Where there is a doubt about the meaning of a grant, the doubt will be resolved against the grantor. Similarly words in a contract (particularly exclusion clauses) are construed against the person for whose benefit they are inserted. However, the rule is reversed in the case of a grant by the Crown.
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186 6.12"Where two constructions of an instrument are equally plausible, upon one of which the instrument is valid, and upon the other of which it is invalid, the court should lean towards that construction which validates the instrument.