MDU Resources Group, Inc.
US ˙ NYSE ˙ US5526901096

SecurityMDU / MDU Resources Group, Inc.
InstitutionCitadel Advisors Llc
ManagerKen Griffin
Latest Disclosed Ownership1,094,809 shares
Latest Disclosed Value $ 22,684,442
Citadel Advisors Llc ownership in MDU / MDU Resources Group, Inc.

On May 15, 2026 - Citadel Advisors Llc filed a 13F-HR form disclosing ownership of 1,094,809 shares of MDU Resources Group, Inc. (US:MDU) valued at $22,684,442 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 1,704,631 shares of MDU Resources Group, Inc.. This represents a change in shares of -35.77% during the quarter. The current value of the position is $22,728,235 USD.

Citadel Advisors Llc has a history of taking positions in derivatives of the underlying security (MDU) in the form of stock options. The firm currently holds call options representing 0 of underlying shares valued at $0 USD and put options representing 0 of underlying shares valued at $0 USD .

Note: prior versions of this page mistakenly stated that the share values represented the number of options, not the number of underlying shares. For more information on the data backing these reports, please see the SEC document Frequently Asked Questions About Form 13F.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Institutional Put/Call Ratios
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In addition to reporting standard equity and debt issues, institutions with more than 100MM assets under management must also disclose their put and call option holdings. Since put options generally indicate negative sentiment, and call options indicate positive sentiment, we can get a sense of the overall institutional sentiment by plotting the ratio of puts to calls. The chart to the right plots the historical put/call ratio for this instrument.

Using Put/Call Ratio as an indicator of investor sentiment overcomes one of the key deficiencies of using total institutional ownership, which is that a significant amount of assets under management are invested passively to track indices. Passively-managed funds do not typically buy options, so the put/call ratio indicator more closely tracks the sentiment of actively-managed funds.

MDU / MDU Resources Group, Inc. Historical Put/Call Ratio
Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-05-15 2026-03-31 13F MDU RES GROUP COM 552690109 1,094,809 -609,822 -35.77 22,684 -31.83 0.0032
2026-02-17 2025-12-31 13F MDU RES GROUP COM 552690109 1,704,631 526,332 44.67 33,274 58.56 0.0050
2025-11-14 2025-09-30 13F MDU RES GROUP COM 552690109 1,178,299 895,853 317.18 20,986 345.73 0.0032
2025-08-14 2025-06-30 13F MDU RES GROUP COM 552690109 282,446 233,932 482.19 4,708 474.15 0.0008
2025-05-15 2025-03-31 13F MDU RES GROUP COM 552690109 48,514 -142,654 -74.62 820 -76.19 0.0002
