(7)In order to respect the principle of proportionality, the transaction data templates for non-performing credit agreements should require different information depending on the nature and size of the non-performing credit agreements and should specify the data fields that have to be completed or specify the circumstances under which it is not mandatory to complete certain data fields. For the same reason, credit institutions should not be obliged to complete all data fields in the transaction data templates for all transactions. Such transactions should involve the sale or transfer of: (1) a single non-performing credit agreement; (2) several non-performing credit agreements linked to one single borrower; (3) non-performing credit agreements that are part of syndicated credit agreement facilities; (4) non-performing credit agreements linked to a borrower that is domiciled outside of the Union; (5) non-performing credit agreements that have been acquired from an entity that is not a credit institution, as in such situations credit institutions may not have all the information required to complete all data fields; (6) non-performing credit agreements to natural persons, where those transactions concern small unsecured credit agreements that are outside the scope of Directive 2008/48/EC. The same approach should apply in the case of a sale or transfer of non-performing credit agreements between credit institutions that belong to the same group.