Novation: What's the difference? An assignment and assumption agreement transfers one party's rights and obligations to a third party.This Standard Document contains provisions to incorporate an assumption of the delegated obligations and an optional novation into the assignment agreement. 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. This assignment and assumption agreement template includes a novation agreement and may be used to transfer an agreement from one party to another. In an Assignment Agreement, the original contract remains in effect, with the assignor transferring certain rights or obligations to the assignee.