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[S-3ASR] MDU Resources Group, Inc. SEC Filing

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Filing Sentiment
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S-3ASR
Rhea-AI Filing Summary

Corebridge Financial (NYSE: CRBG) filed a Rule 424(b)(7) prospectus for a secondary offering of 30 million shares—about 5.6 % of outstanding stock—being sold exclusively by American International Group (AIG). The shares are priced at $33.65, implying gross proceeds of $1.01 billion to AIG and no cash to Corebridge. Morgan Stanley is sole underwriter and has a 30-day option to purchase up to 4.5 million additional shares for overallotments. If fully exercised, AIG’s ownership will fall to 14.74 % from 21.15 %; without the option it drops to 15.58 %. Blackstone and Nippon Life will continue to hold 11.51 % and 22.65 %, respectively.

The filing stresses that Corebridge is not issuing new shares, so there is no dilution. The company reiterates its $0.24 quarterly cash dividend (next payable 30 Sep 2025) and its expanded $5 billion share-repurchase authorization, of which $3.9 billion remains after buying back 4.5 million shares for $159 million in July � Aug 2025.

Key risk factors include market volatility from the block sale, continuing overhang from AIG’s remaining stake, and general insurance-industry exposures. Delivery of the shares is expected on 8 Aug 2025.

Corebridge Financial (NYSE: CRBG) ha depositato un prospetto Rule 424(b)(7) per un'offerta secondaria di 30 milioni di azioni—circa il 5,6% del capitale sociale in circolazione—vendute esclusivamente da American International Group (AIG). Le azioni sono quotate a 33,65 dollari, con un ricavo lordo stimato di 1,01 miliardi di dollari per AIG e nessun incasso per Corebridge. Morgan Stanley è l'unico sottoscrittore e dispone di un'opzione di 30 giorni per acquistare fino a 4,5 milioni di azioni aggiuntive per l'over-allotment. Se l'opzione verrà esercitata completamente, la quota di AIG scenderà dal 21,15% al 14,74%; senza l'opzione, si ridurrà al 15,58%. Blackstone e Nippon Life manterranno rispettivamente l'11,51% e il 22,65%.

Il deposito sottolinea che Corebridge non emette nuove azioni, quindi non c'è diluizione. La società conferma il dividendo trimestrale in contanti di 0,24 dollari (prossimo pagamento il 30 settembre 2025) e l'ampliamento dell'autorizzazione al riacquisto di azioni per 5 miliardi di dollari, di cui rimangono 3,9 miliardi dopo il riacquisto di 4,5 milioni di azioni per 159 milioni di dollari tra luglio e agosto 2025.

I principali fattori di rischio includono la volatilità di mercato dovuta alla vendita in blocco, la pressione continua derivante dalla quota residua di AIG e le esposizioni generali del settore assicurativo. La consegna delle azioni è prevista per l'8 agosto 2025.

Corebridge Financial (NYSE: CRBG) presentó un prospecto Rule 424(b)(7) para una oferta secundaria de 30 millones de acciones—aproximadamente el 5,6 % de las acciones en circulación—vendidas exclusivamente por American International Group (AIG). Las acciones tienen un precio de 33,65 dólares, lo que implica ingresos brutos de 1.010 millones de dólares para AIG y ningún ingreso para Corebridge. Morgan Stanley es el único suscriptor y tiene una opción de 30 días para comprar hasta 4,5 millones de acciones adicionales para sobreasignación. Si se ejerce completamente, la participación de AIG caerá del 21,15 % al 14,74 %; sin la opción baja al 15,58 %. Blackstone y Nippon Life seguirán manteniendo el 11,51 % y el 22,65 %, respectivamente.

El documento enfatiza que Corebridge no está emitiendo nuevas acciones, por lo que no hay dilución. La compañía reitera su dividendo trimestral en efectivo de 0,24 dólares (próximo pago el 30 de septiembre de 2025) y su ampliada autorización de recompra de acciones por 5.000 millones de dólares, de los cuales quedan 3.900 millones después de recomprar 4,5 millones de acciones por 159 millones de dólares entre julio y agosto de 2025.

Los principales factores de riesgo incluyen la volatilidad del mercado por la venta en bloque, la presión continua por la participación restante de AIG y las exposiciones generales de la industria aseguradora. La entrega de las acciones está prevista para el 8 de agosto de 2025.

Corebridge Financial (NYSE: CRBG)ëŠ� American International Group (AIG)ì� 단ë…으로 매ê°í•˜ëŠ” ì•� 5.6%ì—� 해당하는 3,000ë§� ì£¼ì˜ 2ì°� 공모ë¥� 위한 Rule 424(b)(7) 투ìžì„¤ëª…서를 제출했습니다. 주당 ê°€ê²©ì€ 33.65달러ë¡�, AIGì—� ì•� 10ì–� 1천만 달러ì� ì´ìˆ˜ìµì„ ì˜ë¯¸í•˜ë©° Corebridgeì—는 현금ì� 유입ë˜ì§€ 않습니다. Morgan Stanleyê°€ ë‹¨ë… ì¸ìˆ˜ì¸ìœ¼ë¡� 30ì¼ê°„ 최대 450ë§� ì£� 추가 매입 옵션ì� 보유하고 있습니다. 옵션ì� ì „ë¶€ 행사ë˜ë©´ AIGì� ì§€ë¶„ìœ¨ì€ 21.15%ì—서 14.74%ë¡� ê°ì†Œí•˜ë©°, 옵션 미행ì‚� ì‹� 15.58%ë¡� 낮아집니ë‹�. Blackstoneê³� Nippon LifeëŠ� ê°ê° 11.51%와 22.65%ì� ì§€ë¶„ì„ ìœ ì§€í•©ë‹ˆë‹�.

해당 신고서는 Corebridgeê°€ ì‹ ê·œ 주ì‹ì� 발행하지 않으므ë¡� í¬ì„ 효과가 ì—†ìŒì� 강조합니ë‹�. 회사ëŠ� 분기ë³� 현금 배당ê¸� 0.24달러 (ë‹¤ìŒ ì§€ê¸‰ì¼ 2025ë…� 9ì›� 30ì�)와 50ì–� 달러 규모ì� ì£¼ì‹ ìž¬ë§¤ìž� ìŠ¹ì¸ í•œë„ í™•ëŒ€ë¥� 재확ì¸í–ˆìœ¼ë©°, 2025ë…� 7ì›”~8ì›”ì— 450ë§� 주를 1ì–� 5,900ë§� 달러ì—� 매입í•� í›� 39ì–� 달러가 남아 있습니다.

주요 위험 ìš”ì¸ìœ¼ë¡œëŠ� 대ëŸ� 매ë„ì—� 따른 시장 ë³€ë™ì„±, AIG 잔여 ì§€ë¶„ì˜ ì§€ì†ì  ë¶€ë‹�, ë³´í—˜ ì‚°ì—… ì „ë°˜ì� 노출 ë“±ì´ ìžˆìŠµë‹ˆë‹¤. ì£¼ì‹ ì¸ë„ëŠ� 2025ë…� 8ì›� 8ì¼ë¡œ 예정ë˜ì–´ 있습니다.

Corebridge Financial (NYSE : CRBG) a déposé un prospectus Rule 424(b)(7) pour une offre secondaire de 30 millions d'actions—soit environ 5,6 % du capital en circulation—vendues exclusivement par American International Group (AIG). Les actions sont fixées à 33,65 dollars, ce qui implique un produit brut de 1,01 milliard de dollars pour AIG et aucun encaissement pour Corebridge. Morgan Stanley est le seul souscripteur et dispose d'une option de 30 jours pour acheter jusqu'à 4,5 millions d'actions supplémentaires en cas de surallocation. Si l'option est entièrement exercée, la participation d'AIG passera de 21,15 % à 14,74 % ; sans l'option, elle descend à 15,58 %. Blackstone et Nippon Life continueront de détenir respectivement 11,51 % et 22,65 %.

Le dépôt souligne que Corebridge n'émet pas de nouvelles actions, il n'y a donc pas de dilution. La société réitère son dividende trimestriel en espèces de 0,24 $ (prochain paiement le 30 septembre 2025) et son autorisation élargie de rachat d'actions de 5 milliards de dollars, dont 3,9 milliards restent disponibles après le rachat de 4,5 millions d'actions pour 159 millions de dollars entre juillet et août 2025.

Les principaux facteurs de risque comprennent la volatilité du marché liée à la vente en bloc, la pression persistante de la participation restante d'AIG et les expositions générales du secteur de l'assurance. La livraison des actions est prévue pour le 8 août 2025.

