This is Fortune 500 Power Moves, a column tracking executive shifts—from appointments and promotions to resignations and retirements—within the highest ranks of Fortune 500 companies.

Below is a recap of the C-suite developments at America’s highest-revenue-generating companies announced between Sept. 27-Oct. 3, organized by sector. Titles included in this roundup: CEOs (Chief Executive Officers), CFOs (Chief Financial Officers), COOs (Chief Operating Officers), and Chief Information Officers (CIOs). We also include CTOs (Chief Technology Officers), CHROs (Chief Human Resources Officers), Chief People Officers, CMOs (Chief Marketing Officers), and Chief Customer Officers when there are Power Moves within the Fortune 500 announced pertaining to those roles.

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Energy

Occidental Petroleum (No. 159) promoted Richard Jackson to SVP and COO. Jackson has served as SVP and President, U.S. Onshore Resources and Carbon Management, Operations at the company since 2020.