To the contrary i have seen at least 50 approval letters and many are intentionally vague and ambiguous on purpose. We find it very difficult to figure out the intentions of the lender though we suspect it is to keep their options open down the line. If it does not say the lender agrees to accept the proceeds as full and final satisfaction and agrees to forego deficiency right it is ambiguous. I have seen letters some felt were clear only to have the lender come after the seller after the short sale closes. Sometimes we get them and explain the risks to the seller then let them decide what they want to do. We recently had a non recourse 2nd try to go after a client after issuing a good but not perfect release. Ironically it was PNC (though a different lender under the PNC umbrella). After some legal letters explaining the case law we had on our side they have agreed to drop the matter.