Corebridge Financial (NYSE: CRBG) hat einen Rule 424(b)(7) Prospekt für ein Sekundärangebot von 30 Millionen Aktien—etwa 5,6 % des ausstehenden Aktienkapitals—eingereicht, die ausschließlich von American International Group (AIG) verkauft werden. Die Aktien sind zu 33,65 USD je Aktie bewertet, was Bruttoerlöse von 1,01 Milliarden USD für AIG bedeutet, Corebridge erhält keinen Erlös. Morgan Stanley ist alleiniger Underwriter und hat eine 30-tägige Option, bis zu 4,5 Millionen zusätzliche Aktien für Mehrzuteilungen zu kaufen. Wird die Option vollständig ausgeübt, sinkt der Anteil von AIG von 21,15 % auf 14,74 %; ohne Option auf 15,58 %. Blackstone und Nippon Life halten weiterhin 11,51 % bzw. 22,65 %.

Die Einreichung betont, dass Corebridge keine neuen Aktien ausgibt, daher keine Verwässerung stattfindet. Das Unternehmen bestätigt seine vierteljährliche Bardividende von 0,24 USD (nächste Zahlung am 30. September 2025) und die erweiterte Aktienrückkaufgenehmigung über 5 Milliarden USD, von der nach dem Rückkauf von 4,5 Millionen Aktien für 159 Millionen USD im Juli–August 2025 noch 3,9 Milliarden USD verbleiben.

Wesentliche Risikofaktoren sind die Marktvolatilität durch den Blockverkauf, der anhaltende Überhang der verbleibenden AIG-Beteiligung und allgemeine Risiken der Versicherungsbranche. Die Lieferung der Aktien wird für den 8. August 2025 erwartet.

Positive
  • No dilution: shares come from AIG, leaving Corebridge’s EPS and capital ratios unaffected.
  • Expanded $5 billion repurchase plan with $3.9 billion still available offers downside support.
  • Consistent cash dividend of $0.24 per quarter signals stable cash generation.
  • AIG ownership falls, reducing legacy-parent influence and moving toward a cleaner float.
Negative
  • Technical supply pressure: 30 million shares (+ optional 4.5 million) may weigh on price short-term.
  • Overhang persists: AIG will still hold ~15 % (â‰�80 million shares) post-offering.
  • No primary proceeds: company gains no additional capital to deploy for growth or debt reduction.

Insights

TL;DR: Pure secondary sale—no dilution, but supply overhang persists and may pressure near-term price.

The transaction is strictly a liquidity event for AIG, shrinking its stake by ~5.6 pp and widening Corebridge’s float. Because Corebridge receives no proceeds, capital structure and EPS remain unchanged—fundamentally neutral. However, 30 million shares (~$1 billion) hitting the market can create technical weakness, especially given a 30-day lock-up that is relatively short. Management can offset some pressure via its large remaining $3.9 billion buy-back authority, which equates to roughly 14 % of current market cap at the $34 range. From an ECM standpoint, the filing re-opens the path for eventual full AIG exit, gradually reducing the control discount.

TL;DR: Dividend integrity and buy-back capacity are intact; yield investors see limited impact.

The deal neither affects payout capacity nor leverages the balance sheet. The steady $0.24 quarterly dividend (�2.8 % forward yield) and ongoing buy-backs remain the key return drivers. Reduced sponsor ownership lowers governance risk over time, a positive for long-term holders. Nonetheless, the sizeable free-float increase and residual 15 % AIG position maintain some overhang, warranting cautious sizing until supply is absorbed. Overall, fundamentals unchanged; market impact hinges on depth of demand and management’s buy-back pace.

Corebridge Financial (NYSE: CRBG) ha depositato un prospetto Rule 424(b)(7) per un'offerta secondaria di 30 milioni di azioni—circa il 5,6% del capitale sociale in circolazione—vendute esclusivamente da American International Group (AIG). Le azioni sono quotate a 33,65 dollari, con un ricavo lordo stimato di 1,01 miliardi di dollari per AIG e nessun incasso per Corebridge. Morgan Stanley è l'unico sottoscrittore e dispone di un'opzione di 30 giorni per acquistare fino a 4,5 milioni di azioni aggiuntive per l'over-allotment. Se l'opzione verrà esercitata completamente, la quota di AIG scenderà dal 21,15% al 14,74%; senza l'opzione, si ridurrà al 15,58%. Blackstone e Nippon Life manterranno rispettivamente l'11,51% e il 22,65%.

Il deposito sottolinea che Corebridge non emette nuove azioni, quindi non c'è diluizione. La società conferma il dividendo trimestrale in contanti di 0,24 dollari (prossimo pagamento il 30 settembre 2025) e l'ampliamento dell'autorizzazione al riacquisto di azioni per 5 miliardi di dollari, di cui rimangono 3,9 miliardi dopo il riacquisto di 4,5 milioni di azioni per 159 milioni di dollari tra luglio e agosto 2025.

I principali fattori di rischio includono la volatilità di mercato dovuta alla vendita in blocco, la pressione continua derivante dalla quota residua di AIG e le esposizioni generali del settore assicurativo. La consegna delle azioni è prevista per l'8 agosto 2025.

Corebridge Financial (NYSE: CRBG) presentó un prospecto Rule 424(b)(7) para una oferta secundaria de 30 millones de acciones—aproximadamente el 5,6 % de las acciones en circulación—vendidas exclusivamente por American International Group (AIG). Las acciones tienen un precio de 33,65 dólares, lo que implica ingresos brutos de 1.010 millones de dólares para AIG y ningún ingreso para Corebridge. Morgan Stanley es el único suscriptor y tiene una opción de 30 días para comprar hasta 4,5 millones de acciones adicionales para sobreasignación. Si se ejerce completamente, la participación de AIG caerá del 21,15 % al 14,74 %; sin la opción baja al 15,58 %. Blackstone y Nippon Life seguirán manteniendo el 11,51 % y el 22,65 %, respectivamente.

El documento enfatiza que Corebridge no está emitiendo nuevas acciones, por lo que no hay dilución. La compañía reitera su dividendo trimestral en efectivo de 0,24 dólares (próximo pago el 30 de septiembre de 2025) y su ampliada autorización de recompra de acciones por 5.000 millones de dólares, de los cuales quedan 3.900 millones después de recomprar 4,5 millones de acciones por 159 millones de dólares entre julio y agosto de 2025.

Los principales factores de riesgo incluyen la volatilidad del mercado por la venta en bloque, la presión continua por la participación restante de AIG y las exposiciones generales de la industria aseguradora. La entrega de las acciones está prevista para el 8 de agosto de 2025.

Corebridge Financial (NYSE: CRBG)ëŠ� American International Group (AIG)ì� 단ë…으로 매ê°í•˜ëŠ” ì•� 5.6%ì—� 해당하는 3,000ë§� ì£¼ì˜ 2ì°� 공모ë¥� 위한 Rule 424(b)(7) 투ìžì„¤ëª…서를 제출했습니다. 주당 ê°€ê²©ì€ 33.65달러ë¡�, AIGì—� ì•� 10ì–� 1천만 달러ì� ì´ìˆ˜ìµì„ ì˜ë¯¸í•˜ë©° Corebridgeì—는 현금ì� 유입ë˜ì§€ 않습니다. Morgan Stanleyê°€ ë‹¨ë… ì¸ìˆ˜ì¸ìœ¼ë¡� 30ì¼ê°„ 최대 450ë§� ì£� 추가 매입 옵션ì� 보유하고 있습니다. 옵션ì� ì „ë¶€ 행사ë˜ë©´ AIGì� ì§€ë¶„ìœ¨ì€ 21.15%ì—서 14.74%ë¡� ê°ì†Œí•˜ë©°, 옵션 미행ì‚� ì‹� 15.58%ë¡� 낮아집니ë‹�. Blackstoneê³� Nippon LifeëŠ� ê°ê° 11.51%와 22.65%ì� ì§€ë¶„ì„ ìœ ì§€í•©ë‹ˆë‹�.

