X0508 4 2025-05-15 0000067716 MDU RESOURCES GROUP INC MDU 0002048128 Boese Dyke A. 1200 WEST CENTURY AVENUE BISMARCK ND 58503 1 CIO 0 Common Stock - 401(k) 2025-05-15 4 I 0 7748.6530 16.9900 A 17274.4173 I By Trustee Common Stock 3382.0000 D Common Stock 211.0000 I By Child The reporting person's 401(k) was inadvertently rebalanced on May 15, 2025, resulting in the inadvertent purchase of additional shares of the issuer's common stock on May 15, 2025. These shares are held in the name of the reporting person's child. The reporting person disclaims beneficial ownership of these securities, and the filing of this report is not an admission that the reporting person is the beneficial owner of these securities for purposes of Section 16 or for any other purpose, except to the extent of his pecuniary interest. Anthony D. Foti, Attorney-in-Fact for Dyke Boese 2025-07-16