration statement, the Company will prior to the Renewal Deadline, if it has not already done so, file a new shelf registration statement relating to the Notes, in a form satisfactory to the Representatives, and will use its reasonable best efforts to cause such registration statement to be declared effective within 60 days after the Renewal Deadline. The Company will take all other action necessary or appropriate to permit the public offering and sale of the Notes to continue as contemplated in the expired registration statement relating to the Notes. References herein to the Registration Statement shall include such new automatic shelf registration statement or such new shelf registration statement, as the case may be.

n) Notice of Inability to Use Automatic Shelf Registration Statement Form. If at any time during the Prospectus Delivery Period, the Company receives from the Commission a notice pursuant to Rule 401(g)(2) or otherwise ceases to be eligible to use the automatic shelf registration statement form, the Company will (i) promptly notify the Representatives, (ii) promptly file a new registration statement or post-effective amendment on the proper form relating to the Notes, in a form satisfactory to the Representatives, (iii) use its best efforts to cause such registration statement or post-effective amendment to be declared effective and (iv) promptly notify the Representatives of such effectiveness. The Company will take all other action necessary or appropriate to permit the public offering and sale of the Notes to continue as contemplated in the registration statement that was the subject of the Rule 401(g)(2) notice or for which the Company has otherwise become ineligible. References herein to the Registration Statement shall include such new registration statement or post-effective amendment, as the case may be.

o) Filing Fees. The Company agrees to pay the required Commission filing fees relating to the Notes within the time required by and in accordance with Rules 456(b)(1) and 457(r) under the Securities Act.

p) Compliance with Sarbanes-Oxley Act. During the Prospectus Delivery Period, the Company will comply in all material respects with all applicable securities and other laws, rules and regulations, including, without limitation, the Sarbanes-Oxley Act, and use its reasonable best efforts to cause the directors and officers of the Company in their capacities as such, to comply with such laws, rules and regulations, including, without limitation, the provisions of the Sarbanes-Oxley Act.

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q) No Manipulation of Price. The Company will not take, directly or indirectly, any action designed to cause or result in, or that has constituted or might reasonably be expected to constitute, under the Exchange Act or otherwise, the stabilization or manipulation of the price of any securities of the Company to facilitate the sale or resale of the Notes.

The Representatives, on behalf of the several Underwriters, may, in their sole discretion, waive in writing the performance by the Company of any one or more of the foregoing covenants or extend the time for their performance.

Section 4. Payment of Expenses. The Company agrees to pay all costs, fees and expenses incurred in connection with the performance of its obligations hereunder and in connection with the transactions contemplated hereby, including without limitation (i) all expenses incidental to the issuance and delivery of the Notes (including all printing and engraving costs), (ii) all necessary issue, transfer and other stamp taxes in connection with the issuance and sale of the Notes, (iii) all fees and expenses of the Company’s counsel, independent public or certified public accountants and other advisors to the Company, (iv) all costs and expenses incurred in connection with the preparation, printing, filing, shipping and distribution of the Registration Statement (including financial statements, exhibits, schedules, consents and certificates of experts), each Issuer Free Writing Prospectus, the Preliminary Prospectus and the Prospectus, and all amendments and supplements thereto, and the Operative Documents, (v) the fees and expenses of the Trustee, including the reasonable fees and expenses of counsel for the Trustee in connection with the Indenture and the Notes, (vi) any fees payable in connection with the rating of the Notes with the ratings agencies, (vii) all fees and expenses (including reasonable fees and expenses of counsel) of the Company in connection with approval of the Notes by the Depositary for “book-entry” transfer, and the performance by the Company of its other obligations under this Agreement, (viii) reasonable and documented expenses incident to the “road show” for the offering of the Notes, (ix) all other fees, costs and expenses referred to in Item 14 of Part II of the Registration Statement, and (x) all other fees, costs and expenses incurred in connection with the performance of its obligations hereunder for which provision is not otherwise made in this Section. Except as provided in this Section 4 and Sections 6, 8 and 9 hereof, the Underwriters shall pay their own expenses, including the fees and disbursements of their counsel.

Section 5. Conditions of the Obligations of the Underwriters. The obligations of the several Underwriters to purchase and pay for the Notes as provided herein on the Closing Date shall be subject to the accuracy of the representations and warranties on the part of the Company set forth in Section 1 hereof as of the date hereof, as of the Initial Sale Time, and as of the Closing Date as though then made and to the timely performance by the Company of its covenants and other obligations hereunder, and to each of the following additional conditions:

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a) Effectiveness of Registration Statement. The Registration Statement shall have become effective under the Securities Act and no stop order suspending the effectiveness of the Registration Statement shall have been issued under the Securities Act and no proceedings for that purpose shall have been instituted or be pending or threatened by the Commission, any request on the part of the Commission for additional information shall have been complied with to the reasonable satisfaction of counsel to the Underwriters and the Company shall not have received from the Commission any notice pursuant to Rule 401(g)(2) of the Securities Act objecting to use of the automatic shelf registration statement form. The Preliminary Prospectus and the Prospectus shall have been filed with the Commission in accordance with Rule 424(b) (or any required post-effective amendment providing such information shall have been filed and declared effective in accordance with the requirements of Rule 430A).

b) Accountants’ Comfort Letter. On the date hereof, the Representatives shall have received from PricewaterhouseCoopers LLP, independent registered public accountants for the Company, a letter dated the date hereof addressed to the Underwriters, in form and substance satisfactory to the Representatives with respect to the audited and unaudited financial statements and certain financial information contained in the Registration Statement, the Preliminary Prospectus and the Prospectus.

c) [Reserved].

d) Bring-down Comfort Letter. On the Closing Date, the Representatives shall have received from PricewaterhouseCoopers LLP, independent registered public accountants for the Company, a letter dated such date, in form and substance satisfactory to the Representatives, to the effect that they reaffirm the statements made in the letter furnished by them pursuant to subsection (b) of this Section 5, except that the specified date referred to therein for the carrying out of procedures shall be no earlier than the date of this Agreement.

e) [Reserved].

f) No Objection. If the Registration Statement and/or the offering of the Notes has been filed with the Financial Industry Regulatory Authority (“FINRA”) for review, the FINRA shall not have raised any objection with respect to the fairness and reasonableness of the underwriting terms and arrangements.

g) No Material Adverse Change or Ratings Agency Change. For the period from and after the date of this Agreement and prior to the Closing Date:

(i) in the judgment of the Representatives there shall not have occurred any Material Adverse Change;

(ii) there shall not have been any change or decrease specified in the letters referred to in paragraph (d) of this Section 5 which is, in the sole judgment of the Representatives, so material and adverse as to make it impractical or inadvisable to proceed with the offering, sale or delivery of the Notes as contemplated by the Prospectus; and

(iii) there shall not have occurred any downgrading, nor shall any notice have been given of any intended or potential downgrading or of any review for a possible change that does not indicate the direction of the possible change, in the rating accorded any securities of the Company or any of its subsidiaries by any “nationally recognized statistical rating organization” as such term is defined in Section 3(a)(62) of the Exchange Act.

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h) Opinion of Counsel for the Company. On the Closing Date, the Representatives shall have received the favorable opinion letter and negative assurance letter of Baker Botts L.L.P., counsel for the Company, dated as of such Closing Date, the form of which is attached as Exhibit A-1.

i) Opinion of Counsel for the Underwriters. On the Closing Date, the Representatives shall have received the favorable opinion letter and negative assurance letter of Davis Polk & Wardwell LLP, counsel for the Underwriters, dated as of such Closing Date, with respect to such matters as may be reasonably requested by the Underwriters.

j) Opinion of In-House Counsel. On the Closing Date, the Representatives shall have received the favorable opinion letter of the general counsel for the Company, dated as of such Closing Date, the form of which is attached as Exhibit A-2.

k) Officers’ Certificate. On the Closing Date, the Representatives shall have received a written certificate executed by the President or a Vice President of the Company and the principal financial or accounting officer of the Company, dated as of such Closing Date, to the effect that:

(i) the Company has received no stop order suspending the effectiveness of the Registration Statement, and no proceedings for such purpose have been instituted or threatened by the Commission;

(ii) the Company has not received from the Commission any notice pursuant to Rule 401(g)(2) of the Securities Act objecting to use of the automatic shelf registration statement form;

(iii) the representations, warranties and covenants of the Company set forth in Section 1 of this Agreement are true and correct with the same force and effect as though expressly made on and as of such Closing Date; and

(iv) the Company has complied with all the agreements hereunder and satisfied all the conditions on its part to be performed or satisfied hereunder at or prior to such Closing Date.

l) [Reserved].

m) Indenture. On the Closing Date, the Company shall have executed and delivered the Supplemental Indenture, in form and substance reasonably satisfactory to the Underwriters, and the Underwriters shall have received executed copies thereof.

n) DTC. The Notes shall be eligible for clearance and settlement through DTC.

o) [Reserved].

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p) Additional Documents. On or before the Closing Date, the Representatives and counsel for the Underwriters shall have received such information, documents and certificates as they may reasonably require for the purposes of enabling them to pass upon the issuance and sale of the Notes as contemplated herein, or in order to evidence the accuracy of any of the representations and warranties, or the satisfaction of any of the conditions or agreements, herein contained.

If any condition specified in this Section 5 is not satisfied when and as required to be satisfied, this Agreement may be terminated by the Representatives by notice to the Company at any time on or prior to the Closing Date, which termination shall be without liability on the part of any party to any other party, except that Sections 4, 6, 8, 9 and 17 shall at all times be effective and shall survive such termination.

Section 6. Reimbursement of Underwriters’ Expenses. If this Agreement is terminated by the Representatives pursuant to Section 5, 10 or 11, or if the sale to the Underwriters of the Notes on the Closing Date is not consummated because of any refusal, inability or failure on the part of the Company to perform any agreement herein or to comply with any provision hereof, the Company agrees to reimburse the Representatives and the other Underwriters (or such Underwriters as have terminated this Agreement with respect to themselves), severally, upon demand for all out-of-pocket expenses that shall have been reasonably incurred by the Representatives and the Underwriters in connection with the proposed purchase and the offering and sale of the Notes, including but not limited to reasonable fees and expenses of counsel, printing expenses, travel expenses, postage, facsimile and telephone charges.

Section 7. Effectiveness of this Agreement. This Agreement shall not become effective until the execution of this Agreement by the parties hereto.

Section 8. Indemnification.

a) Indemnification of the Underwriters. The Company agrees to indemnify and hold harmless each Underwriter, its directors, officers, employees, affiliates and agents, and each person, if any, who controls any Underwriter within the meaning of the Securities Act and the Exchange Act against any loss, claim, damage, liability or expense, as incurred, to which such Underwriter or such director, officer, employee, affiliate, agent or controlling person may become subject, under the Securities Act, the Exchange Act or other federal or state statutory law or regulation, or at common law or otherwise (including in settlement of any litigation, if such settlement is effected with the written consent of the Company), insofar as such loss, claim, damage, liability or expense (or actions in respect thereof as contemplated below) arises out of or is based (i) upon any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement, or any amendment thereto, or the omission or alleged omission therefrom of a material fact required to be stated therein or necessary to make the statements therein not misleading; or (ii) upon any untrue statement or alleged untrue statement of a material fact contained in any Company Additional Written Communication, any Issuer Free Writing Prospectus, the Preliminary Prospectus or the Prospectus (or any amendment or supplement thereto) or any roadshow or investor presentations made to investors by the Company (whether in person or electronically) or the omission or alleged omission therefrom of a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; and to reimburse each Underwriter and each such director, officer, employee, affiliate, agent and controlling person for any and all expenses (including the reasonable fees and expenses of counsel chosen by the Representatives) as such expenses are reasonably incurred by such Underwriter or such director, officer, employee, affiliate, agent or controlling person in connection with investigating, defending, settling, compromising or paying any such loss, claim, damage, liability, expense or action; provided, however, that the foregoing indemnity agreement shall not apply to any loss, claim, damage, liability or expense to the extent, but only to the extent, arising out of or based upon any untrue statement or alleged untrue statement or omission or alleged omission made in reliance upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives expressly for use in the Registration Statement, any Company Additional Written Communication, any Issuer Free Writing Prospectus, the Preliminary Prospectus or the Prospectus (or any amendment or supplement thereto).

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The indemnity agreement set forth in this Section 8(a) shall be in addition to any liabilities that the Company may otherwise have.

b) Indemnification of the Company and its Directors and Officers. Each Underwriter agrees, severally and not jointly, to indemnify and hold harmless the Company, its directors, each of its officers who signed the Registration Statement and each person, if any, who controls the Company within the meaning of the Securities Act or the Exchange Act, against any loss, claim, damage, liability or expense, as incurred, to which the Company or any such director, officer or controlling person may become subject, under the Securities Act, the Exchange Act, or other federal or state statutory law or regulation, or at common law or otherwise (including in settlement of any litigation, if such settlement is effected with the written consent of such Underwriter), insofar as such loss, claim, damage, liability or expense (or actions in respect thereof as contemplated below) arises out of or is based (i) upon any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement, or any amendment thereto, or the omission or alleged omission therefrom of a material fact required to be stated therein or necessary to make the statements therein not misleading; or (ii) upon any untrue statement or alleged untrue statement of a material fact contained in any Company Additional Written Communication, any Issuer Free Writing Prospectus, the Preliminary Prospectus or the Prospectus (or any amendment or supplement thereto) or any roadshow or investor presentations made to investors by the Company (whether in person or electronically) or the omission or alleged omission therefrom of a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading, in each case to the extent, but only to the extent, that such untrue statement or alleged untrue statement or omission or alleged omission was made in the Registration Statement, any Company Additional Written Communication, any Issuer Free Writing Prospectus, the Preliminary Prospectus or the Prospectus (or any amendment or supplement thereto), in reliance upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives expressly for use therein; and to reimburse the Company, or any such director, officer or controlling person for any legal and other expense reasonably incurred by the Company, or any such director, officer or controlling person in connection with investigating, defending, settling, compromising or paying any such loss, claim, damage, liability, expense or action. The Company hereby acknowledges that the only information furnished to the Company by any Underwriter through the Representatives expressly for use in the Registration Statement, any Company Additional Written Communication, any Issuer Free Writing Prospectus, the Preliminary Prospectus or the Prospectus (or any amendment or supplement thereto) or any roadshow or investor presentations made to investors by the Company (whether in person or electronically) are the statements set forth under the caption “Underwriting” in the Preliminary Prospectus and the Prospectus in the seventh paragraph regarding market making activities and in the eleventh paragraph regarding price stabilization.

