The rule in L'Estrange v Graucob — that a party who signs a contractual document is bound by its terms — does not apply until it has been established as a question of fact that the document in question was intended by the parties to form part of their contractual arrangement. The same reasonable notice test applies to both signed and unsigned documents when determining incorporation of terms, though signature is a powerful (but not conclusive) indication of intention to be bound. Where a contract is formed by a series of communications and conduct, conditions on the reverse of one document in the series (such as a credit application) may not be incorporated even though signed, if the party relying on them did not do what was reasonably sufficient to bring them to the other party's attention.
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