Butler Machine Tool Co Ltd v Ex-Cell-O Corp (England) Ltd
Court of Appeal  1 WLR 401
An offer was containing a price escalation clause. A counter offer was then made without this clause; it contained a detachable receipt which the company (original offeror) sent back with a notation that they assumed it was on their terms.
There was an offer, then a counter-offer, then the counter-offer was accepted because the detachable form was SIGNED, notwithstanding their reference to the original terms. Lord Denning MR noted that: ‘In many of these cases our traditional analysis of offer, counter-offer, rejection, acceptance and so forth is out-of-date. … The better way is to look at all the documents passing between the parties and glean from them, or from the conduct of the parties, whether they have reached agreement on all material points, even though there may be differences between the forms and conditions printed on the back of them. … Applying this guide, it will be found that in most cases when there is a “battle of the forms” there is a contract as soon as the last of the forms is sent and received without objection being taken to it. … The difficulty is to decide which form, or which part of which form, is a term or condition of the contract. In some cases the battle is won by the man who fires the last shot. He is the man who puts forward the latest terms and conditions: and, if they are not objected to by the other party, he may be taken to have agreed to them. … In some cases, however, the battle is won by the man who gets the blow in first. If he offers to sell at a named price on the terms and conditions stated on the back and the buyer orders the goods purporting to accept the offer on an order form with his own different terms and conditions on the back, then, if the difference is so material that it would affect the price, the buyer ought not to be allowed to take advantage of the difference unless he draws it specifically to the attention of the seller. There are yet other cases where the battle depends on the shots fired on both sides. …’