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This case ([1976] 1 WLR) demonstrates that if a party in a commercial agreement wishes to claim that an agreement is not intended to be legally binding, it has the evidential burden of proof. In this case only one of the parties to the alleged agreement was a company, the other were consumers, but the principle remains the same.

In 1976 Esso manufactured a large number of coin-like tokens carrying the likenesses of the England World Cup football team. These were to be offered to motorists for every four gallons of petrol purchased from Esso petrol stations. The question naturally arose whether someone, somewhere ought to be paying VAT in respect of these coins.

Esso's defence was that the arrangement with the public was of the form of a gift, and was not a commercial arrangement at all. The coins, it argued, were not sold and therefore not subject to VAT.

Customs and Excise argued, successfully, that the arrangement was a commercial contract with the public; it was set up to entice people to buy a product, and the transaction itself took place in the context of a sale-purchase interaction.

In the end, although Esso lost the argument they won the case; the House of lords ruled that although the public were offering a consideration for the coins, the consideration was not monetary, it was the promise to buy petrol. As the coins were not exchanged for money, they weren't subject to VAT.