Minerals Technologies Inc

Item 1.01. Entry into a Material Definitive Agreement Senior Notes due 2032 On October 13, 2026, Minerals Technologies Inc. (the “Company”) completed its previously announced offering of $400,000,000 aggregate principal amount of its 7.500% Senior Notes due 2032 (the “Notes”). The Company intends to use the net proceeds of its offering of the Notes, together with cash on hand, (i) to redeem all of the outstanding 5.000% senior notes due 2028 and (ii) to pay transaction fees and expenses related to this offering and the Amendment (as defined below). The terms of the Notes are governed by an indenture dated as of October 13, 2026 (the “Indenture”), among the Company, the subsidiary guarantors party thereto and U.S. Bank Trust Company, National Association, as trustee (the “Trustee”). The Notes bear interest at a rate of 7.500% per annum payable semi-annually in arrears on January 15 and July 15 of each year, beginning on January 15, 2027. The Notes are guaranteed by the Company’s wholly owned domestic restricted subsidiaries that are obligors or guarantors under its senior secured credit facilities or certain other indebtedness. At any time and from time to time prior to January 15, 2029, the Company may redeem some or all of the Notes for cash at a redemption price equal to 100% of their principal amount, plus the “make-whole” premium described in the Indenture and accrued and unpaid interest, if any, to, but excluding, the applicable redemption date. Beginning on January 15, 2029, the Company may redeem some or all of the Notes at any time and from time to time at the applicable redemption prices listed in the Indenture, plus accrued and unpaid interest, if any, to, but excluding, the applicable redemption date. In addition, at any time and from time to time prior to January 15, 2029, the Company may redeem up to 40% of the aggregate principal amount of the Notes with funds from one or more equity offerings at a redemption price equal to 107.500% of the principal amount thereof, plus accrued and unpaid interest, if any, to, but excluding, the applicable redemption date. If the Company experiences a Change of Control (as defined in the Indenture), the Company is required to offer to repurchase the Notes at 101% of the principal amount of such Notes, plus accrued and unpaid interest, if any, to, but excluding, the date of repurchase. The Indenture contains covenants that, among other things, limit the Company’s ability and the ability of its restricted subsidiaries to incur or guarantee additional indebtedness, pay dividends or make other restricted payments, prepay, redeem or repurchase certain subordinated debt, issue certain preferred stock or similar equity securities, make loans and investments, sell or otherwise dispose of assets, incur liens, enter into transactions with affiliates, enter into agreements restricting its subsidiaries’ ability to pay dividends, and consolidate, merge or sell all or substantially all assets. The Indenture provides for customary events of default which include (subject in certain cases to customary grace and cure periods), among others, nonpayment of principal or interest, breach of other agreements in respect of the Notes, failure to pay certain other indebtedness, failure to pay certain final judgments, failure of certain guarantees to be enforceable and certain events of bankruptcy or insolvency. The foregoing summary and description of the Indenture and the Notes does not purport to be complete and is subject to, and qualified in its entirety by, the full text of the Indenture, which is filed as Exhibit 4.1 hereto and incorporated by reference herein. Amended Credit Agreement On October 13, 2026, the Company entered into a Refinancing Facility Agreement and Incremental Facility Amendment (the “Amendment”) to amend the credit agreement dated as of May 9, 2014 (as amended by the Refinancing Facility Agreement, dated as of June 23, 2015, the Second Amendment, dated as of February 14, 2017, the Third Amendment and Incremental Facility Amendment, dated as of April 18, 2018, the Refinancing Facility Agreement, dated as of August 11, 2022, and the Refinancing Facility Agreement and Incremental Facility Amendment, dated as of November 26, 2024, and as further amended, supplemented, modified, restated, amended and restated or otherwise modified from time to time as of the date hereof, the “Existing Credit Agreement”), among the Company, the borrowing subsidiaries party thereto, the lenders party thereto, JPMorgan Chase Bank, N.A., as administrative agent and collateral agent (in such capacities, the “Administrative Agent”), and the other agents party thereto (the Existing Credit Agreement, as amended by the Amendment, the “Amended Credit Agreement”). The Existing Credit Agreement provided for, among other things, a $564,937,500 senior secured term loan facility (the “Existing Term Loan Facility”) and a $400,000,000 senior secured revolving credit facility (the “Existing Revolving Facility”). The Amendment provides for, among other things, a new senior secured revolving credit facility with aggregate commitments of $500,000,000 (the “Refinancing Revolving Facility”), a portion of which may be used for the issuance of letters of credit and swingline loans. The Refinancing Revolving Facility replaces the Existing Revolving Facility. The maturity date for loans and commitments under the Refinancing Revolving Facility is October 13, 2031, and the maturity date for loans under the Existing Term Loan Facility remains November 26, 2031; provided that the maturity date of the Refinancing Revolving Facility will be adjusted to the date that is 91 days prior to the stated maturity date of the Existing Term Loan Facility unless, prior to the date that is 91 days prior to the stated maturity date of the Existing Term Loan Facility, all amounts in excess of $50,000,000 of the Existing Term Loan Facility have been either (a) refinanced with indebtedness permitted under the Amended Credit Agreement maturing later than 90 days after the scheduled maturity date of the Existing Term Loan Facility or (b) discharged or repaid (other than with the proceeds of any indebtedness maturing earlier than 91 days after the scheduled maturity date of the Refinancing Revolving Facility). The Amendment does not change any terms of the Existing Term Loan Facility and, except as set forth above, the terms of the Refinancing Revolving Facility (including interest rates and fees) remain the same as the Existing Revolving Facility. The foregoing description of the Amendment and the Amended Credit Agreement does not purport to be complete and is qualified in its entirety by reference to the Amendment, including the exhibits thereto, which is attached hereto as Exhibit 10.1 to this Current Report on Form 8-K, and is incorporated herein by reference.

Item 2.03. Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant The information set forth in Item 1.01 of this Current Report on Form 8-K is incorporated by reference in this Item 2.03.