X0306 4 2022-06-01 0000072162 NL INDUSTRIES INC NL 0000024240 CONTRAN CORP 5430 LBJ FRWY SUITE 1700 DALLAS TX 75240-2620 0 0 1 0 0001599736 Simmons Lisa K 5430 LBJ FREEWAY SUITE 1700 DALLAS TX 75240-2620 0 0 1 0 0001257640 KRONOS WORLDWIDE INC 5430 LBJ FREEWAY SUITE 1700 DALLAS TX 75240-2620 0 0 1 0 0001600851 Harold C. Simmons Family Trust No. 2 5430 LBJ FREEWAY SUITE 1700 DALLAS TX 75240-2620 0 0 1 0 Common Stock $0.125 par value per share 2022-06-01 4 S 0 2000 8.23 D 0 I By Kronos Common Stock $0.125 par value per share 40387531 I By Valhi On June 1, 2022, the issuer, NL Industries, Inc. ("NL"), purchased 2,000 shares of its common stock, par value $0.125 per share, from Kronos Worldwide, Inc. ("Kronos") in a private transaction that was approved in advance by the independent directors of NL and Kronos. See Exhibit 99.1 to this statement for a description of the relationship of additional persons who may be deemed to have beneficially owned these shares. Directly held by Valhi, Inc. ("Valhi"). See Exhibit 99.1 to this statement for a description of the relationship of additional persons who may be deemed to beneficially own these shares. Exhibit Index 99.1 Additional Information Andrew B. Nace, Executive Vice President of Contran Corporation 2022-06-01 Andrew B. Nace, Executive Vice President of Kronos Worldwide, Inc. 2022-06-01 Andrew B. Nace, Attorney-in-fact for Lisa K. Simmons 2022-06-01 Ashley Tarleton, AVP & Trust Officer of Tolleson Private Bank, not in its individual capacity but solely as trustee of the Harold C. Simmons Family Trust No. 2 2022-06-01