Marathon Oil Group Trust

The trust's assets are managed by the United States Steel Corporation Pension Fund team, a relationship dating back to when U.S. Steel (then USX) owned Marathon Oil before its 2002 spin-off. This arrangement survived the corporate separation and the trust's named investment managers oversee portfolio allocations independently of Marathon's subsequent parent, ConocoPhillips.

ConocoPhillips acquired Marathon Oil Corporation in November 2024 for $22.5 billion. Despite this acquisition, the Marathon Oil Group Trust's assets remain under the management of the U.S. Steel Pension Fund, not under ConocoPhillips' control. The trust is a separate legal entity holding retiree obligations distinct from the corporate operating company.

Confirmed commitments include stakes in Westbrook Real Estate Fund III and Westbrook Real Estate Fund IV, both U.S.-focused mixed-use vehicles. The trust also directly owns the Marathon Oil Tower at 5555 San Felipe Street in Houston, indicating a dual approach of fund investing and direct property ownership.

The trust's portfolio includes a Gulfstream G550 and a British Aerospace 125-700A corporate aircraft. These aviation assets likely stem from the legacy Marathon Oil corporate fleet and were retained within the retirement trust rather than transferred back to the operating company.

The trust functions as a legacy defined-benefit plan for former Marathon Oil employees. It does not appear to have active participants accruing new benefits but continues to hold and manage assets to meet existing retiree obligations. It operates outside the standard corporate governance structure of both Marathon and ConocoPhillips.