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NL Industries, Inc._March 9, 2026 NYSE0000072162falseNL Industries, Inc.00000721622026-03-092026-03-09 ​

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) March 9, 2026 ​ NL Industries, Inc. (Exact name of registrant as specified in its charter) ​ ​

​

​

New Jersey 1-640 13-5267260

(State or other jurisdiction of incorporation) (Commission File Number) (IRS Employer Identification No.)

​ ​ ​

​

5430 LBJ Freeway, Suite 1700, Dallas, Texas 75240-2620

(Address of principal executive offices) (Zip Code)

​ Registrant’s telephone number, including area code (972) 233-1700 ​

​

​

​

(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 (see General Instruction A.2): ​ ​

​

☐ 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 ​ NL ​ 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 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2). 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 2.02Results of Operations and Financial Condition. ​ The registrant hereby furnishes the information set forth in its press release entitled “NL Reports Fourth Quarter 2025 Results” issued on March 9, 2026, a copy of which is attached hereto as Exhibit 99.1 and incorporated herein by reference. ​ The press release the registrant furnishes as Exhibit 99.1 to this current report is not deemed “filed” for purposes of section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section.  Registration statements or other documents filed with the U.S. Securities and Exchange Commission shall not incorporate this information by reference, except as otherwise expressly stated in such filing. ​ ​ Item 9.01Financial Statements and Exhibits. ​ ​

​

​

​

(d) Exhibits ​ ​

​ ​ ​ ​

​ Item No. ​ ​ ​ Description

​ ​ ​ ​

​ 99.1 ​ Press release dated March 9, 2026 entitled “NL Reports Fourth Quarter 2025 Results” and issued by the registrant.

​ ​ ​ ​

​ 104 ​ Cover Page Interactive Data File (embedded within the Inline XBRL document)

​ ​ ​ ​

​ ​

SIGNATURE

​ 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. ​ ​

​

​

NL INDUSTRIES, INC.

​ (Registrant)

​ ​

​ ​

​ ​

Date: March 9, 2026 By: /s/Amy A. Samford

​ Amy A. Samford Executive Vice President and Chief Financial Officer

​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

NL Industries, Inc._November 6, 2025 NYSE0000072162falseNL Industries, Inc.00000721622025-11-062025-11-06 ​

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 6, 2025 ​ NL Industries, Inc. (Exact name of registrant as specified in its charter) ​ ​

​

​

New Jersey 1-640 13-5267260

(State or other jurisdiction of incorporation) (Commission File Number) (IRS Employer Identification No.)

​ ​ ​

​

5430 LBJ Freeway, Suite 1700, Dallas, Texas 75240-2620

(Address of principal executive offices) (Zip Code)

​ Registrant’s telephone number, including area code (972) 233-1700 ​

​

​

​

(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 (see General Instruction A.2): ​ ​

​

☐ 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 ​ NL ​ 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 (17 CFR §230.405) or Rule 12b-2 of the Securities Exchange Act of 1934 (17 CFR §240.12b-2). 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 2.02Results of Operations and Financial Condition. ​ The registrant hereby furnishes the information set forth in its press release entitled “NL Reports Third Quarter 2025 Results” issued on November 6, 2025, a copy of which is attached hereto as Exhibit 99.1 and incorporated herein by reference. ​ The press release the registrant furnishes as Exhibit 99.1 to this current report is not deemed “filed” for purposes of section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section.  Registration statements or other documents filed with the U.S. Securities and Exchange Commission shall not incorporate this information by reference, except as otherwise expressly stated in such filing. ​ ​ Item 9.01Financial Statements and Exhibits. ​ ​

​

​

​

(d) Exhibits ​ ​

​ ​ ​ ​

​ Item No.

Description

​ ​ ​ ​

​ 99.1 ​ Press release dated November 6, 2025 entitled “NL Reports Third Quarter 2025 Results” and issued by the registrant.

​ ​ ​ ​

​ 104 ​ Cover Page Interactive Data File (embedded within the Inline XBRL document)

​ ​ ​ ​

​ ​

SIGNATURE

​ 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. ​ ​

​

​

NL INDUSTRIES, INC.

​ (Registrant)

​ ​

​ ​

​ ​

Date: November 6, 2025 By: /s/Amy A. Samford

​ Amy A. Samford Executive Vice President and Chief Financial Officer

​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​