It must be appreciated that the ‘cold calculus’ of the doctrine of notice applies in the sphere of proprietary liability so as to protect property interests: equitable interests bind everyone but a bona fide purchaser of a legal interest without themself or their agent having actual or constructive notice (the agent’s notice being the imputed notice of his principal). If you have notice you have to return the property that should not have been your property, or if you received the property as a gift you have to return the property that should not have been your property.