해당 신고서는 Corebridgeê°€ ì‹ ê·œ 주ì‹ì� 발행하지 않으므ë¡� í¬ì„ 효과가 ì—†ìŒì� 강조합니ë‹�. 회사ëŠ� 분기ë³� 현금 배당ê¸� 0.24달러 (ë‹¤ìŒ ì§€ê¸‰ì¼ 2025ë…� 9ì›� 30ì�)와 50ì–� 달러 규모ì� ì£¼ì‹ ìž¬ë§¤ìž� ìŠ¹ì¸ í•œë„ í™•ëŒ€ë¥� 재확ì¸í–ˆìœ¼ë©°, 2025ë…� 7ì›”~8ì›”ì— 450ë§� 주를 1ì–� 5,900ë§� 달러ì—� 매입í•� í›� 39ì–� 달러가 남아 있습니다.

주요 위험 ìš”ì¸ìœ¼ë¡œëŠ� 대ëŸ� 매ë„ì—� 따른 시장 ë³€ë™ì„±, AIG 잔여 ì§€ë¶„ì˜ ì§€ì†ì  ë¶€ë‹�, ë³´í—˜ ì‚°ì—… ì „ë°˜ì� 노출 ë“±ì´ ìžˆìŠµë‹ˆë‹¤. ì£¼ì‹ ì¸ë„ëŠ� 2025ë…� 8ì›� 8ì¼ë¡œ 예정ë˜ì–´ 있습니다.

Corebridge Financial (NYSE : CRBG) a déposé un prospectus Rule 424(b)(7) pour une offre secondaire de 30 millions d'actions—soit environ 5,6 % du capital en circulation—vendues exclusivement par American International Group (AIG). Les actions sont fixées à 33,65 dollars, ce qui implique un produit brut de 1,01 milliard de dollars pour AIG et aucun encaissement pour Corebridge. Morgan Stanley est le seul souscripteur et dispose d'une option de 30 jours pour acheter jusqu'à 4,5 millions d'actions supplémentaires en cas de surallocation. Si l'option est entièrement exercée, la participation d'AIG passera de 21,15 % à 14,74 % ; sans l'option, elle descend à 15,58 %. Blackstone et Nippon Life continueront de détenir respectivement 11,51 % et 22,65 %.

Le dépôt souligne que Corebridge n'émet pas de nouvelles actions, il n'y a donc pas de dilution. La société réitère son dividende trimestriel en espèces de 0,24 $ (prochain paiement le 30 septembre 2025) et son autorisation élargie de rachat d'actions de 5 milliards de dollars, dont 3,9 milliards restent disponibles après le rachat de 4,5 millions d'actions pour 159 millions de dollars entre juillet et août 2025.

Les principaux facteurs de risque comprennent la volatilité du marché liée à la vente en bloc, la pression persistante de la participation restante d'AIG et les expositions générales du secteur de l'assurance. La livraison des actions est prévue pour le 8 août 2025.

Corebridge Financial (NYSE: CRBG) hat einen Rule 424(b)(7) Prospekt für ein Sekundärangebot von 30 Millionen Aktien—etwa 5,6 % des ausstehenden Aktienkapitals—eingereicht, die ausschließlich von American International Group (AIG) verkauft werden. Die Aktien sind zu 33,65 USD je Aktie bewertet, was Bruttoerlöse von 1,01 Milliarden USD für AIG bedeutet, Corebridge erhält keinen Erlös. Morgan Stanley ist alleiniger Underwriter und hat eine 30-tägige Option, bis zu 4,5 Millionen zusätzliche Aktien für Mehrzuteilungen zu kaufen. Wird die Option vollständig ausgeübt, sinkt der Anteil von AIG von 21,15 % auf 14,74 %; ohne Option auf 15,58 %. Blackstone und Nippon Life halten weiterhin 11,51 % bzw. 22,65 %.

Die Einreichung betont, dass Corebridge keine neuen Aktien ausgibt, daher keine Verwässerung stattfindet. Das Unternehmen bestätigt seine vierteljährliche Bardividende von 0,24 USD (nächste Zahlung am 30. September 2025) und die erweiterte Aktienrückkaufgenehmigung über 5 Milliarden USD, von der nach dem Rückkauf von 4,5 Millionen Aktien für 159 Millionen USD im Juli–August 2025 noch 3,9 Milliarden USD verbleiben.

Wesentliche Risikofaktoren sind die Marktvolatilität durch den Blockverkauf, der anhaltende Überhang der verbleibenden AIG-Beteiligung und allgemeine Risiken der Versicherungsbranche. Die Lieferung der Aktien wird für den 8. August 2025 erwartet.

As filed with the Securities and Exchange Commission on August 7, 2025

Registration Statement No. 333-

 

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

___________________________________

FORM S-3

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

___________________________________

MDU RESOURCES GROUP, INC.

(Exact name of registrant as specified in its charter)

Delaware 30-1133956

(State or other jurisdiction of

incorporation or organization)

(I.R.S. Employer Identification No.)

1200 West Century Avenue
P.O. Box 5650
Bismarck, North Dakota 58506
(701) 530-1000

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices) 

Anthony D. Foti
Chief Legal Officer
and Corporate Secretary

MDU Resources Group, Inc.
1200 West Century Avenue
P.O. Box 5650
Bismarck, North Dakota 58506-5650
(701) 530-1000
Jason Day
Jonathan S. Schulman
Perkins Coie LLP
1900 Sixteenth Street, Suite 1400
Denver, Colorado 80202
(303) 291-2300

 

 

(Names and addresses, including zip codes, and telephone numbers, including area codes, of agents for service)

Approximate date of commencement of proposed sale to the public:

From time to time after the effective date of this registration statement as determined by market conditions and other factors.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box: ☐

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box: ☒

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ☐

If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. ☒

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth

company” in Rule 12b-2 of the Exchange Act.

Large accelerated filer Accelerated filer
Non-accelerated filer Smaller reporting company
Emerging growth company

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

PROSPECTUS

MDU RESOURCES GROUP, INC.

Common Stock

Preferred Stock

Debt Securities

Warrants

Purchase Contracts

Units

We may offer from time to time any combination of the securities described in this prospectus in one or more offerings and in amounts authorized from time to time. We will provide the specific terms of our securities, including their offering prices, in supplements to this prospectus. The supplements may also add, update or change information contained in this prospectus. You should read this prospectus and any supplements carefully before you invest. The securities may be sold to or through one or more underwriters, dealers or agents, or directly to investors, on a continuous or delayed basis. See “Plan of Distribution.”

Our common stock is listed on the New York Stock Exchange (the “NYSE”) and trades under the symbol “MDU.” The last reported sale price of our common stock on the NYSE on August 6, 2025 was $17.49 per share.

___________________________________

Investing in our securities involves risks. See “Risk Factors” on page 2 of this prospectus, and any applicable prospectus supplement, and in the documents that are incorporated by reference herein.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

___________________________________

The date of this prospectus is August 7, 2025.

TABLE OF CONTENTS

Page
ABOUT THIS PROSPECTUS i
CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS ii
MDU RESOURCES GROUP, INC. 1
RISK FACTORS 2
USE OF PROCEEDS 3
DESCRIPTION OF CAPITAL STOCK 4
DESCRIPTION OF DEBT SECURITIES 7
DESCRIPTION OF WARRANTS 8
DESCRIPTION OF PURCHASE CONTRACTS 9
DESCRIPTION OF UNITS 10
PLAN OF DISTRIBUTION 11
WHERE YOU CAN FIND MORE INFORMATION 13
INFORMATION INCORPORATED BY REFERENCE 13
LEGAL MATTERS 14
EXPERTS 14

ABOUT THIS PROSPECTUS

This prospectus is part of an automatic shelf registration statement that we filed under the Securities Act of 1933, as amended (the “Securities Act”), with the Securities and Exchange Commission (the “SEC”) utilizing an automatic “shelf” registration process as a “well-known seasoned issuer” as defined in Rule 405 under the Securities Act.

Under this shelf registration process, we may issue and sell any combination of the securities described in this prospectus in one or more offerings from time to time. This prospectus provides you with a general description of the securities we may offer. Each time we offer the securities described in this prospectus, we will provide you with a prospectus supplement that will describe the specific amounts, prices and terms of the securities being offered. We may also authorize one or more free writing prospectuses to be provided to you that may contain material information relating to these offerings. The prospectus supplement or free writing prospectus may also add, update or change information contained in or incorporated by reference into this prospectus with respect to that offering. If there is any inconsistency between the information in this prospectus and the applicable prospectus supplement or free writing prospectus, you should rely on the prospectus supplement or free writing prospectus, as applicable. This prospectus does not contain all the information provided in the registration statement filed with the SEC. You should carefully read both this prospectus and any applicable prospectus supplement (and any applicable free writing prospectus) together with the additional information described below under “Where You Can Find More Information” and “Information Incorporated By Reference” before you make an investment decision.

