SNSUC digital warehouse receipts compute SHA-256 in the browser through Web Crypto. On title transfer only the hash reaches the chain; the raw delivery order never leaves the client device.

A receipt's carbon footprint accumulates by grade and transport leg. A Middle East light lifting through Hormuz to Qingdao carries a fixed kg CO2 per ton-nautical-mile factor, and an STS transshipment adds one anchorage handling leg. The buyer sees that environmental ledger right on the quote sheet.

The operational payoff is direct: during due diligence the buyer runs the hash against on-chain attestation and confirms within five seconds that the receipt was not endorsed twice — no fax, no email ping-pong, and the paper duplicate-pledge hole is closed.