The initial contract must provide for the possibility of assignment by one of the initial contracting parties. The assignor must agree to assign their rights and duties under the contract to the assignee. The assignee must agree to accept, or "assume," those contractual rights and duties.
Assignment of contract is when one party within a contract assigns the rights and/or obligations of that contract to another party outside of it. The party who is assigning the contract is known as the assignor and the party receiving the rights and responsibilities of the contract is the assignee.
The assignor must agree to assign their rights and duties under the contract to the assignee. The assignee must agree to accept, or "assume," those contractual rights and duties. The other party to the initial contract must consent to the transfer of rights and obligations to the assignee.
In general, it is not legal to change a contract after signing without the agreement of both parties. Once a contract has been signed, it becomes a legally binding agreement, and any changes to its terms must be done in a formal and transparent manner.
An assignment will generally be permitted under the law unless there is an express prohibition against assignment in the underlying contract or lease. Where assignments are permitted, the assignor need not consult the other party to the contract but may merely assign the rights at that time.