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The indemnity agreement set forth in this Section 8(b) shall be in addition to any liabilities that each Underwriter may otherwise have.

c) Notifications and Other Indemnification Procedures. Promptly after receipt by an indemnified party under this Section 8 of notice of the commencement of any action, such indemnified party will, if a claim in respect thereof is to be made against an indemnifying party under this Section 8, notify the indemnifying party in writing of the commencement thereof, but the omission to so notify the indemnifying party will not relieve it from any liability which it may have to any indemnified party for contribution or otherwise than under the indemnity agreement contained in this Section 8 or to the extent it is not prejudiced as a proximate result of such failure. In case any such action is brought against any indemnified party and such indemnified party seeks or intends to seek indemnity from an indemnifying party, the indemnifying party will be entitled to participate in, and, to the extent that it shall elect, jointly with all other indemnifying parties similarly notified, by written notice delivered to the indemnified party, to assume the defense thereof with counsel reasonably satisfactory to such indemnified party; provided, however, such indemnified party shall have the right to employ its own counsel in any such action and to participate in the defense thereof, but the fees and expenses of such counsel shall be at the expense of such indemnified party, unless: (i) the employment of such counsel has been specifically authorized in writing by the indemnifying party; (ii) the indemnifying party has failed promptly to assume the defense and employ counsel reasonably satisfactory to the indemnified party; or (iii) the named parties to any such action (including any impleaded parties) include both such indemnified party and the indemnifying party or any affiliate of the indemnifying party, and such indemnified party shall have reasonably concluded that either (x) there may be one or more legal defenses available to it which are different from or additional to those available to the indemnifying party or such affiliate of the indemnifying party or (y) a conflict may exist between such indemnified party and the indemnifying party or such affiliate of the indemnifying party (it being understood, however, that the indemnifying party shall not, in connection with any one such action or separate but substantially similar or related actions in the same jurisdiction arising out of the same general allegations or circumstances, be liable for the reasonable fees and expenses of more than one separate firm of attorneys (in addition to a single firm of local counsel) for all such indemnified parties, which firm, in the case of indemnified parties described in Section 8(a), shall be designated in writing by the Representatives and that all such reasonable fees and expenses shall be reimbursed as they are incurred). Upon receipt of notice from the indemnifying party to such indemnified party of such indemnifying party’s election so to assume the defense of such action and approval by the indemnified party of counsel, the indemnifying party will not be liable to such indemnified party under this Section 8 for any legal or other expenses subsequently incurred by such indemnified party in connection with the defense thereof unless the indemnified party shall have employed separate counsel in accordance with the proviso to the next preceding sentence, in which case the reasonable fees and expenses of counsel shall be at the expense of the indemnifying party.

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d) Settlements. The indemnifying party under this Section 8 shall not be liable for any settlement of any proceeding effected without its written consent, but if settled with such consent or if there be a final judgment for the plaintiff, the indemnifying party agrees to indemnify the indemnified party against any loss, claim, damage, liability or expense by reason of such settlement or judgment. Notwithstanding the foregoing sentence, if at any time an indemnified party shall have requested an indemnifying party to reimburse the indemnified party for fees and expenses of counsel as contemplated by Section 8(c) hereof, the indemnifying party agrees that it shall be liable for any settlement of any proceeding effected without its written consent if (i) such settlement is entered into more than 45 days after receipt by such indemnifying party of the aforesaid request and (ii) such indemnifying party shall not have reimbursed the indemnified party in accordance with such request prior to the date of such settlement. No indemnifying party shall, without the prior written consent of the indemnified party, effect any settlement, compromise or consent to the entry of judgment in any pending or threatened action, suit or proceeding in respect of which any indemnified party is or could have been a party and indemnity was or could have been sought hereunder by such indemnified party, unless such settlement, compromise or consent (i) includes an unconditional release of such indemnified party from all liability on claims that are the subject matter of such action, suit or proceeding and (ii) does not include a statement as to or an admission of fault, culpability or a failure to act by or on behalf of any indemnified party.

Section 9. Contribution. If the indemnification provided for in Section 8 is for any reason held to be unavailable to or otherwise insufficient to hold harmless an indemnified party in respect of any losses, claims, damages, liabilities or expenses referred to therein, then each indemnifying party shall contribute to the aggregate amount paid or payable by such indemnified party, as incurred, as a result of any losses, claims, damages, liabilities or expenses referred to therein (i) in such proportion as is appropriate to reflect the relative benefits received by the Company on the one hand, and the Underwriters, on the other hand, from the offering of the Notes pursuant to this Agreement or (ii) if the allocation provided by clause (i) above is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause (i) above but also the relative fault of the Company on the one hand, and the Underwriters, on the other hand, in connection with the statements or omissions which resulted in such losses, claims, damages, liabilities or expenses, as well as any other relevant equitable considerations. The relative benefits received by the Company on the one hand, and the Underwriters, on the other hand, in connection with the offering of the Notes pursuant to this Agreement shall be deemed to be in the same respective proportions as the total net proceeds from the offering of the Notes pursuant to this Agreement (before deducting expenses) received by the Company, and the total underwriting discount received by the Underwriters bear to the aggregate initial public offering price of the Notes as set forth on such cover. The relative fault of the Company, on the one hand, and the Underwriters, on the other hand, shall be determined by reference to, among other things, whether any such untrue or alleged untrue statement of a material fact or omission or alleged omission to state a material fact relates to information supplied by the Company, on the one hand, or the Underwriters, on the other hand, and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission.

The amount paid or payable by a party as a result of the losses, claims, damages, liabilities and expenses referred to above shall be deemed to include, subject to the limitations set forth in Section 8, any reasonable legal or other fees or expenses reasonably incurred by such party in connection with investigating or defending any action or claim.

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The Company and the Underwriters agree that it would not be just and equitable if contribution pursuant to this Section 9 were determined by pro rata allocation (even if the Underwriters were treated as one entity for such purpose) or by any other method of allocation which does not take account of the equitable considerations referred to in this Section 9.

Notwithstanding the provisions of this Section 9, no Underwriter shall be required to contribute any amount in excess of the underwriting commissions received by such Underwriter in connection with the Notes underwritten by it and distributed to the public. No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The Underwriters’ obligations to contribute pursuant to this Section 9 are several, and not joint, in proportion to their respective underwriting commitments as set forth opposite their names in Schedule A. For purposes of this Section 9, each director, officer, employee, affiliate and agent of an Underwriter and each person, if any, who controls an Underwriter within the meaning of the Securities Act and the Exchange Act shall have the same rights to contribution as such Underwriter, and each director of the Company, each officer of the Company who signed the Registration Statement, and each person, if any, who controls the Company within the meaning of the Securities Act and the Exchange Act shall have the same rights to contribution as the Company.

Section 10. Default of One or More of the Several Underwriters. If, on the Closing Date, any one or more of the several Underwriters shall fail or refuse to purchase Notes that it or they have agreed to purchase hereunder on such date, and the aggregate principal amount of Notes that such defaulting Underwriter or Underwriters agreed but failed or refused to purchase does not exceed 10% of the aggregate principal amount of the Notes to be purchased on such date, the other Underwriters shall be obligated, severally, in the proportion to the principal amount of such Notes set forth opposite their respective names on Schedule A bears to the aggregate principal amount of such Notes set forth opposite the names of all such non-defaulting Underwriters, or in such other proportions as may be specified by the Representatives with the consent of the non-defaulting Underwriters, to purchase such Notes which such defaulting Underwriter or Underwriters agreed but failed or refused to purchase on such date. If, on the Closing Date, any one or more of the Underwriters shall fail or refuse to purchase such Notes and the aggregate principal amount of such Notes with respect to which such default occurs exceeds 10% of the aggregate principal amount of Notes to be purchased on such date, and arrangements satisfactory to the Representatives and the Company for the purchase of such Notes are not made within 48 hours after such default, this Agreement shall terminate without liability of any non-defaulting Underwriter to any other party except that the provisions of Sections 4, 6, 8, 9 and 17 shall at all times be effective and shall survive such termination. In any such case, either the Representatives or the Company shall have the right to postpone the Closing Date, but in no event for longer than seven days in order that the required changes, if any, to the Registration Statement, any Issuer Free Writing Prospectus, the Preliminary Prospectus or the Prospectus or any other documents or arrangements may be effected.

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As used in this Agreement, the term “Underwriter” shall be deemed to include any person substituted for a defaulting Underwriter under this Section 10. Any action taken under this Section 10 shall not relieve any defaulting Underwriter from liability in respect of any default of such Underwriter under this Agreement.

Section 11. Termination of this Agreement. Prior to the Closing Date, this Agreement may be terminated by the Representatives by notice given to the Company if at any time (i) trading or quotation in any of the Company’s securities shall have been suspended or limited by the Commission or the NYSE, or trading in securities generally on either the Nasdaq Stock Market or the NYSE shall have been suspended or limited, or minimum or maximum prices shall have been generally established on any of such stock exchanges by the Commission or the FINRA; (ii) a general banking moratorium shall have been declared by federal, New York banking authorities; (iii) there shall have occurred any outbreak or escalation of national or international hostilities or any crisis or calamity involving the United States, or any change in the United States or international financial markets, or any substantial change or development involving a prospective substantial change in United States’ or international political, financial or economic conditions, as in the judgment of the Representatives is material and adverse and makes it impracticable or inadvisable to market the Notes in the manner and on the terms described in the Disclosure Package or the Prospectus or to enforce contracts for the sale of securities; (iv) in the judgment of the Representatives there shall have occurred any Material Adverse Change; or (v) there shall have occurred a material disruption in commercial banking or securities settlement or clearance services. Any termination pursuant to this Section 11 shall be without liability of any party to any other party except as provided in Sections 4 and 6 hereof, and provided further that Sections 4, 6, 8, 9 and 17 shall survive such termination and remain in full force and effect.

Section 12. No Fiduciary Duty. The Company acknowledges and agrees that: (i) the purchase and sale of the Notes pursuant to this Agreement, including the determination of the public offering price of the Notes and any related discounts and commissions, is an arm’s-length commercial transaction between the Company, on the one hand, and the several Underwriters, on the other hand, and the Company is capable of evaluating and understanding and understands and accepts the terms, risks and conditions of the transactions contemplated by this Agreement; (ii) in connection with each transaction contemplated hereby and the process leading to such transaction each Underwriter is and has been acting solely as a principal and is not the financial advisor, agent or fiduciary of the Company or its affiliates, stockholders, creditors or employees or any other party; (iii) no Underwriter has assumed or will assume an advisory, agency or fiduciary responsibility in favor of the Company with respect to any of the transactions contemplated hereby or the process leading thereto (irrespective of whether such Underwriter has advised or is currently advising the Company on other matters) and no Underwriter has any obligation to the Company with respect to the offering contemplated hereby except the obligations expressly set forth in this Agreement; (iv) the several Underwriters and their respective affiliates may be engaged in a broad range of transactions that involve interests that differ from those of the Company and that the several Underwriters have no obligation to disclose any of such interests by virtue of any advisory, agency or fiduciary relationship; and (v) the Underwriters have not provided any legal, accounting, regulatory or tax advice with respect to the offering contemplated hereby and the Company have consulted their own legal, accounting, regulatory and tax advisors to the extent they deemed appropriate.

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This Agreement supersedes all prior agreements and understandings (whether written or oral) between the Company and the several Underwriters with respect to the subject matter hereof. The Company hereby waives and releases, to the fullest extent permitted by law, any claims that they may have against the several Underwriters with respect to any breach or alleged breach of agency or fiduciary duty.

Section 13. Representations and Indemnities to Survive Delivery. The respective indemnities, agreements, representations, warranties and other statements of the Company, of its officers and of the several Underwriters set forth in or made pursuant to this Agreement (i) will remain operative and in full force and effect, regardless of any (A) investigation, or statement as to the results thereof, made by or on behalf of any Underwriter, the officers or employees of any Underwriter, or any person controlling the Underwriter, the Company, the officers or employees of the Company, or any person controlling the Company, as the case may be or (B) acceptance of the Notes and payment for them hereunder and (ii) will survive delivery of and payment for the Notes sold hereunder and any termination of this Agreement.

Section 14. Notices. All communications hereunder shall be in writing and shall be mailed, e-mailed, hand delivered or telecopied and confirmed to the parties hereto as follows:

If to the Representatives:

BofA Securities, Inc.

114 West 47th Street

NY8-114-07-01

New York, New York 10036

Attention: High Grade Transaction Management/Legal

Fax: (212) 901-7881

Deutsche Bank Securities Inc.

1 Columbus Circle

New York, New York 10019

Attention: Debt Capital Markets Syndicate, with a copy to General Counsel

E-mail: dbcapmarkets.gcnotices@list.db.com)

J.P. Morgan Securities LLC

270 Park Ave

New York, NY 10017

Attention: Investment Grade Syndicate Desk Davis Polk & Wardwell LLP

Fax: (212) 834-6081

Wells Fargo Securities, LLC

550 South Tryon Street, 5th Floor

Charlotte, North Carolina 28202

Attention: Transaction Management

Email: tmgcapitalmarkets@wellsfargo.com

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with a copy to:

450 Lexington Avenue

New York, New York 10017

Attention: Byron B. Rooney and Stephen A. Byeff

E-mail: byron.rooney@davispolk.com, stephen.byeff@davispolk.com

Fax: (212) 701-5658, (212) 701-5715

If to the Company:

Westlake Corporation

2801 Post Oak Boulevard

Houston, Texas 77056

Attention: General Counsel

E-mail: legaldepartment@westlake.com

Fax: (713) 960-9111; (713) 629-6239

with a copy to:

Baker Botts L.L.P.

910 Louisiana Street

Houston, Texas 77002

Attention: Timothy S. Taylor and Carina L. Antweil

E-mail: timothy.taylor@bakerbotts.com; carina.antweil@bakerbotts.com

Fax: (713) 229-7784

Any party hereto may change the address for receipt of communications by giving written notice to the others.

Section 15. Successors. This Agreement will inure to the benefit of and be binding upon the parties hereto, including any substitute Underwriters pursuant to Section 10 hereof, and to the benefit of the directors, officers, employees, affiliates, agents and controlling persons referred to in Sections 8 and 9, and in each case their respective successors, and no other person will have any right or obligation hereunder. The term “successors” shall not include any purchaser of the Notes as such from any of the Underwriters merely by reason of such purchase.

Section 16. Partial Unenforceability. The invalidity or unenforceability of any Section, paragraph or provision of this Agreement shall not affect the validity or enforceability of any other Section, paragraph or provision hereof. If any Section, paragraph or provision of this Agreement is for any reason determined to be invalid or unenforceable, there shall be deemed to be made such minor changes (and only such minor changes) as are necessary to make it valid and enforceable.

Section 17. Governing Law Provisions. THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE INTERNAL LAWS OF THE STATE OF NEW YORK APPLICABLE TO AGREEMENTS MADE AND TO BE PERFORMED IN THAT STATE.

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Section 18. Consent to Jurisdiction. Any legal suit, action or proceeding arising out of or based upon this Agreement or the transactions contemplated hereby (“Related Proceedings”) may be instituted in the federal courts of the United States of America located in the City and County of New York, Borough of Manhattan, or the courts of the State of New York in each case located in the City and County of New York, Borough of Manhattan (collectively, the “Specified Courts”), and each party irrevocably submits to the exclusive jurisdiction (except for proceedings instituted in regard to the enforcement of a judgment of any such court (a “Related Judgment”), as to which such jurisdiction is non-exclusive) of such courts in any such suit, action or proceeding. Service of any process, summons, notice or document by mail to such party’s address set forth above shall be effective service of process for any suit, action or other proceeding brought in any such court. The parties irrevocably and unconditionally waive any objection to the laying of venue of any suit, action or other proceeding in the Specified Courts and irrevocably and unconditionally waive and agree not to plead or claim in any such court that any such suit, action or other proceeding brought in any such court has been brought in an inconvenient forum.

