16. What are release codes in release procedure? Two-character identifier with which a person responsible for processing a document can release (approve) an item of a purchase requisition, a complete purchase requisition, or a complete external purchasing document, or cancel such release (that is, revoke a previously granted approval). If a link to SAP Business Workflow has been defined for the release code, the person involved can also refuse to effect release (withhold approval), thus rejecting the relevant item or document.