While going over the FulfilmentCancellation message I noticed the following: cac:BuyerCustomerParty [1..1] The buyer. cac:SellerSupplierParty [1..1] The seller. Both of these elements are mandatory in the message. But the definition of this document is: A document used to cancel an entire fulfilment document (Despatch Advice or Receipt Advice). and when you look at both the DA and RA you see the following: DA cac:DespatchSupplierParty [1..1] The despatch party. cac:DeliveryCustomerParty [1..1] The delivery recipient. cac:BuyerCustomerParty [0..1] The buyer. cac:SellerSupplierParty [0..1] The seller. cac:OriginatorCustomerParty [0..1] A customer party as originator. RA cac:DeliveryCustomerParty [1..1] The customer party. cac:DespatchSupplierParty [1..1] The supplier party. cac:BuyerCustomerParty [0..1] The buyer. cac:SellerSupplierParty [0..1] The seller. so in both the DA and RA documents the only required party elements are the cac:DespatchSupplierParty and cac:DeliveryCustomerParty and the other party elements are optional. Based on this is very " strange" that in order to create document to cancel one of these documents you now have to provide information that you might not have available in the original context. (ie the cac:BuyerCustomerParty and cac:SellerSupplierParty ) Ideally the same two elements that are mandatory in DA/RA (cac:DespatchSupplierParty and cac:DeliveryCustomerParty ) would be made mandatory in the FulfilmentCancellation but that is not backwards compatable. So I would suggest to make both the cac:BuyerCustomerParty and cac:SellerSupplierParty optional in the FulfilmentCancellation document so that people can create that document based on the same information that was available during the DA/RA creation.