United States v. State

Background

On October 27, 1947, the Court issued a final decree about ownership of lands, minerals, and other natural resources under the Pacific Ocean off California. The Court entered supplemental decrees in 1966 and again in 1977–1981 to further define parts of the boundary. California and the United States asked the Court to identify the federal‑state line with greater particularity. This fifth supplemental decree describes fixed boundary lines and refers to Exhibits A, B, and C, including locations near the Farallon and Channel Islands.

Reasoning

The core question was where to place a precise line that separates state-owned submerged lands from federally owned seabed. The Court located the boundary by giving plane coordinates in the Universal Transverse Mercator system tied to the North American Datum 1983 (equivalent to WGS 84). The decree states that, except for specified exceptions in Section 5 of the Submerged Lands Act, California is entitled to lands, minerals, and resources landward of those coordinates, and the United States is entitled to those seaward of them. The decree also provides that the boundary is immobilized under 43 U.S.C. 1301(b), meaning it “shall not be ambulatory.”

Real world impact

The ruling clarifies which government controls seabed rights and natural resources off California’s coast, including who may grant leases, approve exploration, and collect revenues. Fixing the boundary by coordinates means ownership will not shift with changing shoreline measurements. The Court retained jurisdiction to enter further orders as needed to give the decree effect or to enforce the parties’ rights.