37. Instances where relief will not be granted.

In the following cases the court will not intervene, despite the mistake:


    (1)     where, although the parties are not in fact ad idem1, there is a consensus by estoppel which is accurately recorded in any document2;


    (2)     where, although there is a common mistake, the parties' agreement (accurately recorded) on its true construction validly allocates the risk of mistake to one or other party3;


    (3)     where, although there is a mistake against which the court would in principle relieve by rescission or rectification4, a third party has acquired legal or (possibly) equitable rights in the subject matter of the