The principle of Uberrimae fidei applies to all types of insurance contracts and is a very basic and primary principle of insurance. According to this principle, the insurance contract must be signed by both parties (i.e insurer and insured) in absolute good faith or belief or trust.
The person getting insured must willingly disclose and surrender to the insurer all relevant complete true information regarding the subject matter of insurance. The insurer’s liability is voidable (i.e legally revoked or cancelled) if any facts, about the subject matter of insurance are either omitted, hidden, falsified or presented in a wrong manner by the insured..
The principle forbids either party to an insurance contract, by non-disclosure or mis-representation of a material fact, which he knows or ought to know, to draw the other into the bargain, from his ignorance of that fact and his believing the contrary. The duty of the utmost good faith is implied in insurance contracts because they are entered into by parties who have not the same access to relevant information. In this, they differ from contracts of sale to which the maxim caveat emptor (let the buyer beware) applies.
Although the duty rests upon both parties, it is the duty of the proposer which needs to be discussed in some detail for he usually has the advantage of knowing most of the particulars relating to the subject-matter. Until a definite offer to enter into an insurance contract has been unconditionally accepted the duty of the utmost good faith must be strictly observed. The obligation arises again prior to each renewal and, to a limited extent, when the insured desires an alteration in the policy. In the latter case, he must inform the insurer of any facts material to the alteration.