First Deep-Sea Mining Adventure Already Testing the Waters

On October 20, the Marine Minerals Administration (MMA), the Department of the Interior (Interior) agency that now administers offshore mineral leasing, published its first-ever offshore mineral lease sale off American Samoa. The sale, scheduled for November 19, 2026, would offer two leases covering more than 31 million acres of the Outer Continental Shelf (OCS). A Samoan council of chiefs, a Samoan American community group, and the Conservation Council for Hawai’i immediately sued in the District of Hawai’i to stop the sale.

Interior Secretary Doug Burgum announced in September that deep-sea mining permits could come within months, with the American Samoa lease sale being the first step in that sequence. Because the plaintiffs challenge both MMA’s statutory authority and its environmental review, the litigation should offer an early read on how a domestic leasing framework holds up under challenge, a question that will recur as the government also pursues permitting for seabed mining in international areas.

The Lease Sale

The Final Leasing Notice offers two lease areas, OCS-P 0568 and OCS-P 0569, for development of minerals in polymetallic nodule and ferromanganese crust deposits. Each lease would carry a 20-year primary term and a $3,000,000 minimum bonus bid, and MMA would award the leases through an ascending oral auction. MMA has emphasized that a winning bid, by itself, would authorize only preliminary activities, such as mapping, and that a multi-stage post-auction regulatory process would precede any physical exploration, testing, or full-scale commercial harvesting.

The Lawsuit

On October 19, 2026, Faleula o le Manu‘atele (a council of matai, or chiefs, from American Samoa’s Manu‘a Islands), Fa‘asao Amerika Samoa, and Conservation Council for Hawai‘i (collectively, the plaintiffs) sued MMA and Interior Secretary Doug Burgum in the U.S. District Court for the District of Hawai‘i. In their complaint, Faleula o le Manu‘atele v. Marine Minerals Administration, No. 1:26-cv-00543 (D. Haw. filed Oct. 19, 2026), the plaintiffs asked the court to declare the Final Leasing Notice unlawful, to vacate it, and to issue appropriate injunctive relief, all under the Administrative Procedure Act.

The plaintiffs contest MMA’s authority to lease areas for mineral development under the Outer Continental Shelf Lands Act or areas they claim are subject to treaties benefiting Samoans. Even if such authority exists, the plaintiffs contend MMA violated the National Environmental Policy Act by failing to analyze alternatives that would exclude certain areas from development or evaluate the effects of mineral exploration, testing, development, and mining in an environmental impact statement.

Two related suits, both in the U.S. District Court for the District of Hawai‘i, challenge the National Marine Fisheries Service’s Endangered Species Act review of the proposed sales. These suits contest the National Marine Fisheries Service’s conclusion that mining “is not likely to adversely affect” species protected under the Endangered Species Act.

The Broader Federal Push

The American Samoa lease sale is just one piece of a larger effort. In Executive Order 14285 (April 24, 2025), the president directed agencies to accelerate seabed mineral exploration and development, and the White House fact sheet describes the goal as establishing U.S. leadership both within and beyond national jurisdiction.

On August 17, 2026, MMA published a Proposed Leasing Notice for a lease sale in federal waters off the Commonwealth of the Northern Mariana Islands. The notice identifies five lease areas totaling roughly 67 million acres and proposes a December 16, 2026 auction. MMA has said that the proposed notice does not affirm that a sale will be held, but we anticipate a Final Leasing Notice to publish at least 30 days before any sale similar to the American Samoa lease announcement.

For areas beyond national jurisdiction, the National Oceanic and Atmospheric Administration is already in the process of reviewing at least one consolidated exploration license and commercial recovery permit application under the U.S. Deep Seabed Hard Mineral Resources Act.

What Comes Next

With the sale set for November 19, 2026, the plaintiffs’ request for injunctive relief tees up major issues for preliminary consideration on the likelihood of success on the merits of the case. Given the political importance of mineral development on the OCS and beyond, this an important case and one worth following.

This post is as of the posting date stated above. Sidley Austin LLP assumes no duty to update this post or post about any subsequent developments having a bearing on this post.