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AMEREN CORP 8-K Report, Executive Changes (Oct 3, 2025)

Reports
Leadership Changes
Filing Date
Filed October 3, 2025
Period End
October 2, 2025
Security
AEE
In the record · 2016–202610-K1110-Q328-K155

AEE filed 11 annual reports (10-K), 32 quarterly reports (10-Q) and 155 current reports (8-K) between 2016 and 2026.

  1. Material agreement8-K · Dec ’18Dec ’18
  2. Leadership change8-K · Dec ’20Dec ’20
  3. Material agreement8-K · Dec ’22Dec ’22
  4. Leadership change8-K · Dec ’24Dec ’24

01—Abstract

Summary

Summary of the 8-K filed October 3, 2025. Cited figures are marked; the original filing is the authoritative source.

Ameren Corporation (AEE) announced a significant leadership change in its key subsidiary, Ameren Missouri, through an 8-K filing dated October 3, 2025.

Mark C. Birk has retired from his roles as Chairman and President of Ameren Missouri, effective October 2, 2025. This marks the end of Mr. Birk's tenure in these critical positions within the company's largest operating utility.

In response to Mr. Birk's retirement, Michael L. Moehn, currently Ameren Corporation's Senior Executive Vice President and Chief Financial Officer, has been appointed as the Interim Chairman and President of Ameren Missouri.

Mr. Moehn brings a wealth of experience, having previously held the top leadership position at Ameren Missouri from 2014 to 2019 and serving as CFO since 2019. This interim appointment suggests a strategic move to maintain stability and leverage experienced leadership during the transition.

02—Key points

Key Highlights

  1. Mark C. Birk has retired as Chairman and President of Ameren Missouri, effective October 2, 2025.
  2. Michael L. Moehn has been appointed as Interim Chairman and President of Ameren Missouri.
  3. Mr. Moehn currently serves as Ameren Corporation's Senior Executive Vice President and Chief Financial Officer.
  4. Mr. Moehn has prior experience as Chairman and President of Ameren Missouri from 2014 to 2019.
  5. The retirement and interim appointment are effective as of October 2, 2025.
  6. The filing indicates a smooth transition of leadership within Ameren Missouri.

03—Questions

Frequently Asked Questions

  1. Who has stepped down from leadership at Ameren Missouri and what were their roles?

    Mark C. Birk has retired from his positions as Chairman and President of Union Electric Company, doing business as Ameren Missouri.

  2. Who has been appointed to lead Ameren Missouri on an interim basis?

    Michael L. Moehn, currently Ameren Corporation's Senior Executive Vice President and Chief Financial Officer, has been elected as the Interim Chairman and President of Ameren Missouri.

  3. Does Michael L. Moehn have prior experience with Ameren Missouri?

    Yes, Mr. Moehn previously served as Chairman and President of Ameren Missouri from 2014 to 2019.

  4. When are these leadership changes effective?

    The changes are effective as of October 2, 2025.

04—Continue

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