The term estoppel is said to have been derived from the French term 'estoup' which means 'shut the mouth'. The doctrine of estoppel is a rule of evidence contained in Section 115 of the Indian Evidence Act. When one person by his declaration , act or omission intentionally caused or permitted another to believe a thing to be true and act upon such belief, neither he nor his representative shall be allowed in any suit or proceeding between himself and such person or his representative to deny the truth of that thing.
The law recognises different kinds of estoppel. They are as follows:
(1) Estoppel by Record
It results from the judgement of a competent court. If a judgement has become final, a party to the dispute has no right to say against the judgement. It is contained in Sections 40 to 44 of the Indian Evidence Act.
(2) Estoppel by Deed
When a person agrees to another in a matter by a deed acknowledging the same, the person cannot say against the contents.
(3) Estoppel in conduct
This happens with the act or conduct or misrepresentation of one which has induced a chage of position in another.