Incorporation by Custom

McCutcheon v David MacBrayne Ltd [1964] 1 WLR 430, per Lord Devlin:

The fact that a man has made a contract in the same form 99 times (let alone three or four times which are here alleged) will not of itself affect the 100th contract in which the form is not used. Previous dealings are relevant only if they prove knowledge of the terms, actual and not constructive, and assent to them. If a term is not expressed in a contract, there is only one other way in which it can come into it and that is by implication.

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