UN made mining firms split seabed claims, then chose first

As the 1970s deep-sea mining rush loomed, negotiators drafting the UN Convention on the Law of the Sea faced a structural problem: only a few wealthy states and their companies had the ships and technology to survey the ocean floor for valuable polymetallic nodule deposits, while the treaty's own International Seabed Authority was designed to hold the seabed's mineral wealth in trust for all countries, including ones with no capacity to survey anything themselves.

The Authority could not solve this by fielding its own survey fleet to check every claim; that defeated the purpose of relying on private capital to do the expensive exploration work at all. It needed a mechanism where the company's own self-interest, not an inspector's judgment, would force it to value the two halves of its claim honestly.

Required applicants to split claims into two halves they certified equal; the Authority picked either, so bias handed away the better half.

Applicant must certify both halves equal, so any bias risks losing the better half.

Authority chooses last, so the applicant's self-interest enforces honesty.

No independent survey needed, saving costs and relying on private capital.

When one party has better information, don't audit their valuation—let them divide the resource and you choose first.

Investors from France, Japan, the USSR, India, China and Korea submitted paired sites under the rule, banking claims for developing states. The banked-site, divide-and-choose mechanism remains the operative rule for every deep-sea mining exploration contract today and stands as one of the few working examples of split-and-choose fairness enforced at full treaty scale.