What is an Assignment And Assumption Agreement? An assignment and assumption agreement transfers one party's rights and obligations to a third party.In a Novation Agreement, the original contract is replaced entirely, with a new party taking the place of the original party. This assignment and assumption agreement template includes a novation agreement and may be used to transfer an agreement from one party to another. Novation clause samples. 7. An assignment and assumption of lease is a legal real estate document that allows one party to transfer rights and obligations of a lease to another party.