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Item 9A. Controls and Procedures

2026-02-20 compared with 2025-02-20 · 56 added, 43 removed, 142 unchanged (41% of the section changed)

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Our chief executive officer and our chief financial officer evaluated the effectiveness of our disclosure controls and procedures as of December 31, 2025.

Based on that evaluation, our chief executive officer and chief financial officer have concluded that, as of such date, our disclosure controls and procedures were effective to ensure that information Olin is required to disclose in the reports that it files or submits with the SEC under the Securities Exchange Act of 1934 is recorded, processed, summarized and reported within the time periods specified in the Commission’s rules and forms, and to ensure that information we are required to disclose in such reports is accumulated and communicated to our management, including our chief executive officer and chief financial officer, as appropriate to allow timely decisions regarding required disclosure.

Based on that evaluation, our chief executive officer and chief financial officer have concluded that, as of such date, our disclosure controls and procedures were effective to ensure that information Olin is required to disclose in the reports that it files or submits with the Securities and Exchange Commission (SEC) under the Securities Exchange Act of 1934 is recorded, processed, summarized and reported within the time periods specified in the SEC’s rules and forms, and to ensure that information we are required to disclose in such reports is accumulated and communicated to our management, including our Chief Executive Officer and Chief Financial Officer, as appropriate to allow timely decisions regarding required disclosure.

There have been no changes in our internal control over financial reporting that occurred during the quarter ended December 31, 2025, that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

Management’s report on internal control over financial reporting and the related report of Olin’s independent registered public accounting firm, KPMG LLP, are included in Item 8—“Consolidated Financial Statements and Supplementary Data.”

OTHER INFORMATION

During the three months ended December 31, 2025, no director or officer of Olin adopted or terminated a ‘Rule 10b5-1 trading arrangement’ or ‘non-Rule 10b5-1 trading arrangement,’ as each term is defined in Item 408(a) of Regulation S-K.

First Amendment to Credit Agreement

On February 19, 2026, Olin executed an Amendment (the “First Amendment”) to the Credit Agreement dated as of March 14, 2025 (as amended by the First Amendment, the “Amended Credit Agreement”), by and among Olin, the lenders from time to time party thereto, the issuing banks from time to time party thereto and Bank of America, N.A., in its capacity as administrative agent, to, among other things, provide Olin with greater flexibility under the financial maintenance covenants of the Amended Credit Agreement.

The First Amendment also provides for two additional increased pricing levels applicable to drawn and undrawn amounts under the credit facilities under the Amended Credit Agreement if Olin’s leverage ratio exceeds specified ratios.

Olin also repaid $109.7 million of the term loan facility thereunder with the proceeds of a borrowing under the revolving credit facility.

The First Amendment requires that Olin’s obligations under the Amended Credit Agreement, certain cash management arrangements and hedging arrangements, certain letter of credit reimbursement facilities and certain other specified obligations be guaranteed by certain of its material domestic subsidiaries, and that such obligations also be secured by liens on substantially all of Olin’s and the subsidiary guarantors’ personal property, other than certain principal properties, capital stock of subsidiaries and subject to certain other exceptions.

The First Amendment provides that all guarantees under the Amended Credit Agreement and liens on the collateral will be released upon the earlier of (a) September 30, 2027 and (b) Olin’s election, upon at least five business days’ notice, to terminate the covenant relief period (the period from the effectiveness of the First Amendment until such earlier date is referred to herein as the “Covenant Relief Period”).

The First Amendment relaxes the financial maintenance covenants that Olin must comply with by (a) reducing the minimum consolidated interest coverage ratio covenant during the Covenant Relief Period, (b) increasing the maximum consolidated net leverage ratio covenant during the Covenant Relief Period and (c) adjusting the calculation of the EBITDA and debt components that form the basis of determining Olin’s compliance with the foregoing financial maintenance covenants.

The First Amendment (i) limits Olin’s ability to incur debt, (ii) limits its ability to pay dividends or distributions in excess of its regularly scheduled dividends, (iii) limits its ability to engage in certain asset sales and (iv) requires that the net

cash proceeds of certain asset sales be used to prepay funded loans under the term loan facility, in each case subject to exceptions and baskets as specified in the First Amendment and solely during the Covenant Relief Period.

The foregoing description of the First Amendment does not purport to be complete and is qualified in its entirety by reference to the full text of the First Amendment, which is attached hereto as Exhibit 10.31 and which is incorporated by reference herein.

