144 0001672978 XXXXXXXX LIVE 0000071829 NPK International Inc. 001-02960 9320 Lakeside Boulevard Suite 100 The Woodlands TX 77381 (281)362-6800 MATTHEW LANIGAN Director Officer Common Morgan Stanley Smith Barney LLC Executive Financial Services

1 New York Plaza 8th Floor New York NY 10004

69896 698960.00 84432766 08/22/2025 NYSE Common 08/22/2025 Exercise of Stock Options Issuer N 69896 08/22/2025 Cash Y The securities to be sold were and will be received upon the exercise of stock options over the next three months. The dates of acquisition and payment were and will be the dates of exercise/sale. 08/22/2025 05/23/2025 /s/ Matthew Lanigan