Permian Basin Royalty Trust, structured as an express trust, primarily holds overriding royalty interests in various oil and gas properties across the United States. Its assets notably include a 75% net overriding royalty stake in the Waddell Ranch properties, situated in Crane County, Texas. These holdings encompass fields such as Dune, Sand Hills (Judkins, McKnight, and Tubb), University-Waddell (Devonian), and Waddell.