Section 19. Research Analyst Independence. The Company acknowledges that the Underwriters’ research analysts and research departments are required to be independent from their respective investment banking divisions and are subject to certain regulations and internal policies, and that such Underwriters’ research analysts may hold views and make statements or investment recommendations and/or publish research reports with respect to the Company, its subsidiaries and/or the offering of the Notes that differ from the views of their respective investment banking divisions. The Company hereby waives and releases, to the fullest extent permitted by applicable law, any claims that the Company may have against the Underwriters with respect to any conflict of interest that may arise from the fact that the views expressed by their independent research analysts and research departments may be different from or inconsistent with the views or advice communicated to the Company by such Underwriters’ investment banking divisions. The Company acknowledges that each of the Underwriters is a full service securities firm and as such from time to time, subject to applicable securities laws, may effect transactions for its own account or the account of its customers and hold long or short positions in debt or equity securities of the companies that may be the subject of the transactions contemplated by this Agreement.

Section 20. Waiver of Jury Trial. The Company hereby irrevocably waives, to the fullest extent permitted by applicable law, any and all right to trial by jury in any legal proceeding arising out of or relating to this Agreement or the transactions contemplated hereby.

Section 21. General Provisions. This Agreement may be executed in two or more counterparts, each one of which shall be an original, with the same effect as if the signatures thereto and hereto were upon the same instrument. This Agreement may not be amended or modified unless in writing by all of the parties hereto, and no condition herein (express or implied) may be waived unless waived in writing by each party whom the condition is meant to benefit. The Section headings herein are for the convenience of the parties only and shall not affect the construction or interpretation of this Agreement.

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The use of electronic signatures and electronic records (including, without limitation, any contract or other record created, generated, sent, communicated, received, or stored by electronic means) shall be of the same legal effect, validity and enforceability as a manually executed signature or use of a paper-based record-keeping system to the fullest extent permitted by applicable law, including the Federal Electronic Signatures in Global and National Commerce Act, the New York State Electronic Signatures and Records Act and any other applicable law, including, without limitation, any state law based on the Uniform Electronic Transactions Act or the Uniform Commercial Code.

Each of the parties hereto acknowledges that it is a sophisticated business person who was adequately represented by counsel during negotiations regarding the provisions hereof, including, without limitation, the indemnification provisions of Section 8 and the contribution provisions of Section 9, and is fully informed regarding said provisions. Each of the parties hereto further acknowledges that the provisions of Sections 8 and 9 hereto fairly allocate the risks in light of the ability of the parties to investigate the Company, its affairs and its business in order to assure that adequate disclosure has been made in the Registration Statement, the Disclosure Package and the Prospectus (and any amendments and supplements thereto), as required by the Securities Act and the Exchange Act.

Section 22. Recognition of the U.S. Special Resolution Regimes.

a) In the event that any Underwriter that is a Covered Entity becomes subject to a proceeding under a U.S. Special Resolution Regime, the transfer from such Underwriter of this Agreement, and any interest and obligation in or under this Agreement, will be effective to the same extent as the transfer would be effective under the U.S. Special Resolution Regime if this Agreement, and any such interest and obligation, were governed by the laws of the United States or a state of the United States.

b) In the event that any Underwriter that is a Covered Entity or a BHC Act Affiliate of such Underwriter becomes subject to a proceeding under a U.S. Special Resolution Regime, Default Rights under this Agreement that may be exercised against such Underwriter are permitted to be exercised to no greater extent than such Default Rights could be exercised under the U.S. Special Resolution Regime if this Agreement were governed by the laws of the United States or a state of the United States.

*   *   *

“BHC Act Affiliate” has the meaning assigned to the term “affiliate” in, and shall be interpreted in accordance with, 12 U.S.C. § 1841(k).

“Covered Entity” means any of the following:

a “covered entity” as that term is defined in, and interpreted in accordance with, 12 C.F.R. § 252.82(b);

a “covered bank” as that term is defined in, and interpreted in accordance with, 12 C.F.R. § 47.3(b); or

a “covered FSI” as that term is defined in, and interpreted in accordance with, 12 C.F.R. § 382.2(b).

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“Default Right” has the meaning assigned to that term in, and shall be interpreted in accordance with, 12 C.F.R. §§ 252.81, 47.2 or 382.1, as applicable.

“U.S. Special Resolution Regime” means each of (i) the Federal Deposit Insurance Act and the regulations promulgated thereunder and (ii) Title II of the Dodd-Frank Wall Street Reform and Consumer Protection Act and the regulations promulgated thereunder.

[Signature Pages Follow]

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If the foregoing is in accordance with your understanding of our agreement, kindly sign and return to the Company the enclosed copies hereof, whereupon this instrument, along with all counterparts hereof, shall become a binding agreement in accordance with its terms.

[Signature Page to Underwriting Agreement]

The foregoing Underwriting Agreement is hereby confirmed and accepted by the Representatives as of the date first above written.

[Signature Page to Underwriting Agreement]

The foregoing Underwriting Agreement is hereby confirmed and accepted by the Representatives as of the date first above written.

[Signature Page to Underwriting Agreement]

The foregoing Underwriting Agreement is hereby confirmed and accepted by the Representatives as of the date first above written.

[Signature Page to Underwriting Agreement]

The foregoing Underwriting Agreement is hereby confirmed and accepted by the Representatives as of the date first above written.

[Signature Page to Underwriting Agreement]

SCHEDULE A

Sch-A

ANNEX I

Issuer Free Writing Prospectuses

Final Term Sheet dated November 4, 2025

Annex-I

ANNEX II

Company Additional Written Communication

Electronic (Netroadshow) road show of the Company used in connection the offering of the Notes on November 3, 2025 and November 4, 2025 Form of Opinion of In-House Counsel

Annex-II

EXHIBIT A-1

Form of Opinion of Baker Botts L.L.P.

A-1

EXHIBIT A-2

A-2-1

EXHIBIT B

Final Pricing Term Sheet

Filed Pursuant to Rule 433

Registration No. 333-291208

Free Writing Prospectus

(To Prospectus dated October 31, 2025 and

Preliminary Prospectus Supplement dated November 4, 2025)

$1,200,000,000

Westlake Corporation

$600,000,000 5.550% Senior Notes due 2035

$600,000,000 6.375% Senior Notes due 2055

Final Term Sheet

November 4, 2025

B-1

* None of these ratings is a recommendation to buy, sell or hold these securities. Each rating may be subject to revision or withdrawal at any time, and should be evaluated independently of any other rating.

** It is expected that delivery of the notes will be made against payment therefor on or about November 6, 2025, which is the second business day following the date hereof (such settlement cycle being referred to as “T+2”). Under Rule 15c6-1 under the Securities Exchange Act of 1934, as amended, trades in the secondary market generally are required to settle in one business day unless the parties to any such trade expressly agree otherwise. Accordingly, purchasers who wish to trade the notes on any date prior to the business day before delivery will be required, by virtue of the fact that the notes initially will settle in T+2, to specify an alternative settlement cycle at the time of any such trade to prevent failed settlement and should consult their own advisors.

The Issuer has filed a registration statement (including a prospectus) with the Securities and Exchange Commission (the “SEC”) for the offering to which this communication relates. Before you invest, you should read the prospectus in that registration statement and other documents the Issuer has filed with the SEC for more complete information about the Issuer and this offering. You may get these documents for free by visiting EDGAR on the SEC’s website at www.sec.gov. Alternatively, the Issuer or any underwriter participating in this offering can arrange to send you the prospectus supplement and accompanying prospectus if you request it by contacting BofA Securities, Inc. at 1-800-294-1322; Deutsche Bank Securities Inc. at 1-800-503-4611; J.P. Morgan Securities LLC collect at 1-212-834-5433 or Wells Fargo Securities, LLC at 1-800-645-3751.

This pricing term sheet supplements and, to the extent inconsistent, supersedes the preliminary form of prospectus supplement filed with the SEC by the Issuer on November 4, 2025 (the “Prospectus Supplement”) relating to the Prospectus dated October 31, 2025. All capitalized terms used in this term sheet shall have the meaning ascribed to them in the Prospectus Supplement.

Any disclaimer or other notice that may appear below is not applicable to this communication and should be disregarded. Such disclaimer or notice was automatically generated as a result of this communication being sent by Bloomberg or another email system.

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Exhibit 4.2

Execution Version

WESTLAKE CORPORATION

5.550% Senior Notes due 2035

6.375% Senior Notes due 2055

Fifteenth Supplemental Indenture

Dated as of November 6, 2025

THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A.

Trustee

TABLE OF CONTENTS

i

FIFTEENTH SUPPLEMENTAL INDENTURE dated as of November 6, 2025 (this “Supplemental Indenture”), to the Indenture dated as of January 1, 2006 (the “Indenture”), by and among WESTLAKE CORPORATION, a Delaware corporation (the “Company”), each of the potential guarantors named therein and THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A. (as successor to JPMorgan Chase Bank, National Association), as trustee (the “Trustee”).

Each party agrees as follows for the benefit of the other parties and for the equal and ratable benefit of the Holders (as defined herein):

WHEREAS, the Company and the Trustee have duly authorized the execution and delivery of the Indenture to provide for the issuance from time to time of the Company’s debentures, notes, bonds or other evidences of indebtedness to be issued in one or more series as in the Indenture provided (as defined therein, “Securities”);

WHEREAS, the Company desires and has requested the Trustee to join it in the execution and delivery of this Supplemental Indenture in order to establish and provide for the issuance by the Company of two series of Securities designated as its 5.550% Senior Notes due 2035, substantially in the form attached hereto as Exhibit A (the “2035 Notes”) and 6.375% Senior Notes due 2055, substantially in the form attached hereto as Exhibit B (the “2055 Notes” and, together with the 2035 Notes, the “Notes”), in each case on the terms set forth herein;

WHEREAS, Section 2.01 of the Indenture provides that a supplemental indenture may be entered into by the Company and the Trustee for such purpose provided certain conditions are met;

WHEREAS, the conditions set forth in the Indenture for the execution and delivery of this Supplemental Indenture have been complied with; and

WHEREAS, all things necessary to make this Supplemental Indenture a valid agreement of the Company and the Trustee, in accordance with its terms, and a valid amendment of, and supplement to, the Indenture have been done;

NOW, THEREFORE:

In consideration of the premises and the purchase and acceptance of the Notes by the Holders thereof, the Company covenants and agrees with the Trustee, for the equal and ratable benefit of the Holders, that the Indenture is supplemented and amended, to the extent expressed herein, as follows:

ARTICLE ONE

Scope of Supplemental Indenture; General

The changes, modifications and supplements to the Indenture effected by this Supplemental Indenture shall be applicable only with respect to, and govern the terms of, the Notes, which shall not be limited in aggregate principal amount, and shall not apply to any other Securities that may be issued under the Indenture unless a supplemental indenture with respect to such other Securities specifically incorporates such changes, modifications and supplements.

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Pursuant to this Supplemental Indenture, there is hereby created and designated two series of Securities under the Indenture entitled “5.550% Senior Notes due 2035” and “6.375% Senior Notes due 2055.” The 2035 Notes shall be in the form of Exhibit A hereto, which is hereby incorporated into this Supplemental Indenture by reference. The 2055 Notes shall be in the form of Exhibit B hereto, which is hereby incorporated into this Supplemental Indenture by reference.

ARTICLE TWO

Certain Definitions

The following terms have the meanings set forth below in this Supplemental Indenture. Capitalized terms used but not defined herein have the meanings ascribed to such terms in the Indenture. To the extent terms defined herein differ from the Indenture the terms defined herein will govern.

“2035 Notes” has the meaning provided in the Recitals.

“2055 Notes” has the meaning provided in the Recitals.

“2035 Par Call Date” has the meaning provided in new Section 3.12(b) of the Indenture.

“2055 Par Call Date” has the meaning provided in new Section 3.12(b) of the Indenture.

“Applicable FATCA Law” has the meaning provided in Section 6.14.

“Attributable Debt” means, as to any lease in respect of a Sale and Leaseback Transaction under which any Person is at the time liable, at any date as of which the amount thereof is to be determined, the total net amount of rent required to be paid by such Person under such lease during the remaining term thereof (or, if earlier, the first date upon which such lease may be terminated without penalty), discounted from the respective due dates thereof to such date at the weighted average rate per annum borne by the Notes, compounded annually. The net amount of rent required to be paid under any such lease for any such period shall be the aggregate amount of the rent payable by the lessee with respect to such period after excluding amounts required to be paid on account of maintenance and repairs, insurance, taxes, assessments, water rates and similar charges. Unless the Company elects to calculate the total amount of rent required to be paid through the first date upon which such lease may be terminated without penalty (if such a provision exists), in the case of any lease which is terminable by the lessee upon the payment of a penalty, such net amount shall also include the amount of such penalty, but no rent shall be considered as required to be paid under such lease subsequent to the first date upon which it may be so terminated.

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“Below Investment Grade Rating Event” with respect to the Notes of either series means the rating on the Notes of such series is lowered and as a result the Notes of such series cease to be rated Investment Grade by each of the Rating Agencies on any date during the period (the “Trigger Period”) commencing on the earlier of (a) the occurrence of a Change of Control and (b) the first public announcement by the Company of any Change of Control (or pending Change of Control) and ending 60 days following the consummation of such Change of Control (which Trigger Period will be extended if the rating of the Notes of such series is under publicly announced consideration for possible downgrade by any Rating Agency on such 60th day, such extension to last with respect to each Rating Agency until the date on which such Rating Agency considering such possible downgrade either (x) rates the Notes of such series below Investment Grade or (y) publicly announces that it is no longer considering the Notes of such series for possible downgrade; provided that no such extension will occur if on such 60th day the Notes of such series are rated Investment Grade not subject to review for possible downgrade by any Rating Agency); provided that a rating event will not be deemed to have occurred in respect of a particular Change of Control (and thus will not be deemed a Below Investment Grade Rating Event for purposes of the definition of Change of Control Triggering Event contained in this Article Two) if each Rating Agency making the reduction in rating does not publicly announce or confirm or inform the Trustee in writing at the Company’s request that the reduction was the result, in whole or in part, of any event or circumstance comprised of or arising as a result of, or in respect of, the Change of Control (whether or not the applicable Change of Control has occurred at the time of the Below Investment Grade Rating Event). If any Rating Agency withdraws its rating on the Notes of such series or otherwise ceases to provide a rating on the Notes of such series on any day during the Trigger Period for any reason and the Company has not selected a replacement Rating Agency pursuant to the terms of this Supplemental Indenture, the rating of such Rating Agency shall be deemed to be rated below Investment Grade on such day.

“Beneficial Owner” has the meaning assigned to such term in Rule 13d-3 and Rule 13d-5 under the Exchange Act, except that in calculating the beneficial ownership of any particular “person” as such term is used in Section 13(d)(3) of the Exchange Act, such “person” will be deemed to have beneficial ownership of all securities that such “person” has the right to acquire by conversion or exercise of other securities, whether such right is currently exercisable or is exercisable only upon the occurrence of a subsequent condition.

“Business Day” means any day that is not a Saturday, a Sunday or a day on which banking institutions in any of New York, New York, Houston, Texas or a place of payment on the Notes is authorized or obligated by law, regulation or executive order to remain closed.

