Acceptance of offer

What does Acceptance of offer mean in American Law?

The definition of Acceptance of offer in the law of the United States, as defined by the lexicographer Arthur Leff in his legal dictionary is:

One of the critical moves in the contract formation process. Assuming the existence of consideration, and parties with legal capacity, the acceptance of an offer creates a contract. “Accept” in this context, then, is closely cognate to “agree,” and thus runs into all the difficulties to be expected when the idea of agreement is broached. The situtation is this: The offeror projects toward the offeree words proposing a transaction, i.e., the “offer.” The offeree replies with other words. Are those words an “acceptance” such that there now exists a contract, and if so, what are the terms thereof? The first question involves the content of the offeree’s replying words: How closely need they approximate the words of the offer, how much in the way of new matter may be added, before the reply is not an “acceptance” of the offer, but a “counteroffer,” i.e., a new offer which must now be accepted by the original offeror (now the new offeree) before a contract will arise? See also battle of the forms. The second cluster of problems may arise even when there is no possible claim that the offeree’s reply could be construed as a counteroffer, e.g., when it takes the form of

an oral “I accept your offer,” or a written signature on the offering document. The key question then is this: What is the relevance, if any, of .the offeree’s subjective understanding or intention once he has apparently agreed to the offer? The modern answer, which is sometimes called the “objective theory of contract,” has been that if the offeree, having received a communication which a reasonable person in his position would understand to be an offer, communicates a reply (which may take the form of words or deeds) which a reasonable person in the position of the offeror would take to be an acceptance, then [he] has accepted the offer, and is bound to all of the terms thereof. This is the case even if (a) he did not subjectively understand the terms of the offer (or indeed that it was one); or (b) he did not subjectively mean to accept the offer. This view of “acceptance of an offer” constitutes an almost perfect exemplar of the philosophical concept of a performative utterance.

The U.C.C., notably in §§ 2-204, 2-206, and 2-207, contains provisions B509 directed toward offer and acceptance and some of the problems mentioned above, at least with respect to contracts for the sale of goods. Moreover, the rigor of this objective theory has from time to time been softened with respect to persons having formal capacity to contract, but arguably lacking full power to protect themselves in the making of contracts, e.g., consumers.