Ratification: In simple terms, the agent acts without authority but when the principal learns what has happened, he/she decides to ratify the agreement that has been made and to adopt the contract made by the agent purportedly on his/her behalf. Ratification can be express or can be implied from the conduct of the parties. In the case of contracts required to be in writing, ratification need not be written but if the agent has signed a deed on behalf of the principal, then ratification must be in the form of a deed.