Multistate Fannie Mae Assignment of Deed of Trust — Single Family is a document that assigns an existing Fannie Mae-backed mortgage loan from one party to another. It is used when the original lender wishes to transfer ownership of the loan to a third party. The document records the transfer of the loan and the terms of the new loan agreement. It is used to transfer loans between Fannie Mae-approved lenders and to transfer the mortgage to another party when the original borrower defaults on the loan. There are two types of Multistate Fannie Mae Assignment of Deed of Trust — Single Family: Assumption of Deed of Trust and Assignment of Deed of Trust. An Assumption of Deed of Trust occurs when the new lender assumes the existing loan and liability, while an Assignment of Deed of Trust transfers the loan and liability to the new lender. Both types of documents require the signatures of all parties involved in the transaction and must be filed with the local county recorder.