We have not authorized anyone to provide any information other than that contained or incorporated by reference in this prospectus or in any prospectus supplement or free writing prospectus prepared by or on behalf of us or to which we have referred you. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you.

You should assume that the information appearing in this prospectus and the applicable prospectus supplement to this prospectus is accurate as of the date on its respective cover and that any information incorporated by reference is accurate only as of the date of the document incorporated by reference, unless we indicate otherwise. Our business, financial condition, results of operations and prospects may have changed since those dates. Any statement made in this prospectus or in a document incorporated or deemed to be incorporated by reference in this prospectus will be deemed to be modified or superseded for purposes of this prospectus to the extent that a statement contained in a prospectus supplement or in any other subsequently filed document that is also incorporated or deemed to be incorporated by reference in this prospectus modifies or supersedes that statement. Any statement so modified or superseded will not be deemed, except as so modified or superseded, to constitute a part of this prospectus. See “Information Incorporated By Reference.”

Unless the context otherwise indicates, references in this prospectus to the “Company,” “we,” “our” and “us” refer to MDU Resources Group, Inc. and its subsidiaries. The term “you” refers to a prospective investor.

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus, any related prospectus supplement and the documents that we incorporate by reference herein and therein may contain forward-looking statements within the meaning of Section 27A of the Securities Act, and Section 21E of the Securities Exchange Act of 1934, as amended (the “Exchange Act”). Other than statements of historical facts, all statements which address activities, events, or developments that the Company anticipates will or may occur in the future are based on underlying assumptions (many of which are based, in turn, upon further assumptions), including, but not limited to, statements identified by the words “anticipates,” “estimates,” “expects,” “intends,” “plans,” and “predicts” in each case related to such things as growth estimates, stockholder value creation, the Company’s “CORE” strategy, capital expenditures, financial guidance, trends, objectives, goals, dividend payout ratio targets, strategies and other such matters, are forward-looking statements. These forward-looking statements are based on many assumptions and factors, which are detailed in the Company’s filings with the SEC.

While made in good faith, these forward-looking statements are based largely on the Company’s expectations and judgments and are subject to a number of risks and uncertainties, many of which are unforeseeable and beyond the Company’s control. For additional discussion regarding risks and uncertainties that may affect forward-looking statements, see Part I, Item 1A. Risk Factors in the Company’s Annual Report on Form 10-K for the year ended December 31, 2024, Part II, Item 1A. Risk Factors in the Company’s Quarterly Reports on Form 10-Q for the quarters ended March 31, 2025 and June 30, 2025 and subsequent filings with the SEC. Any changes in such assumptions or factors could produce significantly different results. Undue reliance should not be placed on forward-looking statements, which speak only as of the date they are made. Except as required by applicable law, the Company undertakes no obligation to update the forward-looking statements, whether as a result of new information, future events, or otherwise.

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MDU RESOURCES GROUP, INC.

The Company is a pure-play regulated energy delivery business upon the completed separations of both its construction materials and contracting and construction services businesses. Montana-Dakota Utilities Co. (formerly known as MDU Resources Group, Inc., “Montana-Dakota”) was incorporated under the laws of the state of Delaware in 1924. The Company was incorporated under the laws of the state of Delaware in 2018. Upon the completion of an internal holding company reorganization, Montana-Dakota became a subsidiary of the Company. Our principal executive offices are located at 1200 West Century Avenue, P.O. Box 5650, Bismarck, North Dakota 58506-5650, telephone (701) 530-1000.

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RISK FACTORS

An investment in our securities involves risks. You should carefully consider the risks described in the sections entitled “Risk Factors” in any prospectus supplement and those set forth in documents incorporated by reference in this prospectus and any applicable prospectus supplement, including the risk factors set forth in our most recent Annual Report on Form 10-K and any subsequent Quarterly Reports on Form 10-Q or Current Reports on Form 8-K that we file after the date of this prospectus, as well as other information in this prospectus and any applicable prospectus supplement, before purchasing any of our securities. Each of the risks described in these sections and documents could materially and adversely affect our business, financial condition, results of operations and prospects, and could result in a loss of your investment. Additional risks and uncertainties not known to us or that we deem immaterial may also impair our business, financial condition, results of operations and prospects.

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USE OF PROCEEDS

Unless otherwise indicated in the applicable prospectus supplement, we intend to use the net proceeds from the sale of any securities offered by us under this prospectus for general corporate purposes, which may include repayment or refinancing of debt, acquisitions, working capital, capital expenditures, and repurchases or redemptions of securities. We will retain broad discretion over the allocation of net proceeds from the sale of any securities offered by us.

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DESCRIPTION OF CAPITAL STOCK

General

The following description of our capital stock is intended as a summary only. This description is based upon, and is qualified by reference to, our Amended and Restated Certificate of Incorporation, as amended to date (our “certificate of incorporation”), our Bylaws, as amended and restated to date (our “bylaws”), and applicable provisions of the General Corporation Law of the State of Delaware (the “DGCL”). This summary is not complete. You should read our certificate of incorporation and our bylaws, which are incorporated by reference as exhibits to the registration statement of which this prospectus forms a part, for the provisions that are important to you.

Authorized and Outstanding Capital Stock

Our certificate of incorporation authorizes us to issue 502,000,000 shares of stock, divided into two classes:

500,000,000 shares of common stock, $1.00 par value per share; and
2,000,000 shares of preferred stock, $100 par value per share.

As of July 31, 2025, we had 204,331,170 shares of common stock and no shares of preferred stock issued and outstanding.

Common Stock

Dividend Rights

Subject to preferences that may be applicable to any then outstanding preferred stock, holders of our common stock are entitled to receive dividends, if any, as may be declared from time to time by our Board of Directors (the “Board”) out of legally available funds.

Voting Rights

Our common stock has one vote per share. The holders of our common stock are entitled to vote on all matters to be voted on by stockholders. The holders of our common stock do not have cumulative voting rights.

Our bylaws provide for a majority voting standard for the election of directors in an uncontested election and a plurality voting standard in the event the number of nominees exceeds the number of directors to be elected.

Liquidation Rights

Upon our liquidation, dissolution or winding up and after payment in full of all amounts required to be paid to creditors and to the holders of preferred stock having liquidation preferences, if any, the holders of our common stock will be entitled to receive pro rata our remaining assets available for distribution.

Other Rights

Holders of our common stock do not have preemptive, subscription, redemption or conversion rights. Our common stock is not liable to further calls or assessment. There are no redemption or sinking fund provisions applicable to the common stock. All shares of our common stock that are outstanding are fully paid and non-assessable. The rights, powers, preferences and privileges of holders of our common stock are subject to and may be adversely affected by the rights of the holders of any shares of our preferred stock we may authorize and issue in the future.

Preferred Stock

Our certificate of incorporation authorizes our Board to issue up to 2,000,000 shares of preferred stock, from time to time in one or more classes or series, generally without any vote or action by the holders of our common stock. Our Board will be authorized to determine the number of shares and designation of any class or series of preferred stock and the powers, rights, preferences and privileges of each class or series of preferred stock, including, the dividend rate, dividend rights, conversion rights and terms, voting rights, redemption rights and terms, liquidation preferences and sinking fund terms of any class or series of preferred stock, which may be greater than the rights of the holders of the common stock. There are no shares of preferred stock outstanding.

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The purpose of authorizing our Board to issue preferred stock and determine its rights and preferences is to eliminate delays associated with a shareholder vote on specific issuances. The issuance of preferred stock, while providing flexibility in connection with possible acquisitions, future financings and other corporate purposes, could have the effect of making it more difficult for a third party to acquire, or could discourage a third party from seeking to acquire, a majority of our outstanding voting stock. Additionally, the issuance of preferred stock may adversely affect the holders of our common stock by restricting dividends on our common stock, diluting the voting power of our common stock or subordinating the liquidation rights of our common stock. As a result of these or other factors, the issuance of preferred stock could have an adverse impact on the market price of our common stock

Provisions of our Certificate of Incorporation and our Bylaws and Certain Provisions of Delaware Law That Could Delay or Prevent a Change in Control

Our certificate of incorporation, bylaws and the DGCL, which are summarized in the following paragraphs, contain provisions that are intended to enhance the likelihood of continuity and stability in the composition of our Board. These provisions are intended to avoid costly takeover battles, reduce our vulnerability to a hostile change of control and enhance the ability of our Board to maximize shareholder value in connection with any unsolicited offer to acquire us. However, these provisions may have an anti-takeover effect and may delay, deter or prevent a merger or acquisition of our company by means of a tender offer, a proxy contest or other takeover attempt that a shareholder might consider in its best interest, including those attempts that might result in a premium over the prevailing market price for the shares of common stock held by shareholders.

