UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM SD

SPECIALIZED DISCLOSURE REPORT

MDU Resources Group, Inc.

(Exact name of registrant as specified in its charter)

Delaware	1-03480	30-1133956
(State or other jurisdiction of Incorporation)	(Commission File Number)	(I.R.S. Employer Identification No.)

1200 West Century Avenue

P.O. Box 5650

Bismarck, North Dakota 58506-5650

(Address of principal executive offices)

(Zip Code)

Jason L. Vollmer

(701) 530-1000

(Name and telephone number, including area code,

of the person to contact in connection with this report)

Check the appropriate box to indicate the rule pursuant to which this form is being filed, and provide the period to which the information in this form applies:

x Rule 13p-1 under the Securities Exchange Act (17 CFR 240.13p-1) for the reporting period from January 1 to December 31, 2020.

Section 1 - Conflict Minerals Disclosure

Items 1.01 and 1.02 Conflict Minerals Disclosure and Report, Exhibit

Conflict Minerals Disclosure

A copy of MDU Resources Group, Inc.’s (the “Company’s”) Conflict Minerals Report for the 2020 reporting period is filed as Exhibit 1.01 hereto and is publicly available at https://www.mdu.com/conflict-minerals. The content of the Company’s website referred to in this Specialized Disclosure Report on Form SD is included for general information only and is not incorporated by reference into this Form SD.

Section 2 – Exhibits

Item 2.01 Exhibits

Exhibit 1.01 - Conflict Minerals Report as required by Items 1.01 and 1.02 of this Form SD.

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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 duly authorized undersigned.

Date: May 27, 2021.

MDU RESOURCES GROUP, INC.
By:	/s/ Jason L. Vollmer
	Jason L. Vollmer
	Vice President and Chief Financial Officer

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