2025-02-14 2024-12-31 13F MDU RES GROUP COM 552690109 191,168 -861,595 -81.84 3,445 -88.06 0.0006
2024-11-14 2024-09-30 13F MDU RES GROUP COM 552690109 1,052,763 1,052,763 28,856 0.0056
2024-08-14 2024-06-30 13F MDU RES GROUP COM 552690109 0 -56,463 -100.00 0 -100.00
2024-05-15 2024-03-31 13F MDU RES GROUP COM 552690109 56,463 -1,506,010 -96.39 1,423 -95.40 0.0003
2024-02-14 2023-12-31 13F MDU RES GROUP COM 552690109 1,562,473 -341,527 -17.94 30,937 -17.02 0.0062
2023-11-14 2023-09-30 13F MDU RES GROUP COM 552690109 1,904,000 1,562,289 457.20 37,280 421.03 0.0080
2023-08-14 2023-06-30 13F MDU RES GROUP COM 552690109 341,711 -179,726 -34.47 7,155 -54.98 0.0015
2023-05-15 2023-03-31 13F MDU RES GROUP COM 552690109 521,437 -87,716 -14.40 15,893 -14.00 0.0035
2023-02-14 2022-12-31 13F MDU RES GROUP COM 552690109 609,153 239,909 64.97 18,482 83.00 0.0043
2022-11-14 2022-09-30 13F MDU RES GROUP COM 552690109 369,244 -406,724 -52.42 10,099 -51.78 0.0023
2022-08-15 2022-06-30 13F MDU RES GROUP COM 552690109 775,968 278,734 56.06 20,943 58.05 0.0054
2022-05-16 2022-03-31 13F MDU RES GROUP COM 552690109 497,234 442,153 802.73 13,251 679.93 0.0027
2022-02-14 2021-12-31 13F MDU RES GROUP COM 552690109 55,081 -43,870 -44.34 1,699 -42.11 0.0003
2021-11-15 2021-09-30 13F MDU RES GROUP Cmn 552690109 98,951 -541,398 -84.55 2,935 -85.38 0.0006
2021-08-16 2021-06-30 13F MDU RES GROUP COM 552690109 640,349 505,976 376.55 20,069 372.55 0.0045
2021-05-21 2021-03-31 13F/A-1 MDU RES GROUP COM 552690109 134,373 102,208 317.76 4,247 401.42 0.0010
2021-05-17 2021-03-31 13F MDU RES GROUP COM 552690109 134,373 102,208 4,247 0.0010
2021-02-16 2020-12-31 13F MDU RES GROUP COM 552690109 32,165 -4,917 -13.26 847 1.56 0.0002
2020-11-16 2020-09-30 13F MDU RES GROUP COM 552690109 37,082 -183,289 -83.17 834 -82.94 0.0002
2020-08-14 2020-06-30 13F MDU RES GROUP Cmn 552690109 220,371 -1,089,551 -83.18 4,888 -82.64 0.0017
2020-05-15 2020-03-31 13F MDU RES GROUP Cmn 552690109 1,309,922 -1,289,928 -49.62 28,164 -63.54 0.0127
2020-02-14 2019-12-31 13F MDU RES GROUP Cmn 552690109 2,599,850 -242,994 -8.55 77,242 -3.62 0.0335
2019-11-14 2019-09-30 13F MDU RES GROUP Cmn 552690109 2,842,844 -97,435 -3.31 80,140 5.64 0.0378
2019-08-14 2019-06-30 13F MDU RES GROUP Cmn 552690109 2,940,279 545,047 22.76 75,859 22.61 0.0348
2019-05-15 2019-03-31 13F MDU RES GROUP Cmn 552690109 2,395,232 252,035 11.76 61,869 21.09 0.0308
2019-02-14 2018-12-31 13F MDU RES GROUP Cmn 552690109 2,143,197 308,694 16.83 51,094 8.42 0.0280
2018-11-13 2018-09-30 13F MDU RES GROUP Cmn 552690109 1,834,503 106,343 6.15 47,128 -4.91 0.0211
2018-08-14 2018-06-30 13F/A-1 MDU RES GROUP Cmn 552690109 1,728,160 -253,706 -12.80 49,564 -11.19 0.0245
2018-08-10 2018-06-30 13F MDU RES GROUP Cmn 552690109 1,728,160 -253,706 49,564