Authorized but Unissued Capital Stock

The authorized but unissued shares of common stock and preferred stock are available for future issuance without shareholder approval, subject to any limitations imposed by the listing rules of the NYSE. These additional shares may be used for a variety of corporate finance transactions, acquisitions and employee benefit plans. The existence of authorized but unissued and unreserved common stock and preferred stock could make more difficult or discourage an attempt to obtain control of us by means of a proxy contest, tender offer, merger or otherwise.

Number of Directors, Vacancies, Removal of Directors

Our certificate of incorporation provides that our Board will have at least six and at most 15 directors. A majority of the Board decides the exact number of directors at a given time. A majority of the directors then in office fill any new directorships created by the Board and any vacancies.

Under the laws of the state of Delaware, our directors may be removed by a majority of the shares then entitled to vote in an election of directors. However, our certificate of incorporation provides that any action required or permitted to be taken by our stockholders, which includes the removal of directors, must be effected at a duly called annual or special meeting of stockholders and may not be effected by any consent in writing by such stockholders. Our certificate of incorporation prevents stockholders from calling a special meeting.

No Cumulative Voting

Under Delaware law, the right to vote cumulatively does not exist unless the certificate of incorporation specifically authorizes cumulative voting. Our certificate of incorporation does not provide for cumulative voting. Accordingly, a holder or group of holders of a majority of the shares of our common stock are able to elect all of the directors.

Requirements for Advance Notification of Shareholder Meetings, Director Nominations and Shareholder Proposals

Our bylaws require that for a stockholder to nominate a director or bring other business before an annual meeting, the stockholder must give notice not earlier than the close of business on the 120th day prior to the first anniversary of the preceding year’s annual meeting of stockholders and not later than the close of business on the 90th day prior to the first anniversary of the prior year’s annual meeting of stockholders. In order for any matter to be “properly brought” before an annual meeting, a stockholder will have to comply with these advance notice requirements and provide us with certain information. Stockholders at an annual meeting may only consider proposals or nominations specified in the notice of meeting or brought before the meeting by or at the direction of our Board or by a qualified stockholder of record on the record date for the meeting, who is entitled to vote at the meeting and who has delivered timely written notice in proper form to our secretary of the stockholder’s intention to bring such business before the meeting. These provisions could have the effect of delaying stockholder actions that are favored by the holders of a majority of our outstanding voting securities until the next stockholder meeting.

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In addition, our bylaws also provide for proxy access, pursuant to which a qualifying stockholder, or a group of up to 20 such stockholders, owning at least 3% of our outstanding common stock continuously for at least three years, will generally be able to nominate and include in our proxy materials for an annual meeting of stockholders, qualifying director nominees constituting up to the greater of two nominees or 20% of the total number of directors of the Company; provided that the qualifying stockholder(s) and director nominee(s) satisfy the eligibility, procedural and other requirements specified in our bylaws, including that notice of a nomination be delivered to our secretary not less than 120 days or more than 150 days before the first anniversary of the date that we first sent our proxy statement to stockholders for the prior year’s annual meeting.

Stockholder Action by Written Consent; Special Meeting of Stockholders

Our certificate of incorporation eliminates the ability of stockholders to act by written consent. Our bylaws provide that special meetings of our stockholders may be called only by the Board.

Provisions of Delaware Law That Could Delay or Prevent a Change in Control

We are subject to the provisions of Section 203 of the DGCL. With some exceptions, this law prohibits us from engaging in some types of business combinations with a person who owns 15% or more of our outstanding voting stock for a three-year period after that person acquires the stock. This prohibition does not apply if:

our Board approved the business combination or the transaction of our stock before the person became an interested stockholder;
upon consummation of the transaction that resulted in the person becoming an interested stockholder, that person owned at least 85% of our outstanding voting stock outstanding at the time of the transaction, excluding certain shares; or
at or subsequent to such time the business combination is approved by the Board and by at least two-thirds of the outstanding voting stock not owned by the interested stockholder.

A “business combination” includes, among other things, a merger or consolidation involving us and the “interested stockholder” and the sale of more than 10% of our assets. In general, an “interested stockholder” is any entity or person beneficially owning 15% or more of our outstanding voting stock and any entity or person affiliated with or controlling or controlled by such entity or person.

Forum Selection

Our bylaws provide that, unless we consent in writing to the selection of an alternative forum, the Court of Chancery of the State of Delaware shall be the sole and exclusive forum for any Internal Corporate Claims. As defined in our bylaws, “Internal Corporate Claims” means claims, including claims in the right of the Company, (i) that are based upon a violation of a duty by a current or former director or officer or stockholder in such capacity, or (ii) as to which the DGCL confers jurisdiction upon the Court of Chancery of the State of Delaware. Although we have included a choice of forum clause in our bylaws, it is possible that a court could rule that such clause is inapplicable or unenforceable.

Transfer Agent; Registrar

The transfer agent and registrar for our common stock is EQ Shareowner Services.

Listing

Our common stock is listed on the NYSE and trades under the symbol “MDU.”

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DESCRIPTION OF DEBT SECURITIES

We may issue debt securities from time to time under this prospectus. We will set forth in an accompanying prospectus supplement a description of the debt securities that may be offered under this prospectus. The debt securities will be issued under one or more indentures, which may include existing indentures. The applicable prospectus supplement and other offering material relating to such offering will describe the specific terms relating to the series of debt securities being offered, including a description of the material terms of the indenture (and any supplemental indentures) governing such series. These terms may include the following:

the title of the series of the offered debt securities;
the price or prices at which the offered debt securities will be issued;
any limit on the aggregate principal amount of the offered debt securities;
the date or dates on which the principal of the offered debt securities will be payable;
the rate or rates (which may be fixed or variable) per year at which the offered debt securities will bear interest, if any, or the method of determining the rate or rates and the date or dates from which interest, if any, will accrue;
if the amount of principal, premium or interest with respect to the offered debt securities of the series may be determined with reference to an index or pursuant to a formula, the manner in which these amounts will be determined;
the date or dates on which interest, if any, on the offered debt securities will be payable and the regular record dates for the payment thereof;
the place or places, if any, in addition to or instead of the corporate trust office of the trustee, where the principal, premium and interest with respect to the offered debt securities will be payable;
the period or periods, if any, within which, the price or prices of which, and the terms and conditions upon which the offered debt securities may be redeemed, in whole or in part, pursuant to optional redemption provisions;
the terms on which we would be required to redeem or purchase the offered debt securities pursuant to any sinking fund or similar provision, and the period or periods within which, the price or prices at which and the terms and conditions on which the offered debt securities will be so redeemed and purchased in whole or in part;
the denominations in which the offered debt securities will be issued;
the form of the offered debt securities and whether the offered debt securities are to be issued in whole or in part in the form of one or more global securities and, if so, the identity of the depositary for the global security or securities;
the portion of the principal amount of the offered debt securities that is payable on the declaration of acceleration of the maturity, if other than their principal amount;
if other than U.S. dollars, the currency or currencies in which the offered debt securities will be denominated and payable, and the holders’ rights, if any, to elect payment in a foreign currency or a foreign currency unit other than that in which the offered debt securities are otherwise payable;
whether the offered debt securities will be issued with guarantees and, if so, the terms of any guarantee of the payment of principal and interest with respect to the offered debt securities;
any addition to, or modification or deletion of, any event of default or any covenant specified in the indenture;
whether the offered debt securities will be convertible or exchangeable into other securities, and if so, the terms and conditions upon which the offered debt securities will be convertible or exchangeable;
whether the offered debt securities will be senior or subordinated debt securities;
any trustees, authenticating or paying agents, transfer agents or registrars or other agents with respect to the offered debt securities; and
any other specific terms of the offered debt securities.

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DESCRIPTION OF WARRANTS

We may issue warrants for the purchase of debt securities, common stock, preferred stock or other securities. Warrants may be issued independently or together with debt securities, common stock, preferred stock or other securities offered by any prospectus supplement and may be attached to or separate from any such offered securities. Each series of warrants will be issued under a separate warrant agreement to be entered into between us and a bank or trust company, as warrant agent, all as will be set forth in the prospectus supplement relating to the particular issue of warrants. The warrant agent will act solely as our agent in connection with the warrants and will not assume any obligation or relationship of agency or trust for or with any holders of warrants or beneficial owners of warrants. The summary of the terms of the warrants contained in this prospectus is not complete and is subject to, and is qualified in its entirety to, all provisions of the applicable warrant agreement.

