and Exhibit 99.1 shall not be deemed filed for the purposes of Section 18 of the Securities and Exchange Act of 1934, as amended, or incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing. Item 9.01 | Financial Statements and Exhibits. (d) | Exhibits 99.1 | Press Release dated October 29, 2026 104 | Cover Page Interactive Data File (formatted as inline XBRL) SIGNATURES Pursuant to the re…

Other Events. On October 21, 2026, the Company’s Board of Directors declared a regular quarterly dividend of $0.13 per share on the Company's common stock. The dividend is payable on December 3, 2026, to the stockholders of record on November 5, 2026. A copy of the press release announcing the dividend declaration is attached hereto as Exhibit 99.1 and incorporated by reference herein.

Forward-Looking Statements This current report contains “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements provide current expectations and forecasts of future events such as new products, revenues, and financial performance, and are not limited to describing historical or current facts. They can be identified by the use of words such as “outlook,” “forecast,” “believes,” “expects,” “plans,” “intends,” “anticipat…

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…

Other Events. Pricing of Notes Offering On October 1, 2026, Minerals Technologies Inc. (the “Company”) issued a press release announcing the pricing of the previously announced private offering (the “Offering”) of $400 million aggregate principal amount of its 7.500% senior notes due 2032 (the “Notes”) in a transaction exempt from registration under the Securities Act of 1933, as amended (the “Securities Act”), a copy of which is attached hereto as Exhibit 99.1 and is incorporated herein by r…

Other Events. Announcement of Notes Offering On October 1, 2026, Minerals Technologies Inc. (the “Company”) issued a press release announcing the commencement of a private offering of senior notes (the “Notes”) in a transaction exempt from registration under the Securities Act of 1933, as amended (the “Securities Act”), a copy of which is attached hereto as Exhibit 99.1 and is incorporated herein by reference. The Notes and the related guarantees have not been registered under the Securities…

and Exhibit 99.1 shall not be deemed filed for the purposes of Section 18 of the Securities and Exchange Act of 1934, as amended, or incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing.

Other Events. On July 22, 2026, the Company’s Board of Directors declared a regular quarterly dividend of $0.12 per share on the Company's common stock. The dividend is payable on September 4, 2026, to the stockholders of record on August 14, 2026. A copy of the press release announcing the dividend declaration is attached hereto as Exhibit 99.1 and incorporated by reference herein.

Other Events On May 19, 2026, the Company’s Board of Directors declared a regular quarterly dividend of $0.12 per share on the Company's common stock. The dividend is payable on June 18, 2026 to the stockholders of record on June 2, 2026. A copy of the press release announcing the dividend declaration is attached hereto as Exhibit 99.1 and incorporated by reference herein.

and Exhibit 99.1 shall not be deemed filed for the purposes of Section 18 of the Securities and Exchange Act of 1934, as amended, or incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing.

Senior Vice President, M&A and Strategy — Jonathan J. Hastings: Mr. Hastings is stepping down from his position but will continue in a new role as Corporate Strategy Advisor.

Director — Alison A. Deans and Franklin L. Feder: Directors Alison A. Deans and Franklin L. Feder are retiring from the Board at the annual meeting.

and Exhibit 99.1 shall not be deemed filed for the purposes of Section 18 of the Securities and Exchange Act of 1934, as amended, or incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing.

Other Events. On January 21, 2026, the Company’s Board of Directors declared a regular quarterly dividend of $0.12 per share on the Company's common stock. The dividend is payable on March 6, 2026, to the stockholders of record on February 13, 2026. A copy of the press release announcing the dividend declaration and the share repurchase program is attached hereto as Exhibit 99.1 and incorporated by reference herein.

Results of Operations and Financial Condition. On October 23, 2025, Minerals Technologies Inc. issued a press release regarding its financial performance for the third quarter of 2025. A copy of the press release is attached hereto as Exhibit 99.1 and incorporated by reference herein. The information in this

Other Events. On October 15, 2025, the Company’s Board of Directors declared a regular quarterly dividend of $0.12 per share on the Company's common stock. The dividend is payable on December 04, 2025, to the stockholders of record on October 30, 2025. A copy of the press release announcing the dividend declaration and the share repurchase program is attached hereto as Exhibit 99.1 and incorporated by reference herein.

Results of Operations and Financial Condition. On July 24, 2025, Minerals Technologies Inc. issued a press release regarding its financial performance for the second quarter of 2025. A copy of the press release is attached hereto as Exhibit 99.1 and incorporated by reference herein. The information in this

Other Events. On July 16, 2025, the Company’s Board of Directors declared a regular quarterly dividend of $0.11 per share on the Company's common stock. The dividend is payable on September 5, 2025, to the stockholders of record on August 15, 2025. A copy of the press release announcing the dividend declaration is attached hereto as Exhibit 99.1 and incorporated by reference herein.

Other Events On May 13, 2025, the Company’s Board of Directors declared a regular quarterly dividend of $0.11 per share on the Company's common stock. The dividend is payable on June 12, 2025 to the stockholders of record on May 30, 2025. A copy of the press release announcing the dividend declaration is attached hereto as Exhibit 99.1 and incorporated by reference herein.

Results of Operations and Financial Condition. On April 24, 2025, Minerals Technologies Inc. issued a press release regarding its financial performance for the first quarter of 2025. A copy of the press release is attached hereto as Exhibit 99.1 and incorporated by reference herein. The information in this

Results of Operations and Financial Condition. On April 17, 2025, Minerals Technologies Inc. issued a press release announcing certain preliminary financial results for the first quarter of 2025 and providing an update on its subsidiaries' Chapter 11 cases. A copy of the press release is attached hereto as Exhibit 99.1 and incorporated by reference herein. The information in this

Results of Operations and Financial Condition. On February 6, 2025, Minerals Technologies Inc. issued a press release regarding its financial performance for the fourth quarter of 2024. A copy of the press release is attached hereto as Exhibit 99.1 and incorporated by reference herein. The information in this

Results of Operations and Financial Condition. On February 6, 2025, Minerals Technologies Inc. issued a press release regarding its financial performance for the fourth quarter of 2024. A copy of the press release is attached hereto as Exhibit 99.1 and incorporated by reference herein. The information in this

Other Events. On January 22, 2025, the Company’s Board of Directors declared a regular quarterly dividend of $0.11 per share on the Company's common stock. The dividend is payable on March 7, 2025, to the stockholders of record on February 14, 2025. A copy of the press release announcing the dividend declaration is attached hereto as Exhibit 99.1 and incorporated by reference herein.

Other Events On November 26, 2024, the Company issued a press release announcing the Amendment and the Amended Credit Agreement. The full text of the press release is included as Exhibit 99.1 to this Current Report on Form 8-K.