Fourteenth Amendment to Amended and Restated Credit and Funding Agreement

On February 19, 2026, Olin executed a Fourteenth Amendment (the “Fourteenth Amendment”) to the Amended and Restated Credit and Funding Agreement dated as of December 9, 2010, among Olin, the lenders thereunder, and PNC Bank, National Association, as administrative agent, related to The Industrial Development Authority of Washington County Series 2010A bonds, The Industrial Development Authority of Washington County Series 2010B bonds, The Mississippi Business Finance Corporation Series 2010 bonds and The Industrial Development Board of the County of Bradley and the City of Cleveland, Tennessee Series 2010 bonds to provide the lenders thereunder with equal and ratable guarantees and collateral and to amend certain covenants, definitions and pricing terms to be consistent with the covenants, definitions and pricing terms contained in the Amended Credit Agreement described in Item 9B.

The foregoing description of the Fourteenth Amendment does not purport to be complete and is qualified in its entirety by reference to the full text of the Fourteenth Amendment, which is attached hereto as Exhibit 4.22 and which is incorporated by reference herein.

Performance Share Program

Effective February 18, 2026, the Compensation Committee of the Board of Directors of Olin adopted an updated Performance Share Program that replaces the net income performance metric with adjusted EBITDA and includes total shareholder return performance as a modifier in determining payouts under the plan.

These changes will be effective beginning with performance share grants in 2026.

The updated Olin Corporation Performance Share Program is qualified in its entirety by reference to the full text of such document which is filed herewith as Exhibit 10.18 to this report.

DISCLOSURE REGARDING FOREIGN JURISDICTIONS THAT PREVENT INSPECTIONS

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DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE

We incorporate the biographical information relating to our Directors under the heading ITEM 1—“PROPOSAL FOR THE ELECTION OF DIRECTORS” in our Proxy Statement relating to our 2025 Annual Meeting of Shareholders (the “Proxy Statement”) by reference in this Report.

We incorporate the biographical information relating to our Board of Directors (Board) under the heading ITEM 1—“PROPOSAL FOR THE ELECTION OF DIRECTORS” in our Proxy Statement relating to our 2026 Annual Meeting of Shareholders (the “Proxy Statement”) by reference in this Report.

We incorporate the biographical information regarding executive officers under the heading “EXECUTIVE OFFICERS” in our Proxy Statement by reference in this Report.

We incorporate the information regarding compliance with Section 16 of the Securities Exchange Act of 1934, as amended, under the heading entitled “DELINQUENT SECTION 16(a) REPORTS” in our Proxy Statement by reference in this Report.

The information with respect to our audit committee, including the audit committee financial expert, is incorporated by reference in this Report to the information contained in the paragraph entitled “CORPORATE GOVERNANCE MATTERS—What Are our Board Committees?” in our Proxy Statement.

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EXECUTIVE COMPENSATION

The information in the Proxy Statement under the heading “CORPORATE GOVERNANCE MATTERS—Compensation Committee Interlocks and Insider Participation,” and the information under the heading “COMPENSATION DISCUSSION AND ANALYSIS” through the information under the heading “COMPENSATION COMMITTEE REPORT,” are incorporated by reference in this Report.

The information in the Proxy Statement under the heading “CORPORATE GOVERNANCE MATTERS—Compensation Committee Interlocks and Insider Participation,” the information under the heading “COMPENSATION DISCUSSION AND ANALYSIS” through the information under the heading “PAY RATIO DISCLOSURE” are incorporated by reference in this Report.

SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND RELATED STOCKHOLDER MATTERS

We incorporate the information concerning holdings of our common stock by certain beneficial owners contained under the heading “CERTAIN BENEFICIAL OWNERS” in our Proxy Statement, and the information concerning beneficial ownership of our common stock by our directors and officers under the heading “SECURITY OWNERSHIP OF DIRECTORS AND OFFICERS” in our Proxy Statement by reference in this Report.

Equity compensation plans information as of December 31, 2024 follows:

Equity Compensation Plan Information

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We incorporate the information under the headings “CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS” and “CORPORATE GOVERNANCE MATTERS—Which Board Members Are Independent?” in our Proxy Statement by reference in this Report.

PRINCIPAL ACCOUNTING FEES AND SERVICES

PRINCIPAL ACCOUNTANT FEES AND SERVICES

Our independent registered public accounting firm is KPMG LLP , St.

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Consolidated Financial Statements

Consolidated financial statements of the registrant are included in Item 8 above.

