In our business we regularly have to issue a joint check (or two party check) made out to vendor1 AND vendor2. Vendor 1 will provide an invoice which includes their suppliers (which are to be paid directly by us) When we make a partial payment on an invoice it would be nice to be able to easily enter the 2nd party. The real magic would be if this were available via API and we could use an integration to automatically enter the payments from our system which already captures all of the 2 party info and amounts.