Hi Jagjeet:
I contacted the team responsible for invoicing at the Ariba Network. Companies may have a variety of information needs and the method to collect information can vary, but the Ariba Services team can help to configure the Ariba Network to align with any approach.
Here's a link to an article at Ariba Connect that addresses this topic:
https://connect.ariba.com/KAAcontent2/1,,162952,00.html?bypass=1
I hope this information helps.
Debbie Curtis-Magley
Ariba Exchange Community Manager