“Capital Stock” means:

(1) in the case of a corporation, capital stock;

(2) in the case of an association or business entity, any and all shares, interests, participations, rights or other equivalents (however designated) of capital stock;

(3) in the case of a partnership or limited liability company, partnership interests (whether general or limited) or membership interests, respectively; and

(4) any other interest or participation that confers on a Person the right to receive a share of the profits and losses of, or distributions of assets of, the issuing Person, but excluding from all of the foregoing any debt securities convertible into Capital Stock, whether or not such debt securities include any right of participation with Capital Stock.

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“Change of Control” means the occurrence of any of the following after the date of this Supplemental Indenture:

(1) the direct or indirect sale, lease, transfer, conveyance or other disposition (other than by way of merger or consolidation), in one or a series of related transactions, of all or substantially all of the assets of the Company and the Subsidiaries taken as a whole to any “person” or “group” (as those terms are used in Section 13(d)(3) of the Exchange Act) other than to the Company or a Subsidiary;

(2) the consummation of any transaction (including, without limitation, any merger or consolidation) the result of which is that any “person” or “group” (as those terms are used in Section 13(d)(3) of the Exchange Act, it being agreed that an employee of the Company or any Subsidiary for whom shares are held under an employee stock ownership, employee retirement, employee savings or similar plan and whose shares are voted in accordance with the instructions of such employee shall not be a member of a “group” (as that term is used in Section 13(d)(3) of the Exchange Act) solely because such employee’s shares are held by a trustee under said plan) becomes the ultimate Beneficial Owner, directly or indirectly, of Voting Stock of the Company representing more than 50% of the voting power of the outstanding Voting Stock of the Company;

(3) the Company consolidates with, or merges with or into, any Person, or any Person consolidates with, or merges with or into, the Company, in any such event pursuant to a transaction in which any of the outstanding Voting Stock of the Company or Voting Stock of such other Person is converted into or exchanged for cash, securities or other property, other than any such transaction where the Voting Stock of the Company outstanding immediately prior to such transaction constitutes, or is converted into or exchanged for, Voting Stock representing more than 50% of the voting power of the Voting Stock of the surviving Person or its parent immediately after giving effect to such transaction;

(4) during any period of 24 consecutive calendar months, the majority of the members of the Board of Directors of the Company shall no longer be composed of individuals (a) who were members of the Board of Directors of the Company on the first day of such period or (b) whose election or nomination to the Board of Directors of the Company was approved by individuals referred to in clause (a) above constituting, at the time of such election or nomination, at least a majority of the Board of Directors of the Company or, if directors are nominated by a committee of the Board of Directors of the Company, constituting at the time of such nomination, at least a majority of such committee; or

(5) the adoption of a plan relating to the liquidation or dissolution of the Company.

Notwithstanding the foregoing, a transaction will not be deemed to involve a Change of Control if (i) the Company becomes a direct or indirect wholly owned subsidiary of a holding company and (ii) the direct or indirect holders of the Voting Stock of such holding company immediately following that transaction are substantially the same as the holders of the Voting Stock in the Company immediately prior to that transaction.

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“Change of Control Offer” has the meaning provided in new Section 4.10(a) of the Indenture.

“Change of Control Payment” has the meaning provided in new Section 4.10(a) of the Indenture.

“Change of Control Payment Date” has the meaning provided in new Section 4.10(b) of the Indenture.

“Change of Control Triggering Event” with respect to the Notes of either series means the occurrence of both a Change of Control and a Below Investment Grade Rating Event. Notwithstanding the foregoing, no Change of Control Triggering Event will be deemed to have occurred in connection with any particular Change of Control unless and until such Change of Control has actually been consummated.

“Code” means the Internal Revenue Code of 1986, as amended.

“Company” has the meaning provided in the Indenture.

“Consolidated Net Tangible Assets” means the aggregate amount of assets (less operating leases, applicable reserves and other properly deductible items) after deducting therefrom (a) all current liabilities, except for (i) notes and loans payable, (ii) current maturities of long-term debt and (iii) current maturities of obligations under finance leases and operating leases and (b) all goodwill, trade names, trademarks, patents, unamortized debt discount and expense, turnaround costs and other like intangibles, all as set forth on the most recent balance sheet of the Company and its consolidated Subsidiaries and computed in accordance with GAAP. Deferred income taxes, deferred investment tax credit or other similar items, as calculated in accordance with GAAP, will not be considered as a liability or as a deduction from or adjustment to total assets.

“Debt” has the meaning provided in new Section 4.08 of the Indenture.

“Electronic Means” means the following communications methods: e-mail, secure electronic transmission containing applicable authorization codes, passwords and/or authentication keys issued by the Trustee, or another method or system specified by the Trustee as available for use in connection with its services hereunder.

“Fair Market Value” means the price that could be negotiated in an arm’s-length transaction between a willing buyer and a willing seller not involving distress or necessity of either party, determined in good faith by the Board of Directors of the Company.

“Fitch” means Fitch Ratings, Inc. or any successor to the rating agency business thereof.

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“Funded Debt” means all indebtedness for money borrowed having a maturity of more than 12 months from the date of the most recent balance sheet of the Company and its consolidated Subsidiaries or having a maturity of less than 12 months but by its terms being renewable or extendible beyond 12 months from the date of such balance sheet at the option of the borrower of such indebtedness.

“H.15” has the meaning provided in new Section 3.12 of the Indenture.

“H.15 TCM” has the meaning provided in new Section 3.12 of the Indenture.

“Holder” means the Person in whose name a Note is registered in the books of the Registrar for the Notes.

“Indenture” has the meaning provided in the Preamble.

“Investment Grade” means a rating of BBB- or better by Fitch (or its equivalent under any successor rating category of Fitch), a rating of Baa3 or better by Moody’s (or its equivalent under any successor rating category of Moody’s) and a rating of BBB- or better by S&P (or its equivalent under any successor rating category of S&P), and the equivalent investment grade credit rating from any replacement rating agency or rating agencies selected by the Company under the circumstances specified in this Supplemental Indenture permitting the Company to select a replacement rating agency and in the manner specified in this Supplemental Indenture for selecting a replacement rating agency, in each case as set forth in the definition of “Rating Agency.”

“Moody’s” means Moody’s Investors Service, Inc., a subsidiary of Moody’s Corporation, and its successors.

“Mortgage” and “Mortgages” have the meanings provided in new Section 4.08 of the Indenture.

“Notes” has the meaning provided in the Recitals.

“Par Call Date” has the meaning provided in new Section 3.12(b) of the Indenture.

“Paying Agent” means The Bank of New York Mellon Trust Company, N.A. or any successor paying agent.

“Person” means any individual, corporation, limited liability company, partnership, joint venture, association, joint stock company, trust, estate, unincorporated organization or government or any agency or political subdivision thereof or any other entity.

“Principal Property” means any single parcel of real estate, any single manufacturing plant or any single warehouse owned or leased in connection with a Sale and Leaseback Transaction by the Company or any Subsidiary which is located within the United States and the net book value of which on the date as of which the determination is being made exceeds 1% of Consolidated Net Tangible Assets, other than any such manufacturing plant or warehouse or portion thereof (a) which is a pollution control or other facility financed by obligations issued by a state or local government unit and described in Sections 141(a), 142(a)(5), 142(a)(6), 142(a)(10) or 144(a) of the Code (or their successor provisions) or by any other obligations the interest of which is excluded under Section 103 of the Code (or its successor provision), or (b) which, in the good-faith opinion of the Board of Directors of the Company, as evidenced by a Board Resolution, is not of material importance to the total business conducted by the Company and the Subsidiaries taken as a whole.

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“Rating Agency” means each of Fitch, Moody’s and S&P; provided that if any of Fitch, Moody’s or S&P ceases to provide rating services to issuers or investors, the Company may appoint another “nationally recognized statistical rating organization” (as defined under the Exchange Act) as a replacement for such Rating Agency; provided that the Company shall give written notice of such appointment to the Trustee.

“Registrar” means The Bank of New York Mellon Trust Company, N.A., or any successor registrar of the Notes.

“Remaining Life” has the meaning provided in new Section 3.12 of the Indenture.

“Remaining Scheduled Payments” means the remaining scheduled payments of the principal of and interest on each Note to be redeemed that would be due after the related Redemption Date but for such redemption.

“Restricted Subsidiary” means a wholly owned Subsidiary of the Company, substantially all of the assets of which are located in the United States (excluding territories or possessions), and which owns a Principal Property; provided, however, that the term Restricted Subsidiary shall not include any Subsidiary that is principally engaged in (a) the business of financing; (b) the business of owning, buying, selling, leasing, dealing in or developing real property; or (c) the business of exporting goods or merchandise from or importing goods or merchandise into the United States.

“S&P” means S&P Global Ratings, a division of S&P Global Inc., and its successors.

“Sale and Leaseback Transaction” has the meaning provided in new Section 4.09 of the Indenture.

“Secured Debt” has the meaning provided in new Section 4.08 of the Indenture.

“Subsidiary” means a Person more than 50% of the outstanding Voting Stock of which is owned, directly or indirectly, by the Company or by one or more other Subsidiaries, or by the Company and one or more other Subsidiaries.

“Supplemental Indenture” has the meaning provided in the Preamble.

“Treasury Rate” has the meaning provided in new Section 3.12 of the Indenture.

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“Trigger Period” has the meaning provided in the definition of “Below Investment Grade Rating Event.”

“Trustee” has the meaning provided in the Preamble.

“Voting Stock” of any specified Person as of any date means the capital stock (or comparable equity interests) of such Person that is at the time entitled to vote generally in the election of the board of directors (or members of the governing body) of such Person.

ARTICLE THREE

Redemption

Section 3.01. Selection of Securities To Be Redeemed.

Section 3.03 of the Indenture shall be amended by replacing that section of the Indenture with the following, but only with respect to the Notes:

If less than all of the Notes of either series are to be redeemed, the particular Notes of such series to be redeemed shall be selected not more than 60 days prior to the Redemption Date by the Trustee from the outstanding Notes of such series not previously called for redemption, by lot; provided that, if at the time of redemption such Notes are registered as a Global Security, the Depositary shall determine, in accordance with its procedures, the principal amount of such Notes held by each Beneficial Owner of Notes to be redeemed. Notes may be selected for redemption in principal amounts of $1,000 and integral multiples of $1,000 in excess thereof, provided that the unredeemed portion of a Note must be in a minimum principal amount of $2,000.

The Trustee shall promptly notify the Company and the Registrar in writing of the Notes of either series selected for redemption and, in the case of any Notes of such series selected for partial redemption, the principal amount thereof to be redeemed. For purposes of this Indenture, unless the context otherwise requires, all provisions relating to redemption of Notes of such series shall relate, in the case of any of the Notes of such series redeemed or to be redeemed only in part, to the portion of the principal amount thereof which has been or is to be redeemed.

Section 3.02. Notice of Redemption.

Section 3.04 of the Indenture shall be amended by replacing that section of the Indenture with the following, but only with respect to the Notes:

Notice of redemption shall be sent not less than 10 days nor more than 60 days prior to the Redemption Date, to each Holder of Securities to be redeemed, at the address of such Holder appearing in the register of Securities maintained by the Registrar.

Notice of any redemption of the Notes in connection with a corporate transaction that is pending (including an equity offering, an incurrence of Debt or a change of control) may, at the Company’s discretion, be given subject to one or more conditions precedent, including, but not limited to, completion of the transaction. If such redemption is so subject to satisfaction of one or more conditions precedent, such notice shall describe each such condition, and such notice may be rescinded in the event that any or all such conditions shall not have been satisfied or otherwise waived by the Redemption Date.

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The Company shall notify holders of Notes called for redemption of any such rescission as soon as practicable after the Company determines that such conditions precedent will not be able to be satisfied or the Company is not able or willing to waive such conditions precedent.

All notices of redemption shall identify the Securities to be redeemed and shall state:

(1) the Redemption Date;

(2) the Redemption Price (or the method of calculating or determining the Redemption Price);

(3) that, unless the Company defaults in making the redemption payment, interest on Securities called for redemption ceases to accrue on and after the Redemption Date, and the only remaining right of the Holders of such Securities is to receive payment of the Redemption Price upon surrender to the Paying Agent of the Securities redeemed;

(4) if any Security is to be redeemed in part, the portion of the principal amount thereof to be redeemed and that on and after the Redemption Date, upon surrender for cancellation of such Security to the Paying Agent, a new Security or Securities in the aggregate principal amount equal to the unredeemed portion thereof will be issued without charge to the Holder;

(5) that Securities called for redemption must be surrendered to the Paying Agent to collect the Redemption Price and the name and address of the Paying Agent;

(6) that the redemption is for a sinking or analogous fund, if such is the case;

(7) if such Securities are convertible into or exchangeable for capital stock, other debt securities (including Securities), warrants, other equity securities or any other securities or property of the Company or any other Person, the name and address of the conversion or exchange agent, the date on which the right to convert or exchange is terminated and the conversion or exchange rate; and

(8) the CUSIP number, if any, relating to such Securities.

Notice of redemption of Securities to be redeemed at the election of the Company shall be given by the Company or, at the Company’s written request, given to the Trustee at least 5 days before the notice of redemption is delivered to the Holders (unless the Trustee agrees to a shorter period), by the Trustee in the name and at the expense of the Company.

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Section 3.03. Effect of Notice of Redemption.

Section 3.05 of the Indenture shall be amended by replacing that section of the Indenture with the following, but only with respect to the Notes:

Once notice of redemption is sent, subject to the satisfaction of any conditions precedent provided in the notice of redemption, Securities called for redemption become due and payable on the Redemption Date and at the Redemption Price. Upon surrender to the Paying Agent, such Securities called for redemption shall be paid at the Redemption Price, but interest installments whose maturity is on or prior to such Redemption Date will be payable on the relevant Interest Payment Dates to the Holders of record at the close of business on the relevant record dates specified pursuant to Section 2.01.

Section 3.04. Redemption at the Option of the Company.

The following Section 3.12 shall be added to Article III of the Indenture, but only with respect to the Notes:

SECTION 3.12. Redemption at the Option of the Company.

(a) Prior to (i) August 15, 2035 in the case of the 2035 Notes (three months prior to the Stated Maturity of the 2035 Notes) (the “2035 Par Call Date”) and (ii) May 15, 2055 in the case of the 2055 Notes (six months prior to the Stated Maturity of the 2055 Notes) (the “2055 Par Call Date”; the 2035 Par Call Date and the 2055 Par Call Date are each a “Par Call Date”), the Company may redeem the 2035 Notes or the 2055 Notes, respectively, at its option, in whole or in part, at any time and from time to time, at a Redemption Price (expressed as a percentage of principal amount and rounded to three decimal places) equal to the greater of:

(i) (a) the sum of the present values of the Remaining Scheduled Payments on the Notes of such series to be redeemed discounted to the Redemption Date (assuming the Notes to be redeemed matured on the applicable Par Call Date) on a semi-annual basis (assuming a 360-day year consisting of twelve 30-day months) at the applicable Treasury Rate plus 25 basis points in the case of the 2035 Notes and 30 basis points in the case of the 2055 Notes, less (b) interest accrued to the Redemption Date; and

(ii) 100% of the principal amount of the Notes of such series to be redeemed;

plus, in either case, accrued and unpaid interest thereon to, but not including, the Redemption Date.

