Marine Petroleum Trust is a passive royalty trust created in 1956 that holds overriding royalty interests (ORIs) in oil and natural gas leases in the Gulf of America, offshore Texas and Louisiana. The Trust earns a royalty equal to three-quarters of 1% of the wellhead value of oil, gas, and other minerals produced and sold from the covered leases. It collects these royalties from working interest owners who actually drill and operate the leases, then distributes substantially all cash to unitholders quarterly. The Trust has no employees and is administered by its Trustee, Argent Trust Company. Marine's wholly owned subsidiary, Marine Petroleum Corporation, holds title to certain offshore Louisiana interests and remits 98% of royalties collected to the Trust, retaining 2%. Arena Energy is currently the sole source of royalty revenues, accounting for 100% of royalties received. Revenue is driven primarily by oil prices, which accounted for roughly 94% of royalties in the most recent fiscal year, with natural gas and natural gas liquids making up the rest. The underlying royalty interests are depleting assets — production reduces remaining reserves, and the Trust cannot reinvest, acquire new interests, or replace depleted ones. The Trust is scheduled to terminate on June 1, 2041, unless unitholders vote to extend it.