Contracts/Mirror image rule
Template:Unreferenced Template:Contract law
In the law of contracts, the mirror image rule, also referred to as an unequivocal and absolute acceptance requirement states that an offer must be accepted exactly without modifications. The offeror is the master of his own offer. An attempt to accept the offer on different terms instead creates a counter-offer, and this constitutes a rejection of the original offer. (Restatement(2d) Contracts §59).
This position is adhered to in Australia (New South Wales). If a person were to accept an offer, but make a modification, then they are actually rejecting the offer presented to them and are proposing a counter-offer [Masters v Cameron (1954) 91 CLR 353]. That modifying party is then the one making a new offer, and the original offeror is now the one who has to accept.
In the United States, this rule has been altered with respect to merchants dealing in the sale of goods under the Uniform Commercial Code (UCC Section 2-207). In such situations, an acceptance that does not match the terms of the offer is nonetheless effective as long as the material terms are agreed upon. Example: Larry the T-shirt printer (merchant) offers to make and sell 1,000 yellow T-Shirts with "Bring the Ruckus" on the back for $100 to Vinny of Vincent's Shirt Barn (merchant). Vinny accepts the offer and writes change to "Bring da Ruckus" on the back of the invoice. This constitutes acceptance and the contract will be enforceable in spite of the alteration because the change is immaterial and both are merchants. The changed or additional terms in the acceptance will become part of an agreement between merchants unless the offer limits acceptance to the terms of the offer (e.g.,'no substitutions'), the terms materially alter the offer, or the other party objects to the new terms within a reasonable time. (UCC 2-207 (2)(a)-(c)). When both parties are not merchants but the transaction is covered by the UCC (for example, when Vinny agrees to sell t-shirts to a customer), then any additional terms will be proposals for addition to the contract but will not automatically become a part of the bargain. (UCC 2-207(2)). ko:경상의 원칙
