The check for duplication of invoice entry aims to avoid invoices being accidentally created and paid twice.

When entering an invoice, the system first checks whether the Logistics Invoice Verification invoice documents have already been created. Only invoices with errors or those entered for invoice verification in the background are checked. The system then checks whether any FI documents have already been created by Logistics Invoice Verification, and which of the documents fulfill the relevant criteria.

Only invoices are checked. When you enter credit memos or subsequent debits or credits, the system does not check for duplicate invoices in Logistics. When you create a duplicate invoice, the system displays a warning or error message, depending on your settings in Customizing.

If a previously created document is canceled and then created again, the system does not display a message.

One of the following checks is performed in Financial Accounting, depending on the entry in the Reference field:

1. If a reference document number is given in the current invoice or credit memo, then the system checks for previously posted invoices or credit memos in Financial Accounting that match all the following attributes:

• Company code
• Vendor
• Currency
• Document date
• Reference document number

2. If no reference document number is given in the current invoice or credit memo, then the system checks for previously posted invoices or credit memos that match all the following attributes:

• Company code
• Vendor
• Currency
• Document date
• Amount in document currency

Your system settings determine whether the system sends a warning or error message when it finds an invoice or a credit memo that matches all the relevant attributes.

The system only checks for duplicate invoices in Logistics Invoice Verification if you enter the reference document number when entering the invoice.

In the Implementation Guide (IMG) for Logistics Invoice Verification, you can define that the following characteristics are not checked:

• Reference document number
• Invoice date
• Company code

The result of this is that the system is more likely to find a duplicate invoice, as it checks fewer characteristics.

During the check for duplicate invoices, the system compares the following entered attributes in the standard system in Logistics Invoice Verification:

• Reference document number
• Invoice date
• Gross invoice amount
• Currency
• Vendor
• Company code

In this example, the fields reference document number and company code are not selected in Customizing for Logistics Invoice Verification. This means that these characteristics will not be checked.

Now you enter a new invoice as set out in the example. The reference document number and the company code are not the same, all the other characteristics have the same values. The system displays a message telling you that the invoice is a duplicate entry.

If, for example, the reference document number is selected in Customizing, then the system checks this and recognizes that this is different from the previously entered invoice. No message is displayed.