Reference is made to the prospectus supplement relating to the particular issue of warrants offered pursuant to such prospectus supplement for the terms of and information relating to such warrants, which may include:

the specific designation and aggregate number of, and the offering price at which we will issue, the warrants;
the currency or currency units in which the offering price, if any, and the exercise price are payable; 
the date on which the right to exercise the warrants will begin and the date on which that right will expire or, if the holder may not continuously exercise the warrants throughout that period, the specific date or dates on which the holder may exercise the warrants; 
whether the warrants are to be sold separately or with other securities as parts of units; 
whether the warrants will be issued in definitive or global form or in any combination of these forms, although, in any case, the form of a warrant included in a unit will correspond to the form of the unit and of any security included in that unit; 
any applicable material U.S. federal income tax consequences; 
the identity of the warrant agent for the warrants and of any other depositaries, execution or paying agents, transfer agents, registrars or other agents; 
the proposed listing, if any, of the warrants or any securities purchasable upon exercise of the warrants on any securities exchange; 
the designation and terms of any equity securities purchasable upon exercise of the warrants; 
the designation, aggregate principal amount, currency and terms of any debt securities that may be purchased upon exercise of the warrants; 
if applicable, the designation and terms of the debt securities, preferred stock, depositary shares or common stock with which the warrants are issued and the number of warrants issued with each security; 
if applicable, the date from and after which any warrants issued as part of a unit and the related debt securities, preferred stock or common stock will be separately transferable; 
the number of shares of preferred stock, the number of shares of common stock purchasable upon exercise of a warrant and the price at which those shares may be purchased;
if applicable, the minimum or maximum amount of the warrants that may be exercised at any one time; 
information with respect to book-entry procedures, if any; 
the antidilution provisions of, and other provisions for changes to or adjustment in the exercise price of, the warrants, if any; 
any redemption or call provisions; and 
any additional terms of the warrants, including terms, procedures and limitations relating to the exchange or exercise of the warrants.

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DESCRIPTION OF PURCHASE CONTRACTS

We may issue, from time to time, purchase contracts, including contracts obligating holders to purchase from us and us to sell to the holders, a specified principal amount of debt securities, shares of common stock or preferred stock, or any of the other securities that we may sell under this prospectus at a future date or dates. The consideration payable upon settlement of the purchase contracts may be fixed at the time the purchase contracts are issued or may be determined by a specific reference to a formula set forth in the purchase contracts. The purchase contracts may be issued separately or as part of units consisting of a purchase contract and other securities or obligations issued by us or third parties, including United States treasury securities, securing the holders' obligations to purchase the relevant securities under the purchase contracts. The purchase contracts may require us to make periodic payments to the holders of the purchase contracts or units or vice versa, and the payments may be unsecured or prefunded on some basis. The purchase contracts may require holders to secure their obligations under the purchase contracts. The summary of the terms of the purchase contracts contained in this prospectus is not complete and is subject to, and is qualified in its entirety by, all provisions of the applicable purchase contracts.

The prospectus supplement related to any particular purchase contracts will describe, among other things, the material terms of the purchase contracts and of the securities being sold pursuant to such purchase contracts, a discussion, if appropriate, of any special U.S. federal income tax considerations applicable to the purchase contracts and any material provisions governing the purchase contracts that differ from those described above. The description in the prospectus supplement will not necessarily be complete and will be qualified in its entirety by reference to the purchase contracts, and, if applicable, collateral arrangements and depositary arrangements, relating to the purchase contracts.

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DESCRIPTION OF UNITS

We may, from time to time, issue units comprised of one or more of the other securities that may be offered under this prospectus, in any combination. Each unit may also include debt obligations of third parties, such as U.S. Treasury securities. Each unit will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security. The unit agreement under which a unit is issued may provide that the securities included in the unit may not be held or transferred separately at any time, or at any time before a specified date or other specific circumstances occur. The summary of the terms of the units contained in this prospectus is not complete and is subject to, and is qualified in its entirety by, all provisions of the applicable unit agreements.

Any prospectus supplement related to any particular units will describe, among other things:

the material terms of the units and of the securities comprising the units, including whether and under what circumstances those securities may be held or transferred separately; 
any material provisions relating to the issuance, payment, settlement, transfer or exchange of the units or of the securities comprising the units; 
if appropriate, any special U.S. federal income tax considerations applicable to the units; and 
any material provisions of the governing unit agreement that differ from those described above.

The applicable provisions described in this section, as well as those described under “Description of Capital Stock,” “Description of Debt Securities,” “Description of Warrants” and “Description of Purchase Contracts,” will apply to each unit and to each security included in each unit, respectively.

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PLAN OF DISTRIBUTION

We may sell the securities being offered hereby:

directly to purchasers;
through agents;
through dealers;
through underwriters;
through a combination of any of the above methods of sale; or
through any other methods described in a prospectus supplement.

We will identify the specific plan of distribution, including any direct purchasers, agents, dealers, underwriters and, if applicable, their compensation, the purchase price, the net proceeds to us, the public offering price, and any discounts or concessions allowed or reallowed or paid to dealers, in a prospectus supplement.

The distribution of securities may be effected, from time to time, in one or more transactions, including block transactions and transactions on the NYSE or any other organized market where the securities may be traded. The securities may be sold at a fixed price or prices, which may be changed, or at market prices prevailing at the time of sale, at prices relating to the prevailing market prices or at negotiated prices. The consideration may be cash or another form negotiated by the parties. Agents, underwriters or broker-dealers may be paid compensation for offering and selling the securities. That compensation may be in the form of discounts, concessions or commissions to be received from us or from the purchasers of the securities.

We may also make sales of our common stock in transactions that are deemed to be “at the market offerings,” as defined in Rule 415(a)(4) under the Securities Act, including sales made by means of ordinary brokers’ transactions on the NYSE at market prices, or otherwise as agreed between us and one or more underwriters, dealers or agents. If we engage in such transactions, we will do so pursuant to the terms of a distribution agreement between us and the underwriters, dealers or agents. If we engage in at-the-market sales pursuant to a distribution agreement, we will issue and sell shares of our common stock to or through one or more underwriters, dealers or agents, which may act on an agency basis or on a principal basis. During the term of any such distribution agreement, we may sell shares on a daily basis in exchange transactions or otherwise as we agree with the underwriters, dealers or agent. The distribution agreement may provide that any shares of our common stock sold will be sold at prices related to the then prevailing market prices for our securities. Pursuant to the terms of the distribution agreement, we also may agree to sell, and the relevant underwriters, dealers or agents may agree to solicit offers to purchase, blocks of our common stock. The terms of each such distribution agreement will be set forth in more detail in a prospectus supplement to this prospectus. To the extent that any named underwriter, dealer or agent acts as principal pursuant to the terms of a distribution agreement, or if we offer to sell shares of our common stock through another dealer acting as underwriter, then such named underwriter may engage in certain transactions that stabilize, maintain or otherwise affect the price of our common stock. We will describe any such activities in the prospectus supplement relating to the transaction. To the extent that any named dealer or agent acts as agent on a best efforts basis pursuant to the terms of a distribution agreement, such dealer or agent will not engage in any such stabilization transactions.

Offers to purchase the securities may be solicited directly by us or by agents designated by us from time to time. We will, in the prospectus supplement relating to an offering, name any agent that could be viewed as an underwriter under the Securities Act and describe any commissions we must pay. Any such agent will be acting on a best efforts basis for the period of its appointment or, if indicated in the applicable prospectus supplement, on a firm commitment basis.

If a dealer is utilized in the sale of the securities in respect of which this prospectus is delivered, we will sell the securities to the dealer, as principal. The dealer, which may be deemed to be an underwriter as that term is defined in the Securities Act, may then resell the securities to the public at varying prices to be determined by the dealer at the time of resale. Dealer trading may take place in certain of the securities, including securities not listed on any securities exchange.

If an underwriter or underwriters are utilized in the sale, we will execute an underwriting or similar agreement with the underwriters at the time of sale to them and the names of the underwriters will be set forth in the applicable prospectus supplement, which will be used by the underwriters to make resales of the securities in respect of which this prospectus is delivered to the public. The obligations of underwriters to purchase securities will be subject to certain conditions precedent and the underwriters will be obligated to purchase all of the securities of a series if any are purchased.

