Hello,

I think idea of authorization in IFS is that you are expected to authorize final cost/expense value (i.e. final purchase price = matching result) irrespective of original price/value on PO. 

One idea I could suggest is automatic authorization: in case of invoice is perfectly matching PO value (within specific tolerance limits) - invoice can be authorized automatically without any additional manual check. In case of differences resolved by manual matching (and PPV is usually identified by manual matching, if not result of currency conversion differences), manual authorization is required.

Yes you are right. this i allready suggested to the customer. So this means whenever a pricedifference between PO and Invoice occurs, they must add the authorizer manually to the Posting line. But the goal would be whenever a pricedifference occurs it must be authorized additionally by the purchasing departement. So this means when you do the matching and you change during the matching the invoice Price unit, the M19/M20 is created automatically. This posting type is only seen in the TAB cost Posting and not as a posting line which you need to authorize. So only workarround would be adding the purchasing department to the original posting line as an additional authorizer. but this is manual work. 

Using automatic authorization and purchasing department ALWAYS part of approval path is one of the options available. Perhaps best one.

Amount to be authorized in case of matching with invoiced price changed is already containing PP variation amount, so M19/M20 cannot be authorized separately. And there is no way to automatically assign different routing rule to not perfect matching proposal line.

You can consider tolerance functionality as well - if matching difference is within tolerance, then tolerance posting can be created as separate posting line using specific posting control - and specific routing.