Consolidated financial statements of the registrant are included in Item 8—“Financial Statements and Supplementary Data” above.

Financial Statement Schedules

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3.1 Amended and Restated Articles of Incorporation of Olin Corporation as amended effective April 24, 2020—Exhibit 3.1 to Olin’s Form 8-K filed April 28, 2020 *

3.2 Bylaws of Olin Corporation as amended effective June 5, 2023—Exhibit 3.1 to Olin's Form 8-K filed June 5, 2023 *

4.1 Description of Olin Corporation Securities registered under Section 12 of the Exchange Act

4.2 Indenture dated as of August 19, 2009, between Olin Corporation and The Bank of New York Mellon Trust Company, N.A., as Trustee — Exhibit 4.1 of Olin’s Current Report on Form 8-K dated August 19, 2009 *

3.2 Bylaws of Olin Corporation as amended effective August 13, 2025—Exhibit 3.1 to Olin's Form 8-K filed August 13, 2025 *

4.1 Description of Olin Corporation Securities registered under Section 12 of the Exchange Act—Exhibit 4.1 to Olin's Form 10-K filed February 20, 2025 *

4.2 Indenture dated as of August 19, 2009, between Olin Corporation and The Bank of New York Mellon Trust Company, N.A., as Trustee — Exhibit 4.1 of Olin’s Form 8-K dated August 19, 2009 *

4.3 Trust Indenture effective December 1, 2010 between Mississippi Business Finance Corporation and U.S.

Bank National Association—Exhibit 4.1 to Olin’s Form 8-K filed December 10, 2010 *

4.4 Fourth Supplemental Indenture dated as of March 9, 2017 between Olin Corporation and U.S.

Bank National Association—Exhibit 4.3 to Olin’s Form 8-K filed March 9, 2017 *

4.4 Fifth Supplemental Indenture dated January 16, 2018 between Olin Corporation and U.S.

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4.20 Twelfth Amendment to Amended and Restated Credit and Funding Agreement, dated as of October 11, 2022, among Olin Corporation, the Lenders (as defined therein), and PNC Bank, National Association, as administrative agent — Exhibit 4.1 to Olin's Form 8-K filed October 12, 2022 *

4.21 Thirteenth Amendment to Amended and Restated Credit and Funding Agreement, dated as of March 14, 2025, among Olin Corporation, the Lenders (as defined therein) and PNC Bank, National Association, as administrative agent – Exhibit 4.3 to Olin’s Form 8-K filed March 14, 2025*

4.22 Fourteenth Amendment, dated February 19, 2026, to Amended and Restated Credit and Funding Agreement, dated as of February December 9, 2010 among Olin Corporation, the Lenders (as defined therein) and PNC Bank, National Association, as administrative agent

4.23 Forward Purchase Agreement dated as of March 9, 2017, among Olin Corporation, the Lenders as named therein, and PNC Bank, National Association, as administrative agent—Exhibit 4.1 to Olin’s Form 8-K filed March 9, 2017 *

4.24 First Amendment dated August 30, 2021 to Forward Purchase Agreement dated March 9, 2017, among Olin Corporation, Olin Winchester, LLC, the Lenders as named therein, and PNC Bank, National Association , as administrative agent—Exhibit 4.2 to Olin’s Form 10-Q filed October 22, 2021 *

4.25 Senior Notes Indenture dated May 19, 2020 among Olin Corporation, as issuer, and U.S.

Bank National Association, as trustee, governing the Senior Notes—Exhibit 4.1 to Olin’s Form 8-K filed May 20, 2020 *

4.26 First Supplemental Indenture dated September 30, 2020 between Olin Corporation, as issuer, as issuer, and U.S.

Bank National Association, as trustee, governing the 9.500% Senior Notes due 2025—Exhibit 4.4 to Olin’s Form 10-Q filed November 5, 2020 *

4.27 Second Supplemental Indenture dated November 15,2021 between Olin Corporation, as issuer, as issuer, and U.S.

Bank National Association, as trustee, governing the 9.500% Senior Notes due 2025—Exhibit 4.1 to Olin’s Form 8-K filed November 16, 2021 *

