MLM: 8-K/A company filing

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K/A ( Amendment No. 1 ) CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 21, 2026 Martin Marietta Materials, Inc. (Exact name of registrant as specified in its charter) North Carolina 001-12744 56-1848578 (State or other jurisdiction of incorporation) (Commission File Number) (I.R.S. Employer Identification No.) 4123 Parklake Avenue Raleigh , North Carolina 27612 (Address of principal executive offices) (Zip Code) Registrant’s telephone number, including area code: 919 - 781-4550 Not Applicable (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 Name of Each Exchange on Which Registered Common Stock, $0.01 par value per share MLM 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, indic