The dx.system.account.uniqueness system property indicates whether an account is unique within the scope of the partner or within the scope of B2B Data Exchange.
If the dx.system.account.uniqueness system property is set to PARTNER, the account is unique within the scope of the partner. You can assign the same account number to multiple partners. If you do, the B2B Data Exchange Server determines the profile based on the application, partner, and account number.
If the dx.system.account.uniqueness system property is set to SYSTEM, the account is unique within the scope of B2B Data Exchange and you cannot use the same account number more than once. If the dx.system.account.uniqueness system property is set to SYSTEM, the B2B Data Exchange Server determines the profile based on the application and account number.