OBERNDORF WILLIAM E

William E. Oberndorf is an investor and founder of SPO Partners who has acted as a controlling person of investment vehicles that file institutional investor disclosures with the SEC. Public filings record his substantial, disclosed holdings and director-level relationships with several publicly traded companies.^[1]

Career Background

• Founded and led investment vehicles (SPO Partners and related entities) that file Form 13F and Schedule 13D/G disclosures as institutional investors.^[1]
• Served in board and investor roles across multiple companies, with public biographies and filings naming Calpine and other corporate directorships.^[2]
• Participated as a controlling person in SPO Advisory / SPO Partners groups that have appeared as reporting persons in issuer filings and proxy materials.^[3]

Current Positions

• Significant shareholder / reporting person associated with SPO Advisory / SPO Partners — reflected in SEC institutional and Section 16 filings.^[1]
• Identified in public company filings and proxy statements as a disclosed investor or board-affiliated reporting person for issuers such as Cabot Corporation (CBT) and Calpine Corporation (CPN).^[3]

SEC Filing Context

• Files and appears as a reporting person in Form 13F institutional holdings reports and in Section 16 filings (Forms 3/4) submitted to the SEC, indicating sustained institutional investment activity.^[1]