The VS Inventory Activity records that are created when each vendor shipment order is invoiced are used to provide source data for the A/P three-way matching process. The VS records are posted to the GL and they are included on the Unvouchered Inventory report and in the Unvouchered Inventory balance in the GL.
When the vendor invoice for a vendor shipment transaction is received and processed (manually or electronically), the type VS inventory activity records for each invoice are matched up to the invoice itself. Any differences between the invoice and the po prices used for the invoice must be reconciled and adjusted for before the AP invoice can be saved. Once the invoice is saved, the matched up transactions are closed (by matching them to the new ap invoice record) and the amount of the transactions is removed from the Unvouched Inventory report (subledger) and the Unvouchered Inventory general ledger account balance.
Please see the documentation for the Accounts Payable System for more information on the 3 Way Matching process.