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We may directly solicit offers to purchase the securities and we may make sales of securities directly to institutional investors or others. These persons may be deemed to be underwriters within the meaning of the Securities Act with respect to any resale of the securities. To the extent required, the prospectus supplement will describe the terms of any such sales, including the terms of any bidding or auction process, if used.

Underwriters, dealers, agents and other persons may be entitled, under agreements that may be entered into with us, to indemnification against certain civil liabilities, including liabilities under the Securities Act, or to contribution with respect to payments that they may be required to make in respect thereof. Underwriters, dealers and agents may engage in transactions with, or perform services for, us in the ordinary course of business.

Any person participating in the distribution of common stock registered under the registration statement that includes this prospectus will be subject to applicable provisions of the Exchange Act, and the applicable SEC rules and regulations, including, among others, Regulation M, which may limit the timing of purchases and sales of our common stock by any such person. Furthermore, Regulation M may restrict the ability of any person engaged in the distribution of our common stock to engage in market-making activities with respect to our common stock. These restrictions may affect the marketability of our common stock and the ability of any person or entity to engage in market-making activities with respect to our common stock.

Except as described above, in order to facilitate the offering of the securities, any underwriters may engage in transactions that stabilize, maintain or otherwise affect the price of the securities or any other securities the prices of which may be used to determine payments on such securities. Specifically, any underwriters may overallot in connection with the offering, creating a short position for their own accounts. In addition, to cover overallotments or to stabilize the price of the securities or of any such other securities, the underwriters may bid for, and purchase, the securities or any such other securities in the open market. Finally, in any offering of the securities through a syndicate of underwriters, the underwriting syndicate may reclaim selling concessions allowed to an underwriter or a dealer for distributing the securities in the offering if the syndicate repurchases previously distributed securities in transactions to cover syndicate short positions, in stabilization transactions or otherwise. Any of these activities may stabilize or maintain the market price of the securities above independent market levels. Any such underwriters are not required to engage in these activities and may end any of these activities at any time.

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WHERE YOU CAN FIND MORE INFORMATION

        

We file annual, quarterly and current reports, proxy statements and other information with the SEC. Our SEC filings are available over the Internet at the SEC’s web site at www.sec.gov. Our filings with the SEC are also available free of charge on our website at www.mdu.com. The information on our website (or any other website referred to in this prospectus or any applicable prospectus supplement) is not incorporated by reference in this prospectus or any prospectus supplement and you should not consider it a part of this prospectus or any accompanying prospectus supplement.

INFORMATION INCORPORATED BY REFERENCE

The SEC allows us to “incorporate by reference” the information we file with them, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this prospectus and any accompanying prospectus supplement, and later information filed with the SEC will automatically update and supersede this information. We incorporate by reference the documents listed below and all documents subsequently filed with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, prior to the termination of the offering under this prospectus and any prospectus supplement (other than information deemed furnished and not filed in accordance with SEC rules, including Items 2.02 and 7.01 of Form 8-K):

our Annual Report on Form 10-K for the year ended December 31, 2024, filed with the SEC on February 20, 2025;

the Part III information contained in our definitive proxy statement on Schedule 14A for our 2025 annual meeting of stockholders, filed with the SEC on April 3, 2025, that was incorporated into our Annual Report on Form 10-K for the year ended December 31, 2024, filed with the SEC on February 20, 2025;

our Quarterly Reports on Form 10-Q for the quarters ended March 31, 2025 and June 30, 2025, filed with the SEC on May 8, 2025 and August 7, 2025, respectively;

our Current Reports on Form 8-K filed with the SEC on February 14, 2025 and May 15, 2025; and

the description of our securities contained in Exhibit 99(b) to our Current Report on Form 8-K12B, filed with the SEC on January 2, 2019, including any amendments or reports filed for the purpose of updating such description (including Exhibit 4(a) to our Annual Report on Form 10-K for the year ended December 31, 2019, filed with the SEC on February 21, 2020).

We will provide to each person, including any beneficial owner, to whom a copy of this prospectus is delivered, a copy of any or all of the information that has been incorporated by reference in this prospectus but not delivered with this prospectus. We will provide this information upon written or oral request at no cost to the requester. You should direct your requests to:

Office of the Treasurer

MDU Resources Group, Inc.

1200 West Century Avenue

P.O. Box 5650

Bismarck, North Dakota 58506-5650

Telephone: (701) 530-1000

13

LEGAL MATTERS

Unless the applicable prospectus supplement indicates otherwise, the validity of the securities offered by this prospectus will be passed upon for us by Perkins Coie LLP.

EXPERTS

The financial statements of MDU Resources Group, Inc. incorporated by reference in this Prospectus, and the effectiveness of MDU Resources Group, Inc.’s internal control over financial reporting have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their reports. Such financial statements are incorporated by reference in reliance upon the reports of such firm, given their authority as experts in accounting and auditing.

14

PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14.Other Expenses of Issuance and Distribution.

The following table sets forth the expenses payable by us in connection with the issuance and distribution of the securities covered by this Registration Statement, other than underwriting discounts and commissions.  All expenses are estimates.

Securities and Exchange Commission registration fee $     *
Financial Industry Regulatory Authority filing fee **
New York Stock Exchange supplemental listing fee **
Printing expenses **
Accounting fees and expenses **
Legal fees and expenses **
Transfer agent and registrar fees and expenses **
Trustee fees and expenses **
Rating agency fees **
Depositary fees and expenses **
Warrant agent fees and expenses **
Miscellaneous

**

         Total

$   **

*Pursuant to Rules 456(b) and 457(r) under the Securities Act of 1933, as amended, the Securities and Exchange Commission (the “SEC”) registration fee will be paid at the time of any particular offering of securities under the registration statement, and is therefore not currently determinable.

**These expenses are calculated in part based on the number of issuances and the amount of securities offered and accordingly cannot be estimated at this time.

Item 15.Indemnification of Directors and Officers.

Subsection (a) of Section 145 of the DGCL empowers a corporation to indemnify any person who was or is a party or who is threatened to be made a party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative (other than an action by or in the right of the corporation) by reason of the fact that the person is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise, against expenses (including attorneys’ fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by the person in connection with such action, suit or proceeding if the person acted in good faith and in a manner the person reasonably believed to be in or not opposed to the best interests of the corporation, and, with respect to any criminal action or proceeding, had no reasonable cause to believe the person’s conduct was unlawful.

Subsection (b) of Section 145 empowers a corporation to indemnify any person who was or is a party or is threatened to be made a party to any threatened, pending or completed action or suit by or in the right of the corporation to procure a judgment in its favor by reason of the fact that the person acted in any of the capacities set forth above, against expenses (including attorneys’ fees) actually and reasonably incurred by the person in connection with the defense or settlement of such action or suit if the person acted in good faith and in a manner the person reasonably believed to be in or not opposed to the best interests of the corporation, except that no indemnification shall be made in respect of any claim, issue or matter as to which such person shall have been adjudged to be liable to the corporation unless and only to the extent that the Court of Chancery or the court in which such action or suit was brought shall determine upon application that, despite the adjudication of liability but in view of all the circumstances of the case, such person is fairly and reasonably entitled to indemnity for such expenses which the Court of Chancery or such other court shall deem proper.

Section 145 further provides that to the extent a director or officer of a corporation has been successful on the merits or otherwise in the defense of any action, suit or proceeding referred to in subsections (a) and (b) of Section 145, or in defense of any claim, issue or matter therein, such person shall be indemnified against expenses (including attorneys’ fees) actually and reasonably incurred by such person in connection therewith; that indemnification provided for by Section 145 shall not be deemed exclusive of any other rights to which the indemnified party may be entitled; and the indemnification provided for by Section 145 shall, unless otherwise provided when authorized or ratified, continue as to a person who has ceased to be a director, officer, employee or agent and shall inure to the benefit of such person’s heirs, executors and administrators.

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Section 145 also empowers the corporation to purchase and maintain insurance on behalf of any person who is or was a director, officer, employee or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise against any liability asserted against such person and incurred by such person in any such capacity, or arising out of his status as such, whether or not the corporation would have the power to indemnify such person against such liability under Section 145.

Section 102(b)(7) of the DGCL provides that a corporation’s certificate of incorporation may contain a provision eliminating or limiting the personal liability of a director to the corporation or its stockholders for monetary damages for breach of fiduciary duty as a director, provided that such provision shall not eliminate or limit the liability of: (i) a director or officer for any breach of the director’s or officer’s duty of loyalty to the corporation or its stockholders, (ii) a director or officer for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (iii) a director under Section 174 of the DGCL, (iv) a director or officer for any transaction from which the director or officer derived an improper personal benefit; or (v) an officer any action by or in the right of the corporation. The registrant’s amended and restated certificate of incorporation (the “certificate of incorporation”) contains such a provision.

