The purpose of the UpdateRequisition is to communicate Updates to an existing request for goods or services. This Update must refer to the original document and/or item requested. The Update processing assumes replacement of fields sent, with the exception of: the key fields for the Order and Line. If any of the Field Identifiers above require changing, that constitutes a cancellation of the request and/or the addition of another Requisition. Is where the information that the BOD message carries is provided, in this case UpdateRequisition. The information consists of a Verb and one or more Nouns. The verb (Update) indicates the action to be performed on the Noun (Requisition).