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This case (Byrne v Van Tienhoven [1880] 5 CPD 344) demonstrates the principle that an Offer to contract cannot be considered withdrawn until the offeree has received it.

The sequence of events was like this.

• October 1: 'A' posts an order to 'B' 1000 boxes of tin plate.
• October 8: A posts a letter revoking the order
• October 11: B receives A's order
• October 15: B replies, accepting the terms
• October 20: B receives A's revocation

By the 15th, B clearly thinks a contract is in place, and the court agrees. The fact that A revoked the order is irrelevant, as B had accepted before receiving the revocation.