How should sales of ISCC stock to non-ISCC contracts/buyers be reflected in the UDB?

The UDB operates such that transactions are always seller-initiated. This means that only an Economic Operator (EO) can register a transaction and each transaction will be reviewed (accepted or rejected) by the counterparty/buyer. Often, the final market of the material (liquid biofuels, solid biofuels, etc.) is not clear to the EO at the beginning of the supply chain. Therefore, ISCC EU-certified EOs are advised to enter their transactions in the UDB. Should this material flow reach a stage in the supply chain where it is no longer in the scope of the UDB, e.g. ISCC PLUS, the UK market, etc., then the UDB “book-out” feature can be used. Via this feature, it is possible to “book-out” consignments of the UDB while ensuring UDB registration and traceability for the upstream supply chain.