A standard form contract drafted by one party (usually a business with stronger bargaining power) and signed by the weaker party (usually a consumer in need of goods or services), who must adhere to the contract and therefore does not have the power to negotiate or modify the terms of the contract. Adhesion contracts are commonly used for matters involving insurance, leases, deeds, mortgages, automobile purchases, and other forms of consumer credit. Also known as adhesive contract; adhesory contract; adhesionary contract; take-it-or-leave-it contract; leonine contract.
Courts carefully scrutinize adhesion contracts and sometimes void certain provisions because of the possibility of unequal bargaining power, unfairness, and unconscionability. Factoring into such decisions include the nature of the assent, the possibility of unfair surprise, lack of notice, unequal bargaining power, and substantive unfairness. Courts often use the “doctrine of reasonable expectations” as a justification for invalidating parts or all of an adhesion contract: the weaker party will not be held to adhere to contract terms that are beyond what the weaker party would have reasonably expected from the contract, even if what he or she reasonably expected was outside the strict letter of agreement.