On or after the 2035 Par Call Date, in the case of the 2035 Notes, or the 2055 Par Call Date, in the case of the 2055 Notes, the Company may redeem the 2035 Notes or the 2055 Notes, respectively, in whole or in part, at any time and from time to time, at a redemption price equal to 100% of the principal amount of the Notes being redeemed plus, in each case, accrued and unpaid interest thereon to, but not including, the Redemption Date.

“Treasury Rate” means, with respect to any Redemption Date, the yield determined by the Company in accordance with the following two paragraphs.

The Treasury Rate shall be determined by the Company after 4:15 p.m., New York City time (or after such time as yields on U.S. government securities are posted daily by the Board of Governors of the Federal Reserve System), on the third Business Day preceding the Redemption Date based upon the yield or yields for the most recent day that appear after such time on such day in the most recent statistical release published by the Board of Governors of the Federal Reserve System designated as “Selected Interest Rates (Daily) - H.15” (or any successor designation or publication) (“H.15”) under the caption “U.S.

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government securities–Treasury constant maturities–Nominal” (or any successor caption or heading) (“H.15 TCM”). In determining the Treasury Rate, the Company shall select, as applicable: (1) the yield for the Treasury constant maturity on H.15 exactly equal to the period from the Redemption Date to the applicable Par Call Date (the “Remaining Life”); or (2) if there is no such Treasury constant maturity on H.15 exactly equal to the Remaining Life, the two yields – one yield corresponding to the Treasury constant maturity on H.15 immediately shorter than and one yield corresponding to the Treasury constant maturity on H.15 immediately longer than the Remaining Life – and shall interpolate to the applicable Par Call Date on a straight-line basis (using the actual number of days) using such yields and rounding the result to three decimal places; or (3) if there is no such Treasury constant maturity on H.15 shorter than or longer than the Remaining Life, the yield for the single Treasury constant maturity on H.15 closest to the Remaining Life. For purposes of this paragraph, the applicable Treasury constant maturity or maturities on H.15 shall be deemed to have a maturity date equal to the relevant number of months or years, as applicable, of such Treasury constant maturity from the Redemption Date.

If on the third Business Day preceding the Redemption Date H.15 TCM is no longer published, the Company shall calculate the Treasury Rate based on the rate per annum equal to the semi-annual equivalent yield to maturity at 11:00 a.m., New York City time, on the second Business Day preceding such Redemption Date of the United States Treasury security maturing on, or with a maturity that is closest to, the applicable Par Call Date, as applicable. If there is no United States Treasury security maturing on the applicable Par Call Date but there are two or more United States Treasury securities with a maturity date equally distant from the applicable Par Call Date, one with a maturity date preceding the applicable Par Call Date and one with a maturity date following the applicable Par Call Date, the Company shall select the United States Treasury security with a maturity date preceding the applicable Par Call Date. If there are two or more United States Treasury securities maturing on the applicable Par Call Date or two or more United States Treasury securities meeting the criteria of the preceding sentence, the Company shall select from among these two or more United States Treasury securities the United States Treasury security that is trading closest to par based upon the average of the bid and asked prices for such United States Treasury securities at 11:00 a.m., New York City time. In determining the Treasury Rate in accordance with the terms of this paragraph, the semi-annual yield to maturity of the applicable United States Treasury security shall be based upon the average of the bid and asked prices (expressed as a percentage of principal amount) at 11:00 a.m., New York City time, of such United States Treasury security, and rounded to three decimal places.

(b) The Company’s actions and determinations in determining the Redemption Price shall be conclusive and binding for all purposes, absent manifest error. The Trustee shall have no responsibility to calculate or determine the Redemption Price of the Treasury Rate.

(c) The Company may at any time, and from time to time, purchase the Notes of either series at any price or prices in the open market, through negotiated transactions, by tender offer or otherwise.

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(d) The Company shall have no obligation to make mandatory redemption of the Notes or to redeem, purchase or repay Notes pursuant to any sinking fund or analogous provision or, except as provided in Section 4.10, at the option of a Holder thereof.

(e) With respect to any redemption occurring prior to the applicable Par Call Date, the Company shall deliver notice to the Trustee of the related Redemption Price promptly after the calculation thereof and the Trustee shall not have any responsibility for such calculation.

ARTICLE FOUR

Covenants

The following covenants shall be added to Article IV of the Indenture for the benefit of Holders, but only with respect to the Notes:

Section 4.08. Restrictions on Secured Debt.

The Company shall not, and the Company shall not permit any Restricted Subsidiary to, incur, issue, assume or guarantee any notes, bonds, debentures or other similar evidences of indebtedness for money borrowed (“Debt”), secured by pledge of, or mortgage or lien on, any Principal Property, or any shares of Capital Stock of or Debt of any Restricted Subsidiary (such pledges, mortgages and liens being called “Mortgage” or “Mortgages” and such Debt secured by such Mortgages being called “Secured Debt”), without effectively providing that the Notes (together with, if the Company shall so determine, any other indebtedness of the Company or such Restricted Subsidiary then existing or thereafter created which is not subordinate to the Notes) shall be secured equally and ratably with (or prior to) such Secured Debt, so long as such Secured Debt shall be so secured, unless after giving effect thereto, the aggregate amount of all such Secured Debt plus all Attributable Debt of the Company and its Restricted Subsidiaries in respect of any Sale and Leaseback Transaction would not, at the time of such incurrence, issuance, assumption or guarantee, exceed 15% of Consolidated Net Tangible Assets; provided, however, that this restriction shall not apply to, and there shall be excluded from Secured Debt in any computation under such restriction, indebtedness secured by:

(a) Mortgages on such property or shares of Capital Stock or Debt existing on the date of this Supplemental Indenture;

(b) Mortgages on such property or shares of Capital Stock of or Debt of any Person, which Mortgages are existing at the time (i) such Person became a Restricted Subsidiary, (ii) such Person is merged into or consolidated with the Company or any Subsidiary or (iii) the Company or a Subsidiary merges into or consolidates with such Person (in a transaction in which such Person becomes a Restricted Subsidiary), which Mortgage was not incurred in anticipation of such transaction and was outstanding prior to such transaction;

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(c) Mortgages in favor of the Company; (d) Mortgages in favor of a governmental entity or in favor of the holders of securities issued by any such entity, pursuant to any contract or statute (including Mortgages to secure debt of the pollution control or industrial revenue bond type) or to secure any indebtedness incurred for the purpose of financing all or any part of the purchase price or the cost of construction of the property subject to such Mortgages;

(e) Mortgages in favor of any governmental entity to secure progress, advance or other payments pursuant to any contract or provision of any statute;

(f) Mortgages on such property or shares of Capital Stock or Debt existing at the time of acquisition thereof (including acquisition through merger or consolidation);

(g) Mortgages on such property or shares of Capital Stock or Debt to secure the payment of all or any part of the purchase price or construction cost thereof or to secure any Debt incurred prior to, at the time of, or within 180 days after, the acquisition of such property or shares or Debt, the completion of any construction or the commencement of full operation, for the purpose of financing all or any part of the purchase price or construction cost thereof;

(h) Mortgages incurred in connection with a Sale and Leaseback Transaction satisfying the provisions set forth in Section 4.09; and

(i) any extension, renewal or replacement (or successive extensions, renewals or replacements), as a whole or in part, of any Mortgage referred to in the foregoing clauses; provided that such extension, renewal or replacement Mortgage shall be limited to all or a part of the same such property or shares of Capital Stock or Debt that secured the Mortgage extended, renewed or replaced (plus improvements on such property).

Section 4.09. Limitations on Sale and Leaseback Transactions.

The Company shall not, and shall not permit any Restricted Subsidiary to, enter into any arrangement with any bank, insurance company or other lender or investor (not including the Company or any Restricted Subsidiary) or to which any such lender or investor is a party, providing for the leasing by the Company or a Restricted Subsidiary for a period, including renewals, in excess of three years of any Principal Property the ownership of which has been or is to be sold or transferred, more than 180 days after the completion of construction and commencement of full operation thereof, by the Company or such Restricted Subsidiary to such lender or investor or to any Person to whom funds have been or are to be advanced by such lender or investor on the security of such Principal Property (referred to as a “Sale and Leaseback Transaction”) unless:

(a) such Sale and Leaseback Transaction is with a governmental entity that provides financial or tax benefits;

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(b) the Company or such Restricted Subsidiary could create Secured Debt pursuant to the provisions set forth in Section 4.08 on the Principal Property to be leased in an amount equal to the Attributable Debt with respect to such Sale and Leaseback Transaction without equally and ratably securing the Notes; or (c) the net proceeds of the sale or transfer of the Principal Property leased pursuant to such Sale and Leaseback Transaction is at least equal to the Fair Market Value of such Principal Property and within 180 days after such sale or transfer shall have been made by the Company or by a Restricted Subsidiary, the Company shall apply an amount not less than the greater of (i) the net proceeds of the sale of the Principal Property leased pursuant to such arrangement or (ii) the Fair Market Value of the Principal Property so leased at the time of entering into such arrangement (as evidenced by an Officers’ Certificate delivered to the Trustee) to the retirement of Funded Debt of the Company; provided that the amount to be applied to the retirement of Funded Debt of the Company shall be reduced by (x) the principal amount of Notes delivered within 180 days after such sale to the Trustee for retirement and cancellation, and (y) the principal amount of Funded Debt other than Notes, voluntarily retired by the Company within 180 days after such sale. No retirement referred to in this clause (c) may be effected by payment at maturity or pursuant to any mandatory sinking fund payment or mandatory prepayment provision.

Section 4.10. Change of Control Triggering Event.

(a) Upon the occurrence of a Change of Control Triggering Event, unless the Company, subject to Section 4.10(d), has exercised its right to redeem the Notes of either series in accordance with Section 3.12, each Holder of the Notes of such series will have the right to require the Company to purchase all or a portion ($1,000 or an integral multiple of $1,000 in excess thereof) of such Holder’s Notes of such series pursuant to the offer described below (the “Change of Control Offer”), at a purchase price equal to 101% of the principal amount thereof plus accrued and unpaid interest, if any, to, but not including, the date of purchase (the “Change of Control Payment”), subject to the rights of Holders of the Notes of such series on the relevant record date to receive interest due on the relevant Interest Payment Date; provided that the principal amount of a Note of such series remaining outstanding after a repurchase in part shall be $2,000 or an integral multiple of $1,000 in excess thereof.

(b) Within 30 days following the date upon which the Change of Control Triggering Event occurred, or at the Company’s option, prior to any Change of Control but after the public announcement of the pending Change of Control, the Company shall deliver a notice to each Holder of Notes that were not redeemed, with a copy to the Trustee, which notice shall govern the terms of the Change of Control Offer. Such notice will, among other things, state the purchase date, which must be no earlier than 30 days nor later than 60 days from the date such notice is sent, other than as may be required by applicable law (the “Change of Control Payment Date”), describe the transaction or transactions constituting the Change of Control Triggering Event and offer to repurchase the Notes. The notice, if sent prior to the date of consummation of the Change of Control, shall state that the Change of Control Offer is conditioned on the Change of Control being consummated on or prior to the Change of Control Payment Date.

(c) On the Change of Control Payment Date, the Company shall, to the extent lawful:

(i) accept or cause a third party to accept for payment all Notes or portions of Notes properly tendered pursuant to the Change of Control Offer; (ii) deposit or cause a third party to deposit with the Paying Agent an amount equal to the Change of Control Payment in respect of all Notes or portions of Notes properly tendered; and

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(iii) deliver or cause to be delivered to the Trustee the Notes to be redeemed properly accepted together with an Officers’ Certificate stating the aggregate principal amount of Notes or portions of Notes being repurchased and that all conditions precedent to the Change of Control Offer and to the repurchase by the Company of Notes pursuant to the Change of Control Offer have been complied with.

(d) The Company will not be required to make a Change of Control Offer with respect to the Notes of either series if (i) a third party makes such an offer in the manner, at the times and otherwise in compliance with the requirements for such an offer otherwise required to be made by the Company and such third party purchases all such Notes of such series properly tendered and not withdrawn under its offer or (ii) a notice of redemption has been given to the Holders of all of the Notes of such series in accordance with the terms of the Indenture, unless and until there is a default in payment of the Redemption Price.

(e) A Change of Control Offer may be made in advance of a Change of Control, conditional upon such Change of Control, if a definitive agreement is in place with respect to the Change of Control at the time of making of the Change of Control Offer.

(f) The Company will comply in all material respects with the requirements of Rule 14e-1 under the Exchange Act, and any other securities laws and regulations thereunder to the extent those laws and regulations are applicable in connection with the repurchase of the Notes as a result of a Change of Control Triggering Event. To the extent that the provisions of any such securities laws or regulations conflict with this Section 4.10, the Company will comply with those securities laws and regulations and will not be deemed to have breached its obligations under this Section 4.10 by virtue of any such conflict.

ARTICLE FIVE

Trustee

Section 5.01. Notice of Defaults.

Section 7.05 of the Indenture shall be amended by replacing that section of the Indenture with the following, but only with respect to the Notes:

If a Default or Event of Default with respect to the Securities of any series occurs and is continuing and the Trustee is notified in writing of such default or event of default, the Trustee shall send to Holders of Securities of such series a notice of the Default or Event of Default within 90 days after receiving such notice. Except in the case of a Default or Event of Default in payment of principal of, premium (if any) and interest on and Additional Amounts or any sinking fund installment with respect to the Securities of such series, the Trustee may withhold the notice if and so long as a committee of its Responsible Officers in good faith determines that withholding the notice is in the interests of Holders of Securities of such series.

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ARTICLE SIX

Miscellaneous

Section 6.01. Electronic Signature.

The words “execution,” “executed,” “signed,” “signature,” and words of like import in this Supplemental Indenture shall include images of manually executed signatures transmitted by facsimile, email or other electronic format (including, without limitation, “pdf,” “tif” or “jpg”) and other electronic signatures (including without limitation, DocuSign and AdobeSign). The use of electronic signatures and electronic records (including, without limitation, any contract or other record created, generated, sent, communicated, received or stored by electronic means) shall be of the same legal effect, validity and enforceability as a manually executed signature or use of a paper-based record-keeping system to the fullest extent permitted by applicable law, including the Federal Electronic Signatures in Global and National Commerce Act, the New York State Electronic Signatures and Records Act and any other applicable law, including, without limitation, any state law based on the Uniform Electronic Transactions Act or the Uniform Commercial Code. Without limitation to the foregoing, and anything in this Supplemental Indenture to the contrary notwithstanding, (a) any Officers’ Certificate, Company Order, Opinion of Counsel, Security, certificate of authentication appearing on or attached to any Security or other certificate, opinion of counsel, instrument, agreement or other document delivered pursuant to this Supplemental Indenture may be executed, attested and transmitted by any of the foregoing electronic means and formats and (b) all references in Section 2.04 or elsewhere in the Indenture to the execution or authentication of any Security or any certificate of authentication appearing on or attached to any Security by means of a manual or facsimile signature shall be deemed to include signatures that are made or transmitted by any of the foregoing electronic means or formats.

Section 6.02. No Recourse Against Others.