4.28 Form of 5.125% Senior Notes due 2027—Exhibit 4.4 (included in Exhibit 4.3) to Olin’s Form 8-K filed March 9, 2017 *

4.29 Form of 5.000% Senior Notes due 2030—Exhibit 4.1 to Olin’s Form 8-K filed January 19, 2018 *

4.30 Form of 5.625% Senior Notes due 2029—Exhibit 4.2 (included in Exhibit 4.1) to Olin’s Form 8-K filed July 16, 2019 *

4.31 Form of 9.500% Senior Notes due 2025—Exhibit 4.2 (included in Exhibit 4.1) to Olin’s Form 8-K filed May 20, 2020 *

4.25 Third Amendment dated March 14, 2025 to Forward Purchase Agreement dated March 9, 2017, among Olin Corporation, Olin Winchester, LLC, the Lenders as named therein, and PNC Bank, National Association, as administrative agent—Exhibit 4.1 to Olin’s Form 10-Q filed May 2, 2025*

4.26 Form of 5.000% Senior Notes due 2030—Exhibit 4.

2 (contained in Exhibit 4.1) to Olin’s Form 8-K filed January 19, 2018 *

4.27 Form of 5.625% Senior Notes due 2029—Exhibit 4.2 ( contained in Exhibit 4.1) to Olin’s Form 8-K filed July 16, 2019 *

4.28 Receivables Purchase Agreement, dated as of November 20, 2024, among Olin Corporation, as servicer, Olin Finance Company, LLC, as seller, PNC Bank, National Association, as administrative agent, PNC Capital Markets LLC, as structuring agent, and the persons from time to time parties thereto as purchasers and group agents—Exhibit 10.1 to Olin’s Form 8-K filed November 20, 2024 *

Indenture, dated as of March 14, 2025, between Olin Corporation and U.S.

Bank Trust Company, National Association, as trustee, governing the Senior Notes—Exhibit 4.1 to Olin’s Form 8-K filed March 14, 2025*

Form of 6.625% Senior Note due 2023—Exhibit 4.2 (contained in Exhibit 4.1) to Olin’s Form 8-K filed March 14, 2025*

10.1 Senior Executive Pension Plan amended and restated effective October 24, 2008—Exhibit 10.1 to Olin’s Form 10-Q filed October 27, 2008 *†

10.2 Olin Corporation Supplemental Retirement Savings Plan—Exhibit 10.1 to Olin’s Form 8-K filed October 1, 2024 *†

10.3 Olin Corporation Change in Control Severance Plan for Section 16(b) Officers effective April 24, 2024 †

10.4 Olin Corporation Severance Plan for Section 16(b) Officers effective April 24, 2024 †

10.5 Amended and Restated 1997 Stock Plan for Non-employee Directors codified to reflect amendments adopted through December 5, 2024

10.6 Description of Restricted Stock Unit Awards granted under one of Olin's Long Term Incentive Plans—Exhibit 10.6 to Olin's Form 10-K filed February 23, 2023 *†

10.3 Olin Corporation Change in Control Severance Plan for Section 16(b) Officers effective April 24, 2024—Exhibit 10.3 to Olin’s Form 10-K filed February 20, 2025 *†

10.4 Olin Corporation Severance Plan for Section 16(b) Officers effective April 24, 2024—Exhibit 10.4 to Olin’s Form 10-K filed February 20, 2025 *†

10.5 Amended and Restated 1997 Stock Plan for Non-employee Directors codified to reflect amendments adopted through December 5, 2024—Exhibit 10.5 to Olin’s Form 10-K filed February 20, 2025 *†

10.6 Supplementary and Deferral Benefit Pension Plan as amended and restated effective October 24, 2008—Exhibit 10.2 to Olin’s Form 10-Q filed October 27, 2008 *†

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Amended and Restated Olin Corporation 2018 Long Term Incentive Plan codified as of January 27, 2019—Exhibit 10.7 to Olin’s Form 8-K filed January 30, 2019 *†

10.14 Amended and Restated Olin Corporation 2021 Long Term Incentive Plan codified as of April 22, 2021—Exhibit 10.1 to Olin’s Form 8-K/A filed April 26, 2021 *†

10.12 Amended and Restated Olin Corporation 2021 Long Term Incentive Plan codified as of January 1, 2025 †

10.13 Olin Corporation Section 16 Short-Term Incentive Plan—Exhibit 10.1 to Olin’s Form 8-K filed December 13, 2023 *†

Performance Share Program amended December 5, 2024 †

10.17 Offer Letter dated July 14, 2020 by and between Scott M.

Sutton and Olin Corporation—Exhibit 10.1 to Olin’s Form 8-K filed July 15, 2020 *†

Equity Award Continuation Policy amended December 5, 2024—Exhibit 10.16 to Olin’s Form 10-K filed February 20, 2025 *†

