Deterministic ISIN check before routing an order or paying a market-data API: structure regex (2-letter country or XS/EU, 9-char NSIN, check digit) and the Luhn checksum over the base-36 expansion. Query: ?isin=US0378331005. Returns valid, country_code, nsin, check_digit and is_international. A corrupted ISIN means a rejected order or the wrong instrument. Pure offline computation, 1y cache.
| Network | Scheme | Amount | Pay To |
|---|---|---|---|
| Base | exact | $0.002000 USDC | 0x6ab8...2dff |