2018-05-14 2018-03-31 13F/A-1 MDU RES GROUP Cmn 552690109 1,981,866 232,967 13.32 55,809 18.72 0.0307
2018-05-11 2018-03-31 13F MDU RES GROUP Cmn 552690109 1,981,866 232,967 55,809
2018-02-09 2017-12-31 13F MDU RES GROUP Cmn 552690109 1,748,899 172,500 10.94 47,010 14.92 0.0286
2017-11-09 2017-09-30 13F MDU RES GROUP Cmn 552690109 1,576,399 729,943 86.24 40,908 84.46 0.0314
2017-08-11 2017-06-30 13F MDU RES GROUP Cmn 552690109 846,456 134,867 18.95 22,177 13.87 0.0188
2017-05-12 2017-03-31 13F MDU RES GROUP Cmn 552690109 711,589 683,325 2,417.65 19,476 2,295.57 0.0178
2017-02-10 2016-12-31 13F MDU RES GROUP Cmn 552690109 28,264 28,264 -96.03 813 -95.83 0.0008
2016-11-10 2016-09-30 13F MDU RESOURCES GROUP INC CMN STK Cmn 552690109 0 -30,194 -100.00 0 -100.00
2017-01-31 2016-06-30 13F/A-1 MDU RES GROUP Cmn 552690109 30,194 -320,645 -91.39 725 -89.38 0.0008
2016-08-12 2016-06-30 13F MDU RESOURCES GROUP INC CMN STK Cmn 552690109 30,194 725
2017-01-31 2016-03-31 13F/A-1 MDU RES GROUP Cmn 552690109 350,839 187,156 114.34 6,828 127.68 0.0086
2016-05-13 2016-03-31 13F MDU RESOURCES GROUP INC CMN STK Cmn 552690109 350,839 6,828
2017-01-31 2015-12-31 13F/A-1 MDU RES GROUP Cmn 552690109 163,683 -105,554 -39.20 2,999 -35.24 0.0033
2016-02-12 2015-12-31 13F MDU RESOURCES GROUP INC CMN STK Cmn 552690109 163,683 2,999
2015-11-16 2015-09-30 13F MDU RESOURCES GROUP INC CMN STK Cmn 552690109 269,237 -12,289 -4.37 4,631 -15.77 0.0045
2015-08-14 2015-06-30 13F MDU RESOURCES GROUP INC CMN STK Cmn 552690109 281,526 84,472 42.87 5,498 30.75 0.0048
2015-05-15 2015-03-31 13F MDU RESOURCES GROUP INC CMN STK Cmn 552690109 197,054 -60,438 -23.47 4,205 -30.51 0.0047
2015-02-17 2014-12-31 13F MDU RESOURCES GROUP INC CMN STK Cmn 552690109 257,492 173,699 207.30 6,051 159.70 0.0073
2014-11-14 2014-09-30 13F MDU RESOURCES GROUP INC CMN STK Cmn 552690109 83,793 -10,267 -10.92 2,330 -29.42 0.0029
2014-08-14 2014-06-30 13F MDU RESOURCES GROUP INC CMN STK Cmn 552690109 94,060 -13,678 -12.70 3,301 -10.71 0.0045
2014-05-15 2014-03-31 13F MDU RESOURCES GROUP INC CMN STK Cmn 552690109 107,738 41,444 62.52 3,697 99.41 0.0051
2013-11-14 2013-09-30 13F MDU RESOURCES GROUP INC CMN STK Cmn 552690109 66,294 -395,782 -85.65 1,854 -84.52 0.0028
2013-08-14 2013-06-30 13F MDU RESOURCES GROUP INC CMN STK Cmn 552690109 462,076 462,076 11,973 0.0207
Disclosed Call Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share
Price
Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2026-05-15 2026-03-31 13F MDU RES GROUP COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2026-02-17 2025-12-31 13F MDU RES GROUP COM Call 11,300 221 n/a n/a n/a
2025-08-14 2025-06-30 13F MDU RES GROUP COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2025-05-15 2025-03-31 13F MDU RES GROUP COM Call 53,900 -40.04 911 -43.73 n/a n/a n/a
