There is no direct English authority on this but it was raised as an issue in
the following American case.
So if, in the case of Carlill v Carbolic Smoke Ball Company the Company
had wanted to revoke their offer, they would simply have needed to place
notices in the newspapers in which they had previously advertised the offer,
saying that it was now withdrawn.
Revocation during an ongoing act of acceptance
Problems may occur when an offeror attempts to withdraw an offer while a
person is in the process of accepting (remember, accepting is often by
conduct in unilateral contracts). An example of the problem is found in the
following case.
Offer and acceptance 19
Shuey v US (1875)
The case concerned a reward for the apprehension of a criminal. The
plaintiff was not given the reward because he had not actually
‘apprehended’ the criminal, but it was also said that the notice had been
revoked because ‘the same notoriety was given to the revocation that
was given to the offer’.
Figure 2.3
How many promotional offers have you seen recently? Have you ever seen
a revocation of a unilateral contract? Do you think that this law actually
operates in practice, or do members of the public assume that if a notice is
no longer on display the offer it contained has ended?
Errington v Errington (1952)
A father bought a house on mortgage, and promised that if his son
and daughter-in-law paid all of the mortgage instalments, the house
would be theirs. The couple paid the instalments, but when the father
died his widow tried to obtain possession of the house. She was