Talen Energy files 8-K: director / officer changes, Regulation FD disclosure, other material event

Item 5.02. Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On September 29, 2026, as part of its coordinated, on-going succession and retention planning, Talen Energy Corporation (the “Company”) announced that the Company’s board of directors (the “Board”) has named Terry L. Nutt as the Company’s next Chief Executive Officer (“CEO”) and President, effective January 1, 2027 (the “Effective Date”), at which time Mr. Nutt will also join the Board. As further described below, Mr. Nutt has entered into a second amended and restated employment agreement (the “Employment Agreement”) reflecting his new responsibilities as CEO and continued responsibilities as President that will become effective on the Effective Date.

In addition, Mark “Mac” A. McFarland, the Company’s current CEO, has given the Company notice of his intent to step down as CEO and as a member of the Board, effective on the Effective Date. Following the Effective Date, Mr. McFarland will serve as a Senior Advisor to the Company beginning on January 1, 2027 until his retirement on March 1, 2027 (the “Separation Date”). As further described below, Mr. McFarland has entered into a transition and retirement agreement with the Company (the “Transition Agreement”).

Mr. Nutt was not appointed to his new positions under any arrangement or understanding between him and any other person. There are no transactions with Mr. Nutt that would be reportable under Item 404(a) of Regulation S-K and no family relationships exist between Mr. Nutt and any of the directors or other officers of the Company. Mr. McFarland’s retirement is not the result of any disagreement with the Company related to its operations, policies, or practices.

Biography of Mr. Nutt Mr. Nutt , age 50, has served as the Company’s President since December 2025, prior to which he served as the Company’s Chief Financial Officer from July 2023 through December 2025. He has over 25 years of experience in the energy industry, including time spent at independent power producers and energy trading firms. From 2018 until 2023, he served as Chief Financial Officer and Managing Director for EDF Trading North America (“EDF”), the energy commodity trading subsidiary of Électricité de France (EDF) S.A., a multinational energy utility headquartered in France. Prior to his service at EDF, Mr. Nutt served in multiple senior finance positions at Vistra Corporation (and its predecessor entities) (“Vistra”), including as Senior Vice President and Controller and Senior Vice President of Risk Management. Prior to his time at Vistra, Mr. Nutt worked in various finance roles at Dynegy Inc. Mr. Nutt earned his M.S. in Accounting and his B.B.A., summa cum laude, from Texas A&M University. Mr. Nutt has also completed the MIT Nuclear Reactor Technology Course for Utility Executives.

Employment and Transition and Retirement Arrangements – Named Executive Officers

Salary and Incentive Compensation Changes

In connection with Mr. Nutt’s appointment and the approval of his revised E mployment Agreement, the Board set his base salary at $1,200,000; target short-term annual incentive bonus at 135% of base salary; and target grant date value of long-term incentive award amounts at 700% of base salary.

In connection with Mr. Nutt’s appointment, he entered into the Employment Agreement, effective January 1, 2027, with an initial term through February 28, 2028 (subject to automatic annual renewals thereafter unless Mr. Nutt or the Company provides 90 days’ written notice of their intent not to extend the term). The terms of Mr. Nutt’s existing employment agreement will continue to apply until January 1, 2027.

The Employment Agreement provides that, in the event that Mr. Nutt’s employment is terminated by the Company without Cause, the Company does not renew the term of the Employment Agreement, or Mr. Nutt resigns for Good Reason (each, as defined in the Employment Agreement and herein, a “Qualifying Termination”) and such termination is not on or within 18 months following a Change of Control (as defined in the Employment Agreement), Mr. Nutt will receive any earned but unpaid annual bonus for the year preceding the year in which the termination occurs (the “Prior Year Bonus”) and, subject to Mr.

Nutt experiences a Qualifying Termination within 18 months following a Change of Control, he will receive the Prior Year Bonus and, subject to his execution and nonrevocation of a release in favor of the Company and continued compliance with his restrictive covenant obligations, (i) a lump sum equal to 2.99 times the sum of his annual base salary and target annual bonus, (ii) a pro-rated target bonus amount for the year of termination, and (iii) eligibility for COBRA Continuation at a monthly rate that is no greater than the premiums he paid for coverage under the Company’s group health plan immediately prior to the termination date for up to 36 months. In the event Mr. Nutt’s employment is terminated due to Mr.

Nutt’s death or disability, he shall receive (i) the Prior Year Bonus, (ii) a pro-rated portion of his target bonus for the year of termination, and (iii) eligibility for COBRA Continuation at a monthly rate equal to the Company’s full COBRA rates for up to 36 months. Additionally, where Mr. Nutt provides 90 days’ notice on a non-renewal of the term of the Employment Agreement, he shall be entitled to receive the Prior Year Bonus, subject to his execution and nonrevocation of a release of claims in favor of the Company and continued compliance with his restrictive covenant obligations.

Under the terms of the Employment Agreement, Mr. Nutt is subject to perpetual confidentiality, assignment of intellectual property and non-disparagement covenants as well as non-competition and non-solicitation covenants applicable during employment and for one year thereafter.

The foregoing description is qualified in its entirety by reference to the full text of the Employment Agreement, a copy of which is filed as Exhibit 10.1 to this Current Report on Form 8-K (this “Report”) and which is incorporated by reference into this Item 5.02.

In connection with Mr. McFarland’s retirement, Mr. McFarland entered into the Transition Agreement with the Company, dated as of September 28, 2026, which provides for a transition from his current role as CEO and as a member of the Board to a role as Senior Advisor to the Company, reporting to the Chairman of the Board, beginning on January 1, 2027 and ending on the Separation Date. Mr. McFarland will be paid $100,000 for his services as a Senior Advisor and will continue to receive his current benefits through the Separation Date (other than any new grants of equity). Upon his separation, subject to his execution and non-revocation of a general release of claims in favor of the Company and his continued compliance with his restrictive covenant obligations to the Company, its subsidiaries, and affiliates, he will receive (x) the COBRA Continuation for up to 36 months and (y) his annual bonus for the 2026 fiscal year, based on actual performance.

The foregoing description is qualified in its entirety by reference to the full text of the Transition Agreement, a copy of which is filed as Exhibit 10.2 to this Report and which is incorporated by reference into this Item 5.02.

On September 29, 2026, the Company issued a press release regarding the executive matters described above, and additionally announcing its entry into the capacity monetization transaction, the upsize of the Company’s share repurchase program and its entry into accelerated share repurchase agreements, each as described below, a copy of which is furnished as Exhibit 99.1 to this Report and which is incorporated by reference into this Item 7.01.

The information provided under this Item 7.01 and in Exhibit 99.1 to this Report is being furnished and shall not be deemed “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that Section. Such information shall not be incorporated by reference into any registration statement or other document pursuant to the Securities Act of 1933, as amended, or the Exchange Act.