Section 11.08 of the Indenture shall be amended by replacing that section of the Indenture with the following, but only with respect to the Notes:

A director, officer, member, manager, employee, stockholder, partner or other owner of the Company or the Trustee, as such, shall not have any liability for any obligations of the Company under the Notes or for any obligations of the Company or the Trustee under this Indenture or for any claim based on, in respect of or by reason of such obligations or their creation. Each Holder by accepting a Note waives and releases all such liability. The waiver and release shall be part of the consideration for the issuance of Notes.

Section 6.03. Governing Law.

The laws of the State of New York shall govern this Supplemental Indenture and the Notes.

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Section 6.04. No Adverse Interpretation of Other Agreements.

This Supplemental Indenture may not be used to interpret another indenture (other than the Indenture), loan or debt agreement of the Company. Any such indenture, loan or debt agreement may not be used to interpret this Supplemental Indenture.

Section 6.05. Successors and Assigns.

All covenants and agreements of the Company in this Supplemental Indenture and the Notes shall bind its successors and assigns. All agreements of the Trustee in this Supplemental Indenture shall bind its successors and assigns.

Section 6.06. Duplicate Originals.

The parties may sign any number of copies of this Supplemental Indenture. Each signed copy shall be an original, but all of them together represent the same agreement.

Section 6.07. Severability.

In case any provision in this Supplemental Indenture or in the Notes shall be invalid, illegal or unenforceable, the validity, legality and enforceability of the remaining provisions shall, to the fullest extent permitted by applicable law, not in any way be affected or impaired thereby.

Section 6.08. Amendments to the Indenture Applicable to the Notes Only.

(a) With respect to the Notes only, Section 11.07 of the Indenture is amended and restated in its entirety, and shall be read as follows:

SECTION 11.07. Business Days.

If the principal of or any premium or interest on the Notes is payable on a day that is not a Business Day, the payment will be made on the following Business Day, and no interest shall accrue for the intervening period.

(b) Section 9.01 of the Indenture is supplemented with the addition of the following with respect to the Notes:

(12) to provide any other modifications which do not adversely affect the interests of the Holders in any material respect; and

(13) to conform the provisions of the Indenture or the Notes to the “Description of the Senior Notes” section of the final prospectus supplement relating to the Notes, dated November 4, 2025.

Section 6.09. Rights of Trustee.

In no event shall the Trustee be responsible or liable for special, indirect, punitive or consequential loss or damage of any kind whatsoever (including, but not limited to, loss of profit) irrespective of whether the Trustee has been advised of the likelihood of such loss or damage and regardless of the form of action.

17

The Trustee may request that the Company deliver an Officers’ Certificate setting forth the names of individuals and/or titles of officers (with specimen signatures) authorized at such times to take specific actions pursuant to this Supplemental Indenture, which Officers’ Certificate may be signed by any person specified as so authorized in any such certificate previously delivered and not superseded.

Section 6.10. Waiver of Jury Trial.

Each of the Company and the Trustee hereby irrevocably waives, to the fullest extent permitted by applicable law, any and all right to trial by jury in any legal proceeding arising out of or relating to this Supplemental Indenture, the Indenture, the Notes or the transactions contemplated hereby.

Section 6.11. Force Majeure.

In no event shall the Trustee be responsible or liable for any failure or delay in the performance of its obligations under this Supplemental Indenture arising out of or caused by, directly or indirectly, forces beyond its reasonable control, including, without limitation, strikes, work stoppages, accidents, acts of war or terrorism, civil or military disturbances, nuclear or natural catastrophes or acts of God, and interruptions, loss or malfunctions of utilities, communications or computer (software or hardware) services.

Section 6.12. No Recitals, etc.

The Trustee shall not be responsible in any manner whatsoever for or in respect of the validity or sufficiency of this Supplemental Indenture or for or in respect of the recitals contained herein, all of which are made solely by the Company.

Section 6.13. Notices.

The Trustee shall have the right to accept and act upon instructions, including funds transfer instructions (for the purposes of this Section, “Instructions”) given pursuant to the Indenture and delivered using Electronic Means; provided, however, that the Company shall provide to the Trustee an incumbency certificate listing authorized officers and containing specimen signatures of such authorized officers, which incumbency certificate shall be amended by the Company whenever a person is to be added or deleted from the listing. If the Company elects to give the Trustee Instructions using Electronic Means and the Trustee in its discretion elects to act upon such Instructions, the Trustee’s understanding of such Instructions shall be deemed controlling. The Company understands and agrees that the Trustee cannot determine the identity of the actual sender of such Instructions and that the Trustee shall conclusively presume that directions that purport to have been sent by an authorized officer listed on the incumbency certificate provided to the Trustee have been sent by such authorized officer. The Company shall be responsible for ensuring that only authorized officers transmit such Instructions to the Trustee and that the Company and all authorized officers are solely responsible to safeguard the use and confidentiality of applicable user and authorization codes, passwords and/or authentication keys upon receipt by the Company.

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The Trustee shall not be liable for any losses, costs or expenses arising directly or indirectly from the Trustee’s reliance upon and compliance with such Instructions notwithstanding such Instructions conflict or are inconsistent with a subsequent written instruction. The Company agrees: (i) to assume all risks arising out of the use of Electronic Means to submit Instructions to the Trustee, including without limitation the risk of the Trustee acting on unauthorized Instructions, and the risk of interception and misuse by third parties; (ii) that it is fully informed of the protections and risks associated with the various methods of transmitting Instructions to the Trustee and that there may be more secure methods of transmitting Instructions than the method(s) selected by the Company; (iii) that the security procedures (if any) to be followed in connection with its transmission of Instructions provide to it a commercially reasonable degree of protection in light of its particular needs and circumstances; and (iv) to notify the Trustee immediately upon learning of any compromise or unauthorized use of the security procedures.

Section 6.14. Foreign Account Tax Compliance Act.

Each of the Company and the Trustee agrees to provide the other with such information in its possession (subject in all cases to applicable privacy laws) as reasonably requested by the other to enable the determination of whether any payment to a Holder pursuant to the Indenture is subject to withholding imposed pursuant to Sections 1471 through 1474 of the Code, any regulations thereunder, intergovernmental agreements in respect thereof or official interpretations of any of the foregoing (“Applicable FATCA Law”). The Trustee shall be entitled to make any withholding or deduction from payments under the Notes or this Indenture to the extent necessary (in the Trustee’s reasonable judgment) to comply with Applicable FATCA Law, for which the Trustee shall not have any liability.

Section 6.15. Submission To Jurisdiction.

The Company hereby irrevocably submits to the jurisdiction of any New York State court sitting in the Borough of Manhattan in the City of New York or any federal court sitting in the Southern District in the Borough of Manhattan in the City of New York in respect of any suit, action or proceeding arising out of or relating to this Indenture and the Notes, and irrevocably accepts for itself and in respect of its property, generally and unconditionally, jurisdiction of the aforesaid courts.

Section 6.16. Economic Sanctions.

The Company represents that neither it nor any of its affiliates, subsidiaries, directors or officers are the target or subject of any sanctions enforced by the U.S. Government (including, without limitation, the Office of Foreign Assets Control of the U.S. Department of the Treasury or the U.S. Department of State), the United Nations Security Council, the European Union, His Majesty’s Treasury, or other relevant sanctions authority (collectively “Sanctions”).

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The Company covenants that neither it nor any of its affiliates, subsidiaries, directors or officers will directly or indirectly use any payments made pursuant to this Indenture, (i) to fund or facilitate any activities of or business with any person who, at the time of such funding or facilitation, is the subject or target of Sanctions, (ii) to fund or facilitate any activities of or business with any country or territory that is the target or subject of Sanctions, or (iii) in any other manner that will result in a violation of Sanctions by any person.

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SIGNATURES

IN WITNESS WHEREOF, the parties have caused this Supplemental Indenture to be duly executed, all as of the date first above written.

[Signature Page to Fifteenth Supplemental Indenture]

[Signature Page to Fifteenth Supplemental Indenture]

EXHIBIT A

FORM

OF

5.550% SENIOR NOTE DUE 2035

A-1

[FORM OF FACE OF NOTE]

Global Notes Legend

[THIS NOTE IS A GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF THE DEPOSITORY TRUST COMPANY (570 WASHINGTON BOULEVARD, JERSEY CITY, NEW JERSEY) OR OTHER DULY APPOINTED DEPOSITORY (THE “DEPOSITARY”) OR THEIR RESPECTIVE NOMINEES. UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE OR IN PART FOR NOTES IN CERTIFICATED FORM, THIS NOTE MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITARY TO A NOMINEE OF THE DEPOSITARY OR BY A NOMINEE OF THE DEPOSITARY TO THE DEPOSITARY OR ANOTHER NOMINEE OF THE DEPOSITARY OR BY THE DEPOSITARY OR ANY SUCH NOMINEE TO A SUCCESSOR DEPOSITARY OR A NOMINEE OF SUCH SUCCESSOR DEPOSITARY.

UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION, TO THE ISSUER HEREOF OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY (AND ANY PAYMENT IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY), ANY TRANSFER, PLEDGE, OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.]

WESTLAKE CORPORATION

5.550% SENIOR NOTE DUE 2035

A-2

WESTLAKE CORPORATION, a corporation duly organized and existing under the laws of the State of Delaware (herein called the “Company,” which term includes any successor under the Indenture referred to below), for value received, hereby promises to pay to __________________, or its registered assigns, the principal sum of _____________________ ($________________) on the Stated Maturity shown above (or upon any earlier date of redemption or acceleration of maturity) (each such date being hereinafter referred to as the “Maturity Date”) and to pay interest thereon, from and including the immediately preceding Interest Payment Date to which interest has been paid or duly provided for (or from, and including, the Original Issue Date if no interest has been paid or duly provided for), to, but excluding, the Maturity Date, semi-annually in arrears on each Interest Payment Date as specified above, commencing on May 15, 2026 at the rate per annum shown above until the principal hereof is paid or made available for payment and at such rate on any overdue principal and on any overdue installment of interest. Capitalized terms used herein shall have the meanings specified in the Indenture.

Reference is hereby made to the further provisions of this Note set forth on the reverse hereof, which provisions shall for all purposes have the same force and effect as if set forth on the face hereof.

Unless the Certificate of Authentication hereon has been executed by the Trustee, this Note shall not be entitled to any benefit under the Indenture or be valid or obligatory for any purpose.

A-3

IN WITNESS WHEREOF, the Company has caused this instrument to be duly executed.

A-4

CERTIFICATE OF AUTHENTICATION

This is one of the Securities of the series designated therein referred to in the within-mentioned Indenture.

Date of Authentication: ________________, 20__

THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A., as Trustee

A-5

[REVERSE OF NOTE]

Westlake Corporation

5.550% Senior Note due 2035

This Note is one of a duly authorized issue of 5.550% Senior Notes due 2035 (the “Notes”) of Westlake Corporation, a Delaware corporation (the “Company”). Capitalized terms used herein shall have the meanings specified in the Indenture (as defined below).

1. Interest.

The Company promises to pay interest on the principal amount of this Note at the rate per annum shown above. The Company shall pay such interest semi-annually in arrears on May 15 and November 15 of each year, commencing May 15, 2026. Interest will be paid on each such Interest Payment Date to the Persons who are registered Holders of the Notes at the close of business on the May 1 or November 1 (whether or not a Business Day) next preceding the Interest Payment Date (each such date, a “Regular Record Date”), even if such Interest Payment Date is a Redemption Date, Change of Control Payment Date or other Maturity Date, except as provided in Section 2.14 of the Indenture with respect to defaulted interest. Interest on the Notes will accrue from the most recent date to which interest has been paid or duly provided for or, if no interest has been paid or duly provided for, from November 6, 2025. Interest will be computed on the basis of a 360-day year of twelve 30-day months.

2. Method of Payment.

Upon the terms and subject to the conditions of the Indenture, the Company will make all payments of the Redemption Price and Change of Control Payment and principal due at Maturity in respect of the Notes to Holders who surrender such Notes to a Paying Agent to collect such payments; provided that if any Redemption Date, Change of Control Payment Date or other Maturity Date is an Interest Payment Date, accrued and unpaid interest shall be paid to the Holder as of the immediately preceding Regular Record Date. The Company will pay all amounts due in respect of the Notes in money of the United States of America that at the time of payment is legal tender for payment of public and private debts. The Company will make such payments (i) by wire transfer of immediately available funds to any account maintained in the United States with respect to Notes evidenced by Global Securities and any other Notes with any aggregate principal amount in excess of $1,000,000 the Holder of which has provided wire transfer instructions to the Paying Agent at least five Business Days prior to the applicable payment date or (ii) by check payable in such money mailed to a Holder’s registered address with respect to any certificated Notes.

3. Paying Agent and Registrar.

Initially, The Bank of New York Mellon Trust Company, N.A., the Trustee under the Indenture, will act as Paying Agent and Registrar at its office at 601 Travis Street, 16th Floor, Houston, Texas 77002. The Company may appoint and change any Paying Agent or Registrar without notice to any Holder. The Company or any of its Subsidiaries may act as Paying Agent or Registrar.

A-6

4. Indenture.

The Company issued the Notes under an Indenture dated as of January 1, 2006 (the “Base Indenture”), as supplemented by the Fifteenth Supplemental Indenture dated as of November 6, 2025 (the “Fifteenth Supplemental Indenture,” and together with the Base Indenture, the “Indenture”) between the Company and the Trustee. The terms of the Notes include those stated in the Indenture and those made part of the Indenture by reference to the Trust Indenture Act of 1939, as amended (the “TIA”). The Notes are subject to all such terms, and Holders are referred to the Indenture and the TIA for a statement of such terms. To the extent any provision of this Note conflicts with the express provisions of the Indenture, the provisions of the Indenture shall govern and be controlling. The Notes are general unsecured obligations of the Company and are initially issued in an aggregate principal amount of $600,000,000. The Company may, subject to the provisions of the Indenture, issue additional Notes of the same series as the Notes from time to time without the consent of the Holders. The Notes initially issued and any additional Notes subsequently issued under the Indenture will be treated as a single series for all purposes of the Indenture, including, without limitation, with respect to waivers, amendments, supplements, redemptions and offers to purchase, provided that if any such additional Notes are not fungible with the Notes initially issued for United States federal income tax purposes, such additional Notes will have one or more separate CUSIP numbers from the Notes initially issued. The Indenture provides for the issuance of other series of debt securities (including the Notes, the “Securities”) thereunder.

5. Optional Redemption.

Prior to August 15, 2035 (three months prior to the Stated Maturity of the Notes) (the “Par Call Date”), the Company may redeem the Notes at its option, in whole or in part, at any time and from time to time, at a Redemption Price equal to the greater of:

(i) (a) the sum of the present values of the Remaining Scheduled Payments on the Notes to be redeemed discounted to the Redemption Date (assuming the Notes to be redeemed matured on the Par Call Date) on a semi-annual basis (assuming a 360-day year consisting of twelve 30-day months) at the Treasury Rate plus 25 basis points, less (b) interest accrued to the Redemption Date; and

(ii) 100% of the principal amount of the Notes to be redeemed;

plus, in either case, accrued and unpaid interest thereon to, but not including, the Redemption Date.

On or after the Par Call Date, the Company may redeem the Notes in whole or in part, at any time and from time to time, at a Redemption Price equal to 100% of the principal amount of the Notes being redeemed, plus accrued and unpaid interest thereon to, but not including, the Redemption Date.

