Reg FD Disclosure

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549   FORM 8-K   CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 18, 2025     AMPCO-PITTSBURGH CORPORATION (Exact name of Registrant as Specified in Its Charter)     Pennsylvania 1-898 25-1117717 (State or Other Jurisdiction of Incorporation) (Commission File Number) (IRS Employer Identification No.)           726 Bell Avenue Suite 301   Carnegie , Pennsylvania   15106 (Address of Principal Executive Offices)   (Zip Code)   Registrant’s Telephone Number, Including Area Code: 412 456-4400     (Former Name or Former Address, if Changed Since Last Report)   Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions: ☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Securities registered pursuant to Section 12(b) of the Act: Title of each class   Trading Symbol(s)   Name of each exchange on which registered Common Stock, $1 par value   AP   New York Stock Exchange Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter). Emerging growth company ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐   Item 7.01 Regulation FD Disclosure. On November 18, 2025, Ampco-Pittsburgh Corporation (the “Corporation”) posted an investor presentation to its investor relations website (www.ampcopgh.com/investors). This presentation, or excerpts from this presentation, may be provided to existing and/or prospective investors during future meetings. The investor presentation is furnished herewith as Exhibit 99.1. The information in this Item 7.01 shall not be deemed to be “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934 (the “Exchange Act”) or otherwise subject to the liabilities of that section, nor shall it be incorporated by reference into a filing under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such a filing. The information on the Corporation’s website is not part of this Current Report on Form 8-K. Item 9.01 Financial Statements and Exhibits. (d) Exhibits       Exhibit 99.1 Ampco-Pittsburgh Corporation Investor Presentation (November 2025)   Exhibit 104 Cover Page Interactive Data File (embedded within the Inline XBRL document)   SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.       AMPCO-PITTSBURGH CORPORATION         Date: November 18, 2025 By: /s/ Michael G. McAuley       Michael G. McAuley Senior Vice President, Chief Financial Officer and Treasurer