What happens if a purchasing document status is finally closed?

You can prevent modifications to or actions against completed documents, lines, and schedules by final closing them.

You can't perform certain actions against final-closed entities, such as receive, transfer, inspect, deliver, correct receipt quantities, invoice, return to supplier, or return to receiving. You can approve documents that include final-closed entities, but you can't approve documents that are final closed at the header level. You can print final-closed documents because that has no bearing on your contractual relationship with the supplier.

A schedule is finally closed when an accounts payable clerk indicates a final match while matching an invoice.