A-7

6. Mandatory Redemption.

The Company will not be required to make mandatory redemption or sinking fund payments with respect to the Notes.

7. Notice of Redemption.

The Company shall deliver notice of a redemption not less than 10 days nor more than 60 days before the Redemption Date to Holders of Notes to be redeemed. Once notice of redemption is sent, subject to the satisfaction of any conditions precedent provided in the notice of redemption, the Notes called for redemption will become due and payable on the Redemption Date at the applicable Redemption Price.

8. Repurchase at the Option of Holder.

9. Denominations; Transfer; Exchange.

The Notes initially are issued in permanent global form. Under certain circumstances described in the Indenture, Notes may also be issued in the form of certificated Notes in fully registered form, without coupons, in minimum denominations of $2,000 and integral multiples of $1,000 in excess thereof. The Registrar may require a Holder, among other things, to furnish appropriate endorsements and transfer documents and to pay any transfer taxes or similar governmental changes required by law or permitted by the Indenture. The Registrar need not register the transfer or exchange of any Notes selected for redemption in whole or in part (except the unredeemed portion of any Note to be redeemed in part) or any Notes during a period beginning 15 Business Days prior to the delivery of the relevant notice of redemption or repurchase and ending on the close of business on the day of delivery such notice.

A-8

10. Persons Deemed Owners.

The registered Holder of a Note may be treated as its owner for all purposes.

11. Amendment; Waiver.

Subject to certain exceptions and limitations, the Indenture or the Securities may be amended or supplemented with the consent of the Holders of at least a majority in principal amount of the then outstanding Securities of all series affected by such amendment or supplement (acting as one class), and any existing or past Default or Event of Default under, or compliance with any provision of, the Indenture may be waived (other than any continuing Default or Event of Default in the payment of the principal of, premium (if any) on or interest on the Securities) by the Holders of at least a majority in principal amount of the then outstanding Securities of any series or of all series (acting as one class) in accordance with the terms of the Indenture. Subject to certain exceptions set forth in the Indenture, without the consent of any Holder, the Company and the Trustee may amend or supplement the Indenture or the Securities in certain respects set forth in the Indenture.

Without the consent of each Holder affected, the Company may not (i) reduce the amount of Securities whose Holders must consent to an amendment, supplement or waiver; (ii) reduce the rate of or change the time for payment of interest, including default interest, on any Security; (iii) reduce the principal of or premium on, or change the Stated Maturity of, any Security; (iv) reduce the premium, if any, payable upon the redemption of any Security or change the time at which any Security may or shall be redeemed; (v) change any obligation of the Company to pay Additional Amounts with respect to any Security; (vi) change the coin or currency in which any Security or any premium or interest with respect thereto is payable; (vii) impair the right to institute suit for the enforcement of any payment of principal of or premium (if any) or interest on any Security, except as provided in the Indenture; (viii) make any change in the percentage of principal amount of Securities necessary to waive compliance with certain provisions of the Indenture or make any change in the provision for modification; or (ix) waive a continuing Default or Event of Default in the payment of principal of or premium (if any) or interest on the Securities.

A supplemental indenture that changes or eliminates any covenant or other provision of the Indenture which has expressly been included solely for the benefit of one or more particular series of Securities under the Indenture, or which modifies the rights of the Holders of Securities of such series with respect to such covenant or other provision, shall be deemed not to affect the rights under the Indenture of the Holders of Securities of any other series.

A-9

12. Defaults and Remedies.

Under the Indenture, Events of Default include (i) default in the payment of interest that continues for a period of 30 days; (ii) default in any payment of principal of or premium, if any, on the Notes when due and payable; (iii) failure by the Company to comply with any of its other covenants or agreements in the Indenture or the Notes, which shall not have been remedied within the specified time period after written notice; and (iv) certain events of bankruptcy or insolvency with respect to the Company. If an Event of Default occurs and is continuing, either the Trustee or the Holders of at least 25% in aggregate principal amount of the Notes at the time outstanding (or, in the case of an Event of Default described in clause (iii) above, if outstanding Securities of other series are affected by such Default, then at least 25% in principal amount of the then outstanding Securities so affected), may declare the principal amount of all the Securities (or the Notes) to be due and payable immediately, together with accrued and unpaid interest thereon. Certain events of bankruptcy or insolvency are Events of Default that will result in the principal amount of the Notes, together with accrued and unpaid interest thereon, becoming due and payable immediately upon the occurrence of such Events of Default.

As set forth in, and subject to the provisions of, the Indenture, no Holder of any Securities shall have any right to institute any proceeding, judicial or otherwise, with respect to the Indenture, or for the appointment of a receiver or trustee, or for any other remedy thereunder, unless certain conditions set forth in the Indenture have been satisfied. The Trustee may refuse to enforce the Indenture or the Securities unless it receives indemnity satisfactory to it. Subject to certain limitations (including that, in some cases, a majority in principal amount of all outstanding Securities (or the Notes) is required), Holders of a majority in aggregate principal amount of the outstanding Securities (or the Notes) have the right to direct the time, method and place of conducting certain proceedings, or exercising any trust or power conferred on the Trustee.

13. Trustee Dealings with the Company.

Subject to certain limitations imposed by the TIA, the Trustee under the Indenture, in its individual or any other capacity, may become the owner or pledgee of Notes and may otherwise deal with the Company with the same rights it would have if it were not Trustee.

14. Discharge Prior to Maturity.

The Indenture with respect to the Notes shall be discharged and canceled upon the payment of all of the Notes and shall be discharged except for certain obligations upon the irrevocable deposit with the Trustee of any combination of funds and U.S. Government Obligations sufficient for such payment as provided in the Indenture.

15. No Recourse Against Others.

A director, officer, member, manager, employee, stockholder, partner or other owner of the Company or the Trustee, as such, shall not have any liability for any obligations of the Company under the Notes, or for any obligations of the Company or the Trustee under the Indenture or for any claim based on, in respect of or by reason of such obligations or their creation. Each Holder by accepting a Note waives and releases all such liability. The waiver and release shall be part of the consideration for the issuance of Notes.

A-10

16. CUSIP Numbers.

Pursuant to a recommendation promulgated by the Committee on Uniform Security Identification Procedures, the Company has caused CUSIP numbers to be printed on the Notes and the Trustee may use CUSIP numbers in notices of redemption as a convenience to Holders. No representation is made as to the accuracy of such numbers either as printed on the Notes or as contained in any notice of redemption and reliance may be placed only on the other identification numbers placed thereon.

17. Abbreviations.

Customary abbreviations may be used in the name of a Holder or an assignee, such as: TEN COM (= tenants in common), TEN ENT (= tenants by the entireties), JT TEN (= joint tenants with right of survivorship and not as tenants in common), CUST (= Custodian), and U/G/M/A (= Uniform Gifts to Minors Act).

A-11

ASSIGNMENT FORM

To assign this Note, fill in the form below:

I or we assign and transfer this Note to

(Print or type assignee’s name, address and zip code)

(Insert assignee’s soc. sec. or tax I.D. No.)

agent to transfer this Note on the books of the Company. The agent may substitute another to act for him.

A-12

EXHIBIT B

FORM

OF

6.375% SENIOR NOTE DUE 2055

B-1

[FORM OF FACE OF NOTE]

Global Notes Legend

[THIS NOTE IS A GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF THE DEPOSITORY TRUST COMPANY (570 WASHINGTON BOULEVARD, JERSEY CITY, NEW JERSEY) OR OTHER DULY APPOINTED DEPOSITORY (THE “DEPOSITARY”) OR THEIR RESPECTIVE NOMINEES. UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE OR IN PART FOR NOTES IN CERTIFICATED FORM, THIS NOTE MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITARY TO A NOMINEE OF THE DEPOSITARY OR BY A NOMINEE OF THE DEPOSITARY TO THE DEPOSITARY OR ANOTHER NOMINEE OF THE DEPOSITARY OR BY THE DEPOSITARY OR ANY SUCH NOMINEE TO A SUCCESSOR DEPOSITARY OR A NOMINEE OF SUCH SUCCESSOR DEPOSITARY.

UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION, TO THE ISSUER HEREOF OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY (AND ANY PAYMENT IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY), ANY TRANSFER, PLEDGE, OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.]

WESTLAKE CORPORATION

6.375% SENIOR NOTE DUE 2055

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WESTLAKE CORPORATION, a corporation duly organized and existing under the laws of the State of Delaware (herein called the “Company,” which term includes any successor under the Indenture referred to below), for value received, hereby promises to pay to __________________, or its registered assigns, the principal sum of _____________________ ($________________) on the Stated Maturity shown above (or upon any earlier date of redemption or acceleration of maturity) (each such date being hereinafter referred to as the “Maturity Date”) and to pay interest thereon, from and including the immediately preceding Interest Payment Date to which interest has been paid or duly provided for (or from, and including, the Original Issue Date if no interest has been paid or duly provided for), to, but excluding, the Maturity Date, semi-annually in arrears on each Interest Payment Date as specified above, commencing on May 15, 2026 at the rate per annum shown above until the principal hereof is paid or made available for payment and at such rate on any overdue principal and on any overdue installment of interest. Capitalized terms used herein shall have the meanings specified in the Indenture.

Reference is hereby made to the further provisions of this Note set forth on the reverse hereof, which provisions shall for all purposes have the same force and effect as if set forth on the face hereof.

Unless the Certificate of Authentication hereon has been executed by the Trustee, this Note shall not be entitled to any benefit under the Indenture or be valid or obligatory for any purpose.

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IN WITNESS WHEREOF, the Company has caused this instrument to be duly executed.

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CERTIFICATE OF AUTHENTICATION

This is one of the Securities of the series designated therein referred to in the within-mentioned Indenture.

Date of Authentication: ________________, 20__

THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A., as Trustee

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[REVERSE OF NOTE]

Westlake Corporation

6.375% Senior Note due 2055

This Note is one of a duly authorized issue of 6.375% Senior Notes due 2055 (the “Notes”) of Westlake Corporation, a Delaware corporation (the “Company”). Capitalized terms used herein shall have the meanings specified in the Indenture (as defined below).

1. Interest.

The Company promises to pay interest on the principal amount of this Note at the rate per annum shown above. The Company shall pay such interest semi-annually in arrears on May 15 and November 15 of each year, commencing May 15, 2026. Interest will be paid on each such Interest Payment Date to the Persons who are registered Holders of the Notes at the close of business on the May 1 or November 1 (whether or not a Business Day) next preceding the Interest Payment Date (each such date, a “Regular Record Date”), even if such Interest Payment Date is a Redemption Date, Change of Control Payment Date or other Maturity Date, except as provided in Section 2.14 of the Indenture with respect to defaulted interest. Interest on the Notes will accrue from the most recent date to which interest has been paid or duly provided for or, if no interest has been paid or duly provided for, from November 6, 2025. Interest will be computed on the basis of a 360-day year of twelve 30-day months.

2. Method of Payment.

Upon the terms and subject to the conditions of the Indenture, the Company will make all payments of the Redemption Price and Change of Control Payment and principal due at Maturity in respect of the Notes to Holders who surrender such Notes to a Paying Agent to collect such payments; provided that if any Redemption Date, Change of Control Payment Date or other Maturity Date is an Interest Payment Date, accrued and unpaid interest shall be paid to the Holder as of the immediately preceding Regular Record Date. The Company will pay all amounts due in respect of the Notes in money of the United States of America that at the time of payment is legal tender for payment of public and private debts. The Company will make such payments (i) by wire transfer of immediately available funds to any account maintained in the United States with respect to Notes evidenced by Global Securities and any other Notes with any aggregate principal amount in excess of $1,000,000 the Holder of which has provided wire transfer instructions to the Paying Agent at least five Business Days prior to the applicable payment date or (ii) by check payable in such money mailed to a Holder’s registered address with respect to any certificated Notes.

3. Paying Agent and Registrar.

Initially, The Bank of New York Mellon Trust Company, N.A., the Trustee under the Indenture, will act as Paying Agent and Registrar at its office at 601 Travis Street, 16th Floor, Houston, Texas 77002. The Company may appoint and change any Paying Agent or Registrar without notice to any Holder. The Company or any of its Subsidiaries may act as Paying Agent or Registrar.

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4. Indenture.

The Company issued the Notes under an Indenture dated as of January 1, 2006 (the “Base Indenture”), as supplemented by the Fifteenth Supplemental Indenture dated as of November 6, 2025 (the “Fifteenth Supplemental Indenture,” and together with the Base Indenture, the “Indenture”) between the Company and the Trustee. The terms of the Notes include those stated in the Indenture and those made part of the Indenture by reference to the Trust Indenture Act of 1939, as amended (the “TIA”). The Notes are subject to all such terms, and Holders are referred to the Indenture and the TIA for a statement of such terms. To the extent any provision of this Note conflicts with the express provisions of the Indenture, the provisions of the Indenture shall govern and be controlling. The Notes are general unsecured obligations of the Company and are initially issued in an aggregate principal amount of $600,000,000. The Company may, subject to the provisions of the Indenture, issue additional Notes of the same series as the Notes from time to time without the consent of the Holders. The Notes initially issued and any additional Notes subsequently issued under the Indenture will be treated as a single series for all purposes of the Indenture, including, without limitation, with respect to waivers, amendments, supplements, redemptions and offers to purchase, provided that if any such additional Notes are not fungible with the Notes initially issued for United States federal income tax purposes, such additional Notes will have one or more separate CUSIP numbers from the Notes initially issued. The Indenture provides for the issuance of other series of debt securities (including the Notes, the “Securities”) thereunder.

5. Optional Redemption.

Prior to May 15, 2055 (six months prior to the Stated Maturity of the Notes) (the “Par Call Date”), the Company may redeem the Notes at its option, in whole or in part, at any time and from time to time, at a Redemption Price equal to the greater of:

(i) (a) the sum of the present values of the Remaining Scheduled Payments on the Notes to be redeemed discounted to the Redemption Date (assuming the Notes to be redeemed matured on the Par Call Date) on a semi-annual basis (assuming a 360-day year consisting of twelve 30-day months) at the Treasury Rate plus 30 basis points, less (b) interest accrued to the Redemption Date; and

(ii) 100% of the principal amount of the Notes to be redeemed;

plus, in either case, accrued and unpaid interest thereon to, but not including, the Redemption Date.

On or after the Par Call Date, the Company may redeem the Notes in whole or in part, at any time and from time to time, at a Redemption Price equal to 100% of the principal amount of the Notes being redeemed, plus accrued and unpaid interest thereon to, but not including, the Redemption Date.

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6. Mandatory Redemption.

The Company will not be required to make mandatory redemption or sinking fund payments with respect to the Notes.

7. Notice of Redemption.

The Company shall deliver notice of a redemption not less than 10 days nor more than 60 days before the Redemption Date to Holders of Notes to be redeemed. Once notice of redemption is sent, subject to the satisfaction of any conditions precedent provided in the notice of redemption, the Notes called for redemption will become due and payable on the Redemption Date at the applicable Redemption Price.