2025-02-14 2024-12-31 13F MDU RES GROUP COM Call 89,900 105.72 1,620 35.25 n/a n/a n/a
2024-11-14 2024-09-30 13F MDU RES GROUP COM Call 43,700 110.10 1,198 129.31 n/a n/a n/a
2024-08-14 2024-06-30 13F MDU RES GROUP COM Call 20,800 -45.55 522 -45.74 n/a n/a n/a
2024-05-15 2024-03-31 13F MDU RES GROUP COM Call 38,200 72.85 963 120.14 n/a n/a n/a
2024-02-14 2023-12-31 13F MDU RES GROUP COM Call 22,100 1.38 438 2.58 n/a n/a n/a
2023-11-14 2023-09-30 13F MDU RES GROUP COM Call 21,800 -70.86 427 -72.80 n/a n/a n/a
2023-08-14 2023-06-30 13F MDU RES GROUP COM Call 74,800 206.56 1,566 110.77 n/a n/a n/a
2023-05-15 2023-03-31 13F MDU RES GROUP COM Call 24,400 34.07 744 34.60 n/a n/a n/a
2023-02-14 2022-12-31 13F MDU RES GROUP COM Call 18,200 16.67 552 29.27 n/a n/a n/a
2022-11-14 2022-09-30 13F MDU RES GROUP COM Call 15,600 13.87 427 15.41 n/a n/a n/a
2022-08-15 2022-06-30 13F MDU RES GROUP COM Call 13,700 0.00 370 1.37 n/a n/a n/a
2022-05-16 2022-03-31 13F MDU RES GROUP COM Call 13,700 -15.43 365 -27.00 n/a n/a n/a
2022-02-14 2021-12-31 13F MDU RES GROUP COM Call 16,200 107.69 500 116.45 n/a n/a n/a
2021-11-15 2021-09-30 13F MDU RES GROUP Cmn Call 7,800 -63.38 231 -65.42 n/a n/a n/a
2021-08-16 2021-06-30 13F MDU RES GROUP COM Call 21,300 -15.81 668 -16.50 n/a n/a n/a
2021-05-21 2021-03-31 13F/A MDU RES GROUP COM Call 25,300 52.41 800 83.07 n/a n/a n/a
2021-05-17 2021-03-31 13F MDU RES GROUP COM Call 25,300 800 n/a n/a n/a
2021-02-16 2020-12-31 13F MDU RES GROUP COM Call 16,600 -43.92 437 -34.38 n/a n/a n/a
2020-11-16 2020-09-30 13F MDU RES GROUP COM Call 29,600 81.60 666 83.98 n/a n/a n/a
2020-08-14 2020-06-30 13F MDU RES GROUP Cmn Call 16,300 -39.63 362 -37.69 n/a n/a n/a
2020-05-15 2020-03-31 13F MDU RES GROUP Cmn Call 27,000 49.17 581 7.99 n/a n/a n/a
2020-02-14 2019-12-31 13F MDU RES GROUP Cmn Call 18,100 0.00 538 5.49 n/a n/a n/a
2019-11-14 2019-09-30 13F MDU RES GROUP Cmn Call 18,100 129.11 510 150.00 n/a n/a n/a
2019-08-14 2019-06-30 13F MDU RES GROUP Cmn Call 7,900 -13.19 204 -13.19 n/a n/a n/a
2019-05-15 2019-03-31 13F MDU RES GROUP Cmn Call 9,100 -31.06 235 -25.40 n/a n/a n/a
2019-02-14 2018-12-31 13F MDU RES GROUP Cmn Call 13,200 28.16 315 18.87 n/a n/a n/a
2018-11-13 2018-09-30 13F MDU RES GROUP Cmn Call 10,300 265 n/a n/a n/a
2017-02-10 2016-12-31 13F MDU RESOURCES GROUP INC CMN STK Cmn Call 0 -100.00 0 -100.00 n/a n/a n/a
2017-01-31 2016-09-30 13F/A MDU RES GROUP Cmn Call 9,300 237 n/a n/a n/a
2016-11-10 2016-09-30 13F MDU RESOURCES GROUP INC CMN STK Cmn Call 9,300 237 n/a n/a n/a
2016-05-13 2016-03-31 13F MDU RESOURCES GROUP INC CMN STK Cmn Call 0 -100.00 0 -100.00 n/a n/a n/a
2017-01-31 2015-12-31 13F/A MDU RES GROUP Cmn Call 10,200 183.33 187 201.61 n/a n/a n/a