The registrant’s bylaws (as amended and restated to date, the “bylaws”) provide that the registrant shall indemnify and hold harmless, to the fullest extent permitted by applicable law, any director or former director or officer or former officer of the registrant (a “Director or Officer”) who was or is made or is threatened to be made a party or is otherwise involved in any action, suit or proceeding, whether civil, criminal, administrative or investigative (a “Proceeding”) by reason of the fact that he or she is or was a director of officer of the registrant or is or was serving at the request of the registrant as a director, officer, employee or agent of another corporation or of a partnership, limited liability company, joint venture, trust, non-profit entity or other enterprise, including service with respect to employee benefit plans, against all expenses, liability and loss (including attorneys’ fees, judgments, fines, penalties, excise taxes and penalties assessed with respect to employee benefit plans, and amounts paid in settlement) actually and reasonably incurred by such Director or Officer. Notwithstanding the preceding sentence, the registrant is required to indemnify and hold harmless a Director or Officer in connection with a Proceeding (or part thereof) initiated by such Director or Officer only if the Proceeding (or part thereof) was authorized by the registrant’s board of directors. The bylaws also provide that the registrant will pay the expenses (including attorneys’ fees) actually and reasonably incurred by a Director or Officer in defending any Proceeding in advance of its final disposition, subject to the terms and conditions set forth therein. In addition, the bylaws provide that the registrant may provide indemnification and advancement of expenses (including attorneys’ fees) to employees and agents to the extent permitted by applicable law.

The registrant has also obtained liability insurance covering its directors and officers for claims asserted against them or incurred by them in such capacity.

In addition, the registrant has entered into agreements to indemnify its directors and certain of its officers in addition to the indemnification provided for in the certificate of incorporation and the bylaws. These agreements, among other things, indemnify the registrant’s directors and some of our officers for certain expenses (including attorney’s fees), judgments, fines and settlement amounts incurred by such person in any action or proceeding, including any action by or in our right, on account of services by that person as a director or officer of the registrant or as a director or officer of any of its subsidiaries, or as a director or officer of any other company or enterprise that the person provides services to at the registrant’s request.

Any underwriting agreement or distribution agreement that the registrant enters into with any underwriters or agents involved in the offering or sale of any securities registered hereby may require such underwriters or dealers to indemnify the registrant, some or all of its directors and officers and its controlling persons, if any, for specified liabilities, which may include liabilities under the Securities Act of 1933, as amended.

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Item 16. Exhibits.

Exhibit No.

Description

+1 Form of Underwriting Agreement.
4(a) Amended and Restated Certificate of Incorporation of MDU Resources Group, Inc. (incorporated herein by reference to Exhibit 3.2 to MDU Resources Group, Inc.’s Current Report on Form 8-K, filed on May 8, 2019 (File No. 001-03480)).
4(b) Bylaws of MDU Resources Group, Inc. (incorporated herein by reference to Exhibit 3.1 to MDU Resources Group, Inc.’s Current Report on Form 8-K, filed on February 14, 2025 (File No. 001-03480)).
+4(c) Form of Indenture.
+4(d) Form of Note.
+4(e) Form of Certificate of Designation.
+4(f) Specimen of Preferred Stock Certificate.
+4(g) Form of Warrant Agreement.
+4(h) Form of Purchase Contract.
+4(i) Form of Unit Agreement.
*5(a) Opinion of Perkins Coie LLP.
*23(a) Consent of Deloitte & Touche LLP.
*23(b) Consent of Perkins Coie LLP (included in Exhibit 5(a)).
*24 Power of Attorney (included on the signature pages hereof).
25(a)# Form T-l Statement of Eligibility under the Trust Indenture Act of 1939, as amended, with respect to the Indenture filed as Exhibit 4(c).
*107 Filing Fee Table.

*Filed herewith.
+  To be filed by amendment, as an exhibit to a Current Report on Form 8-K or by other applicable filing with the SEC to be incorporated by reference herein.
#To be filed in accordance with the requirements of Section 305(b)(2) of the Trust Indenture Act of 1939, as amended.

Item 17.Undertakings

(a) The undersigned registrant hereby undertakes:

(1)                             To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

(i) to include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

(ii) to reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than 20% change in the maximum aggregate offering price set forth in the “Calculation of Filing Fee Tables” or “Calculation of Registration Fee” table, as applicable, in the effective registration statement; and

(iii) to include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;

provided, however, that paragraphs (a)(1)(i), (a)(1)(ii) and (a)(1)(iii) above do not apply if the registration statement is on Form S-3 and the information required to be included in a post-effective amendment by

 II-3 

 

those paragraphs is contained in reports filed with or furnished to the Commission by the registrant pursuant to section 13 or section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the registration statement.

(2)       That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(3)       To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(4)        That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser:

(A) Each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and

(B) Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii), or (x) for the purpose of providing the information required by section 10(a) of the Securities Act of 1933 shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date.

(5)        That, for the purpose of determining liability of the registrant under the Securities Act of 1933 to any purchaser in the initial distribution of the securities, the undersigned registrant undertakes that in a primary offering of securities of the undersigned registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

(i) Any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424;

(ii) Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by the undersigned registrant;

(iii) The portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and

(iv) Any other communication that is an offer in the offering made by the undersigned registrant to the purchaser.

(b) The undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant’s annual report pursuant to section 13(a) or section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be

 II-4 

 

deemed to be the initial bona fide offering thereof.

(c) Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Act and will be governed by the final adjudication of such issue.

 II-5 

 

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Bismarck, State of North Dakota on the 7th day of August, 2025.

MDU RESOURCES GROUP, INC.
By:      /s/ Nicole A. Kivisto
Nicole A. Kivisto
President and Chief Executive Officer

POWER OF ATTORNEY

Each person whose signature appears below constitutes and appoints Nicole A. Kivisto, Jason L. Vollmer and Anthony D. Foti, and each or either of them, his or her true and lawful attorney-in-fact and agent, each acting alone, with full power of substitution and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities, to sign any or all amendments or supplements (including post-effective amendments) to this registration statement on Form S-3, and to file the same, with all exhibits thereto, and all documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorney-in-fact and agent, full power and authority to do and perform each and every act and thing requisite and necessary to be done in and about the premises, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorney-in-fact and agent, or his or her substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed by the following persons in the capacities and on the dates indicated.

Signature

Title

Date

/s/ Nicole A. Kivisto

Nicole A. Kivisto

President, Chief Executive Officer and Director August 7, 2025

/s/ Jason L. Vollmer

Jason L. Vollmer

Chief Financial Officer August 7, 2025

/s/ Stephanie A. Sievert

Stephanie A. Sievert

Chief Accounting and Regulatory Affairs Officer August 7, 2025

/s/ Darrel T. Anderson

Darrel T. Anderson

Chair of the Board August 7, 2025

/s/ Vernon A. Dosch

Vernon A. Dosch

Director August 7, 2025

/s/ Marian M. Durkin

Marian M. Durkin

Director August 7, 2025

/s/ Douglas W. Jaeger

Douglas W. Jaeger

Director August 7, 2025

/s/ Dennis W. Johnson

Director August 7, 2025
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Dennis W. Johnson

/s/ Priti R. Patel

Priti R. Patel

Director August 7, 2025

 II-7 

FAQ

How many Corebridge (CRBG) shares are being sold in this offering?

AIG is selling 30 million shares, with an option for the underwriter to buy an additional 4.5 million.

Does Corebridge receive any proceeds from the sale?

No. All ~$1.01 billion in gross proceeds go to AIG, the selling shareholder.

Will existing shareholders be diluted?

No dilution; the shares are already outstanding and are transferred from AIG to public investors.

What will AIG’s ownership be after the transaction?

Approximately 15.58 % (or 14.74 % if the 4.5 millionâ€share option is fully exercised).

What is Corebridge’s current dividend policy?

The company pays a $0.24 quarterly cash dividend; the next payment is scheduled for 30 Sep 2025.

How much capacity remains under the share-repurchase program?

About $3.9 billion is still authorized following recent buy-backs.
Mdu Resources

NYSE:MDU

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3.62B
202.30M
0.94%
83.77%
3.09%
Conglomerates
Mining & Quarrying of Nonmetallic Minerals (no Fuels)
United States
BISMARCK