Indian Contract Act, 1872
4 [16."Undue influence" defined
(1) A contract is said to be induced by "undue influence" where the relations subsisting between the parties are such that one of the parties is in a position to dominate the will of the other and uses that position to obtain an unfair advantage over the other.
(2) In particular and without prejudice to the generality of the foregoing principle, a person is deemed to be in a position to dominate the will of another-
(a) where he holds a real or apparent authority over the other, or where he stands in a fiduciary relation to the other; or
(b) where he makes a contract with a person whose mental capacity is temporarily or permanently affected by reason of age, illness, or mental or bodily distress.
(3) Where a person who is in a position to dominate the will of another, enters into a contract with him, and the transaction appears, on the face of it or on the evidence adduced, to be unconscionable, the burden of proving that such contract was not induced by undue influence shall lie upon the person in a position to dominate the will of the other.
Nothing in this sub-section shall affect the provisions of section 111 of the Indian Evidence Act, 1872 (1 of 1872).
(a) A having advanced money to his son, B, during his minority, upon B's coming of age obtains, by misuse of parental influence a bond from B for a greater amount then the sum due in respect of the advance. A employs undue influence.
(b) A, a man enfeebled by disease of age, is induced by B's influence over him as his medical attendant, to agree to pay B an unreasonable sum for his professional services, B employs undue influence.
(c) A, being in debt to B, the money-lender of his village, contracts a fresh loan on terms which appear to be unconscionable, It lies on B to prove that the contract was not induced by undue influence.
(d) A applies to a banker for a loan at a time when there is stringency in the money market, The banker declines to make the loan except at an unusually high rate of interest. A accepts the loan on these terms. This is a transaction in the ordinary course of business, and the contract is not induced by undue influence.]