10.15 Form of Non-Qualified Stock Option Award Certificate—Exhibit 10.19 to Olin's Form 10-K filed February 23, 2023 *†

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10.17 Form of Performance Award Certificate—Exhibit 10.21 to Olin's Form 10-K filed February 23, 2023 *†

Restricted Stock Award to Damian Gumpel dated December 10, 2021 and related Description—Exhibit 10.2 to Olin’s Form 8-K filed December 10, 2021 *†

Summary of Olin Performance Share Program as amended effective F ebrua ry 21, 2024 †

Form of Performance Share Award Notice and Agreement †

Olin Corporation Retirement Savings Plan Amended and Restated effective as of January 1, 2024—Exhibit 10.1 to Olin’s Form 10-Q filed October 25, 2024 *

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10.25 Credit Agreement dated October 11, 2022 among Olin Corporation, the Lenders as named therein and Bank of America, N.A., as administrative agent—Exhibit 10.1 to Olin’s Form 8-K filed October 12, 2022 *

Transition Agreement between Olin Corporation and Scott Sutton, Dated October 30, 2023 - Exhibit 10.1 to Olin’s Form 8-K filed November 2, 2023 *†

Form of Olin Corporation Retention Agreement—Exhibit 10.1 to Olin's Form 8-K filed December 20, 2023 *†

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Separation Agreement, dated January 20, 2025, by and between Olin Corporation and Damian Gumpel—Exhibit 10.1 to Olin’s Form 8-K filed January 21, 2025 *†

I nsider Trading Policy

Credit Agreement, dated as of March 14, 2025, among Olin Corporation, the Lenders and Issuing Banks (as defined therein) and Bank of America, N.A., as administrative agent—Exhibit 10.1 to Olin’s Form 8-K filed March 14, 2025*

First Amendment, dated February 19, 2026, to Credit Agreement, dated as of March 14, 2025, among Olin Corporation, the Lenders and Issuing Banks (as defined therein) and Bank of America, N.A., as administrative agent * *

Non-Employee Director Deferred Compensation Plan, effective November 12, 2025 †

19 Insider Trading Policy—Exhibit 19 to Olin’s Form 10-K filed February 20, 2025*

21 Subsidiaries of Olin Corporation

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97 Olin Corporation Executive Officer Clawback Policy—Exhibit 97 to Olin’s Form 10-K filed February 22, 2024*

101.INS XBRL Instance Document (the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the XBRL document)

101.INS Inline XBRL Instance Document (the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the XBRL document)

101.SCH XBRL Taxonomy Extension Schema Document

101.CAL XBRL Taxonomy Extension Calculation Linkbase Document

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101.PRE XBRL Taxonomy Extension Presentation Linkbase Document

104 Cover Page Interactive Data File (embedded in the Exhibit 101 Interactive Data Files)

101.CAL Inline XBRL Taxonomy Extension Calculation Linkbase Document

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101.LAB Inline XBRL Taxonomy Extension Label Linkbase Document

101.PRE Inline XBRL Taxonomy Extension Presentation Linkbase Document

104 Cover Page Interactive Data File (formatted as Inline XBRL and embedded in the Exhibit 101 Interactive Data Files)

* Previously filed as indicated and incorporated herein by reference.

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1-1070 unless otherwise indicated.

** Certain exhibits and schedules to this agreement have been omitted pursuant to Item 601(a)(5) of Regulation S-K and will be provided to the Securities and Exchange Commission upon request.

† Indicated management contract or compensatory arrangement.

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Shareholders may obtain information from EQ Shareowner Services, our registrar and transfer agent, who also manages our Automatic Dividend Reinvestment Plan by writing to:

EQ Shareowner Services, 1110 Centre Pointe Curve, Suite 101, Mendota Heights, MN 55120 USA, by telephone from the United States at 800-401-1957 or outside the United States at 651-450-4064 or via their website under “Contact Us” at www.shareowneronline.com .The contents of EQ Shareowner Services’ website referenced in this section are not, and should not be considered to be, part of this Report.

FORM 10-K SUMMARY

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BABCOCK Director February 20, 2026

Director February 20, 2025

/s/ EDWARD M.

DALY Director February 20, 2026

/s/ MATTHEW S.

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Compared sentence by sentence after normalising whitespace, quotation marks, case and digits, so re-formatting and restated figures do not read as changed language. Wording changes appear as one removal and one addition. The current filing and the prior one are authoritative.

What changed 10-K

Item 9A. Controls and Procedures