8. Repurchase at the Option of Holder.

9. Denominations; Transfer; Exchange.

The Notes initially are issued in permanent global form. Under certain circumstances described in the Indenture, Notes may also be issued in the form of certificated Notes in fully registered form, without coupons, in minimum denominations of $2,000 and integral multiples of $1,000 in excess thereof. The Registrar may require a Holder, among other things, to furnish appropriate endorsements and transfer documents and to pay any transfer taxes or similar governmental changes required by law or permitted by the Indenture. The Registrar need not register the transfer or exchange of any Notes selected for redemption in whole or in part (except the unredeemed portion of any Note to be redeemed in part) or any Notes during a period beginning 15 Business Days prior to the delivery of the relevant notice of redemption or repurchase and ending on the close of business on the day of delivery such notice.

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10. Persons Deemed Owners.

The registered Holder of a Note may be treated as its owner for all purposes.

11. Amendment; Waiver.

Subject to certain exceptions and limitations, the Indenture or the Securities may be amended or supplemented with the consent of the Holders of at least a majority in principal amount of the then outstanding Securities of all series affected by such amendment or supplement (acting as one class), and any existing or past Default or Event of Default under, or compliance with any provision of, the Indenture may be waived (other than any continuing Default or Event of Default in the payment of the principal of, premium (if any) on or interest on the Securities) by the Holders of at least a majority in principal amount of the then outstanding Securities of any series or of all series (acting as one class) in accordance with the terms of the Indenture. Subject to certain exceptions set forth in the Indenture, without the consent of any Holder, the Company and the Trustee may amend or supplement the Indenture or the Securities in certain respects set forth in the Indenture.

Without the consent of each Holder affected, the Company may not (i) reduce the amount of Securities whose Holders must consent to an amendment, supplement or waiver; (ii) reduce the rate of or change the time for payment of interest, including default interest, on any Security; (iii) reduce the principal of or premium on, or change the Stated Maturity of, any Security; (iv) reduce the premium, if any, payable upon the redemption of any Security or change the time at which any Security may or shall be redeemed; (v) change any obligation of the Company to pay Additional Amounts with respect to any Security; (vi) change the coin or currency in which any Security or any premium or interest with respect thereto is payable; (vii) impair the right to institute suit for the enforcement of any payment of principal of or premium (if any) or interest on any Security, except as provided in the Indenture; (viii) make any change in the percentage of principal amount of Securities necessary to waive compliance with certain provisions of the Indenture or make any change in the provision for modification; or (ix) waive a continuing Default or Event of Default in the payment of principal of or premium (if any) or interest on the Securities.

A supplemental indenture that changes or eliminates any covenant or other provision of the Indenture which has expressly been included solely for the benefit of one or more particular series of Securities under the Indenture, or which modifies the rights of the Holders of Securities of such series with respect to such covenant or other provision, shall be deemed not to affect the rights under the Indenture of the Holders of Securities of any other series.

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12. Defaults and Remedies.

Under the Indenture, Events of Default include (i) default in the payment of interest that continues for a period of 30 days; (ii) default in any payment of principal of or premium, if any, on the Notes when due and payable; (iii) failure by the Company to comply with any of its other covenants or agreements in the Indenture or the Notes, which shall not have been remedied within the specified time period after written notice; and (iv) certain events of bankruptcy or insolvency with respect to the Company. If an Event of Default occurs and is continuing, either the Trustee or the Holders of at least 25% in aggregate principal amount of the Notes at the time outstanding (or, in the case of an Event of Default described in clause (iii) above, if outstanding Securities of other series are affected by such Default, then at least 25% in principal amount of the then outstanding Securities so affected), may declare the principal amount of all the Securities (or the Notes) to be due and payable immediately, together with accrued and unpaid interest thereon. Certain events of bankruptcy or insolvency are Events of Default that will result in the principal amount of the Notes, together with accrued and unpaid interest thereon, becoming due and payable immediately upon the occurrence of such Events of Default.

As set forth in, and subject to the provisions of, the Indenture, no Holder of any Securities shall have any right to institute any proceeding, judicial or otherwise, with respect to the Indenture, or for the appointment of a receiver or trustee, or for any other remedy thereunder, unless certain conditions set forth in the Indenture have been satisfied. The Trustee may refuse to enforce the Indenture or the Securities unless it receives indemnity satisfactory to it. Subject to certain limitations (including that, in some cases, a majority in principal amount of all outstanding Securities (or the Notes) is required), Holders of a majority in aggregate principal amount of the outstanding Securities (or the Notes) have the right to direct the time, method and place of conducting certain proceedings, or exercising any trust or power conferred on the Trustee.

13. Trustee Dealings with the Company.

Subject to certain limitations imposed by the TIA, the Trustee under the Indenture, in its individual or any other capacity, may become the owner or pledgee of Notes and may otherwise deal with the Company with the same rights it would have if it were not Trustee.

14. Discharge Prior to Maturity.

The Indenture with respect to the Notes shall be discharged and canceled upon the payment of all of the Notes and shall be discharged except for certain obligations upon the irrevocable deposit with the Trustee of any combination of funds and U.S. Government Obligations sufficient for such payment as provided in the Indenture.

15. No Recourse Against Others.

A director, officer, member, manager, employee, stockholder, partner or other owner of the Company or the Trustee, as such, shall not have any liability for any obligations of the Company under the Notes, or for any obligations of the Company or the Trustee under the Indenture or for any claim based on, in respect of or by reason of such obligations or their creation. Each Holder by accepting a Note waives and releases all such liability. The waiver and release shall be part of the consideration for the issuance of Notes.

16. CUSIP Numbers.

Pursuant to a recommendation promulgated by the Committee on Uniform Security Identification Procedures, the Company has caused CUSIP numbers to be printed on the Notes and the Trustee may use CUSIP numbers in notices of redemption as a convenience to Holders. No representation is made as to the accuracy of such numbers either as printed on the Notes or as contained in any notice of redemption and reliance may be placed only on the other identification numbers placed thereon.

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17. Abbreviations.

Customary abbreviations may be used in the name of a Holder or an assignee, such as: TEN COM (= tenants in common), TEN ENT (= tenants by the entireties), JT TEN (= joint tenants with right of survivorship and not as tenants in common), CUST (= Custodian), and U/G/M/A (= Uniform Gifts to Minors Act).

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ASSIGNMENT FORM

To assign this Note, fill in the form below:

I or we assign and transfer this Note to

(Print or type assignee’s name, address and zip code)

(Insert assignee’s soc. sec. or tax I.D. No.)

agent to transfer this Note on the books of the Company. The agent may substitute another to act for him.

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Exhibit 5.1

				AUSTIN		NEW YORK
		910 LOUISIANA		BRUSSELS		PALO ALTO
		HOUSTON, TEXAS		DALLAS		RIYADH
		77002-4995		DUBAI		SAN FRANCISCO
				HOUSTON		SINGAPORE
		TEL +1 713.229.1234		LONDON		WASHINGTON
		FAX +1 713.229.1522
		BakerBotts.com

November 5, 2025

Westlake Corporation

2801 Post Oak Boulevard, Suite 600

Houston, Texas 77056

Ladies and Gentlemen:

Westlake Corporation, a Delaware corporation (the “Company”), has requested that we render the opinion expressed below in connection with the Company’s proposed offering of $600,000,000 aggregate principal amount of the Company’s 5.550% Senior Notes due 2035 (the “2035 Notes”) and $600,000,000 aggregate principal amount of the Company’s 6.375% Senior Notes due 2055 (together with the 2035 Notes, the “Notes”) pursuant to the Registration Statement on Form S-3ASR (Registration No. 333-291208) (the “Registration Statement”) filed by the Company with the Securities and Exchange Commission (the “Commission”) on October 31, 2025 under the Securities Act of 1933, as amended (the “1933 Act”), which relates to the offering and sale of various securities from time to time pursuant to Rule 415 under the 1933 Act.

In our capacity as your counsel in the connection referred to above, we have examined originals, or copies certified or otherwise identified, of (i) the Restated Certificate of Incorporation of the Company and the Second Amended and Restated Bylaws of the Company; (ii) the Indenture, dated as of January 1, 2006 (the “Base Indenture”), among the Company, the potential subsidiary guarantors listed therein and The Bank of New York Mellon Trust Company, N.A. (as successor to JPMorgan Chase Bank, National Association), as trustee (the “Trustee”), and the form of Fifteenth Supplemental Indenture relating to the Notes (the “Supplemental Indenture” and, together with the Base Indenture, the “Indenture”); (iii) the prospectus dated October 31, 2025 forming a part of the Registration Statement and the prospectus supplement dated November 4, 2025 that the Company prepared and filed with the Commission on November 5, 2025, pursuant to Rule 424(b)(5) under the 1933 Act (together, the “Prospectus”); (iv) the Underwriting Agreement dated November 4, 2025 (the “Underwriting Agreement”), by and among the Company and BofA Securities, Inc., Deutsche Bank Securities Inc., J.P. Morgan Securities LLC and Wells Fargo Securities, LLC, as representatives of the several underwriters named in Schedule A thereto (collectively, the “Underwriters”), relating to the offering and sale of the Notes; and (v) corporate records of the Company, including certain resolutions of the Board of Directors of the Company and committees thereof, as furnished to us by the Company, and certificates of public officials and of representatives of the Company, statutes and other instruments and documents, as a basis for the opinion hereinafter expressed. In giving such opinion, we have relied, without independent investigation or verification, upon certificates, statements or other representations of officers and other representatives of the Company and of governmental and public officials with respect to the accuracy of the material factual matters contained in or covered by such certificates, statements or representations. In giving the opinion expressed below, we have assumed that the signatures on all documents examined by us are genuine, that all documents submitted to us as originals are accurate and complete, that all documents submitted to us as copies are true, correct and complete copies of the originals thereof and that all information submitted to us was and remains accurate and complete.

We have also assumed the Base Indenture has been duly authorized, executed and delivered by the Trustee and represents a valid and legally binding obligation of the Trustee, and the Supplemental Indenture has been or will be duly authorized, executed and delivered by the Trustee and will represent a valid and legally binding obligation of the Trustee. In connection with this opinion letter, we have assumed that the Notes will be issued and sold in compliance with applicable federal and state securities laws and in the manner stated in the Registration Statement and the Prospectus.

On the basis of the foregoing, and subject to the assumptions, limitations and qualifications set forth herein, we are of the opinion that the Notes, when they have been duly executed, authenticated, issued and delivered in accordance with the provisions of the Indenture and duly purchased and paid for in accordance with the terms of the Underwriting Agreement, will constitute valid and legally binding obligations of the Company, enforceable against the Company in accordance with their terms, except as such enforceability may be limited by bankruptcy, fraudulent conveyance or transfer, insolvency, reorganization, moratorium and other laws relating to or affecting creditors’ rights generally, by general equitable principles and public policy (regardless of whether such enforceability is considered in a proceeding in equity or at law) and by any implied covenants of good faith and fair dealing.

The opinion set forth above is limited in all respects to matters of the contract law of the State of New York and the General Corporation Law of the State of Delaware, each as in effect as of the date hereof.

We hereby consent to the filing of this opinion letter with the Commission as Exhibit 5.1 to the Company’s Current Report on Form 8-K reporting the offering of the Notes. We also consent to the reference to our Firm under the heading “Legal Matters” in the Prospectus. In giving such consent, we do not hereby admit that we are in the category of persons whose consent is required under Section 7 of the 1933 Act or the rules and regulations of the Commission thereunder.

Exhibit 99.1

Westlake Announces Pricing of $1.2 Billion Offering of Senior Notes

HOUSTON, November 4, 2025 — Westlake Corporation (NYSE: WLK) (“Westlake”) announced today that it has priced its previously announced underwritten public offering of $600,000,000 aggregate principal amount of senior unsecured notes due 2035 (the “2035 Notes”) and $600,000,000 aggregate principal amount of senior unsecured notes due 2055 (the “2055 Notes” and, together with the 2035 Notes, the “Notes”) under its existing shelf registration statement. The 2035 Notes will bear interest at a rate of 5.550% per annum and will mature on November 15, 2035. The 2055 Notes will bear interest at a rate of 6.375% per annum and will mature on November 15, 2055. The sale of the Notes is scheduled to close on November 6, 2025, subject to the satisfaction of customary closing conditions.

Westlake intends to use the net proceeds from the proposed public offering of the Notes to fund the repurchase of its outstanding 3.600% Senior Notes due 2026 (the “2026 Senior Notes”) pursuant to a concurrent cash tender offer (the “Tender Offer”) for any and all of the 2026 Senior Notes. Westlake anticipates using any remaining net proceeds to fund the purchase price of its pending acquisition of the global compounding solutions businesses of the ACI/Perplastic Group (the “ACI Acquisition”) and for general corporate purposes, including working capital management. The offering of the Notes is not contingent upon the successful completion of the Tender Offer or the consummation of the ACI Acquisition.

The Notes are being offered and will be sold only pursuant to an effective shelf registration statement that was previously filed with the Securities and Exchange Commission (“SEC”). This press release shall not constitute an offer to sell or the solicitation of an offer to buy any securities (including the Notes), nor shall there be any sale of these securities in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of such state or jurisdiction. The offering of the Notes is being made only by means of a prospectus and related prospectus supplement meeting the requirements of Section 10 of the Securities Act of 1933, as amended.

This press release shall not constitute an offer to purchase or a solicitation of an offer to sell any of the 2026 Senior Notes. The Tender Offer is being made only by and pursuant to, and on the terms and conditions set forth in, the Offer to Purchase dated November 4, 2025.

BofA Securities, Inc., Deutsche Bank Securities Inc., J.P. Morgan Securities LLC and Wells Fargo Securities, LLC are acting as joint book-running managers for the offering of the Notes. A copy of the preliminary prospectus supplement and accompanying base prospectus relating to the offering of the Notes may be obtained for free by visiting EDGAR on the SEC website at www.sec.gov or by making a request to: BofA Securities, Inc. at 1-800-294-1322; Deutsche Bank Securities Inc. at 1-800-503-4611; J.P. Morgan Securities LLC collect at 1-212-834-4533; or Wells Fargo Securities, LLC at 1-800-645-3751.

About Westlake

Westlake is a global manufacturer and supplier of materials and innovative products that enhance life every day. Headquartered in Houston, with operations in Asia, Europe and North America, Westlake provides the building blocks for vital solutions — from housing and construction, to packaging and healthcare, to automotive and consumer goods.

Contacts

Media Inquiries: Ben Ederington, 713-960-9111;

Investor Inquiries: Steve Bender, 713-960-9111

Forward-Looking Statements

The statements in this press release that are not historical facts, such as statements regarding the proposed public offering of the Notes and the use of proceeds therefrom and other matters relating to the proposed public offering, are forward-looking statements that are based on current expectations. Although Westlake believes that its expectations are based on reasonable assumptions, it can give no assurance that these expectations will prove correct. Important factors that could cause actual results to differ materially from those in the forward-looking statements include results of operations, market conditions, capital needs and uses and other risks and uncertainties that are beyond Westlake’s control, including those described in the preliminary prospectus supplement and accompanying base prospectus relating to the offering of the Notes, Westlake’s Annual Report on Form 10-K for the fiscal year ended December 31, 2024, Westlake’s Quarterly Reports on Form 10-Q for the quarterly periods ended March 31, 2025, June 30, 2025 and September 30, 2025 and its other filings with the SEC. Forward-looking statements, like all statements in this press release, speak only as of the date of this press release (unless another date is indicated). Westlake does not undertake any obligation to publicly update any forward-looking statements, whether as a result of new information, future events, or otherwise.