SAP Materials Management
Basics :
Vendor Invoices received from the vendor can be booked in SAP either with reference to PO (Purchase order) or can be directly booked in finance module based on the business process. Duplicate vendor invoice check is a standard SAP functionality for checking and warning the user for potential duplicate invoices. Invoices booked in SAP with reference to PO has better control on duplicates when compared to finance invoices as the 3 way match in the logistics process avoids duplicate invoice payments. But in case of finance invoices , since there is no preceding document invoices should be properly reviewed for duplicate before posting.
Duplicate Invoice Check in SAP
SAP has standard criteria for matching potential duplicates. Few of these criteria can be configured for PO based invoices.
The above mentioned criteria are fixed for FI invoices.
There is a little flexibility when it comes to PO based invoices .
Company Code , Invoice date and reference field can be turned on/off baed on company code for duplicate invoice using transaction code : OMRDC.
Reference Documents:
2495634 - Duplicate Invoice check fails in FB60
https://launchpad.support.sap.com/#/notes/0002495634
2036775 - Duplicate Invoice Check in Logistics Invoice Verification
https://launchpad.support.sap.com/#/notes/2036775