2016-02-12 2015-12-31 13F MDU RESOURCES GROUP INC CMN STK Cmn Call 10,200 187 n/a n/a n/a
2015-11-16 2015-09-30 13F MDU RESOURCES GROUP INC CMN STK Cmn Call 3,600 -16.28 62 -26.19 n/a n/a n/a
2015-08-14 2015-06-30 13F MDU RESOURCES GROUP INC CMN STK Cmn Call 4,300 -54.26 84 -58.21 n/a n/a n/a
2015-05-15 2015-03-31 13F MDU RESOURCES GROUP INC CMN STK Cmn Call 9,400 201 n/a n/a n/a
Disclosed Put Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share Price Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2025-08-14 2025-06-30 13F MDU RES GROUP COM Put 0 -100.00 0 -100.00 n/a n/a n/a
2025-05-15 2025-03-31 13F MDU RES GROUP COM Put 9,100 -2.15 154 -8.38 n/a n/a n/a
2025-02-14 2024-12-31 13F MDU RES GROUP COM Put 9,300 69.09 168 11.33 n/a n/a n/a
2024-11-14 2024-09-30 13F MDU RES GROUP COM Put 5,500 96.43 151 114.29 n/a n/a n/a
2024-08-14 2024-06-30 13F MDU RES GROUP COM Put 2,800 -65.00 70 -65.17 n/a n/a n/a
2024-05-15 2024-03-31 13F MDU RES GROUP COM Put 8,000 -25.23 202 -4.74 n/a n/a n/a
2024-02-14 2023-12-31 13F MDU RES GROUP COM Put 10,700 -43.68 212 -43.28 n/a n/a n/a
2023-11-14 2023-09-30 13F MDU RES GROUP COM Put 19,000 65.22 372 55.00 n/a n/a n/a
2023-08-14 2023-06-30 13F MDU RES GROUP COM Put 11,500 51.32 241 3.90 n/a n/a n/a
2023-05-15 2023-03-31 13F MDU RES GROUP COM Put 7,600 660.00 232 670.00 n/a n/a n/a
2023-02-14 2022-12-31 13F MDU RES GROUP COM Put 1,000 30 n/a n/a n/a
2022-08-15 2022-06-30 13F MDU RES GROUP COM Put 0 -100.00 0 -100.00 n/a n/a n/a
2022-05-16 2022-03-31 13F MDU RES GROUP COM Put 18,800 54.10 501 33.24 n/a n/a n/a
2022-02-14 2021-12-31 13F MDU RES GROUP COM Put 12,200 -74.48 376 -73.48 n/a n/a n/a
2021-11-15 2021-09-30 13F MDU RES GROUP Cmn Put 47,800 64.26 1,418 55.48 n/a n/a n/a
2021-08-16 2021-06-30 13F MDU RES GROUP COM Put 29,100 69.19 912 67.65 n/a n/a n/a
2021-05-21 2021-03-31 13F/A MDU RES GROUP COM Put 17,200 21.13 544 45.45 n/a n/a n/a
2021-05-17 2021-03-31 13F MDU RES GROUP COM Put 17,200 544 n/a n/a n/a
2021-02-16 2020-12-31 13F MDU RES GROUP COM Put 14,200 1.43 374 18.73 n/a n/a n/a
2020-11-16 2020-09-30 13F MDU RES GROUP COM Put 14,000 19.66 315 21.15 n/a n/a n/a
2020-08-14 2020-06-30 13F MDU RES GROUP Cmn Put 11,700 260 n/a n/a n/a
2016-05-13 2016-03-31 13F MDU RESOURCES GROUP INC CMN STK Cmn Put 0 -100.00 0 -100.00 n/a n/a n/a
2017-01-31 2015-12-31 13F/A MDU RES GROUP Cmn Put 10,300 -52.97 189 -49.87 n/a n/a n/a
2016-02-12 2015-12-31 13F MDU RESOURCES GROUP INC CMN STK Cmn Put 10,300 189 n/a n/a n/a
2015-11-16 2015-09-30 13F MDU RESOURCES GROUP INC CMN STK Cmn Put 21,900 38.61 377 22.01 n/a n/a n/a
2015-08-14 2015-06-30 13F MDU RESOURCES GROUP INC CMN STK Cmn Put 15,800 953.33 309 865.63 n/a n/a n/a
2015-05-15 2015-03-31 13F MDU RESOURCES GROUP INC CMN STK Cmn Put 1,500 32 n/a n/a n/a
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.