A more thorough explanation:

The doctrine of notice is an equitable principle that applies when a new owner acquires an estate with knowledge that someone else had a claim on it at the time of the transfer. In such cases, the claim may still be asserted against the new owner, even if it might have been disregarded at law.

For example, suppose that John sells a piece of land to Jane, but John had previously promised to sell the same land to Tom. If Jane knew about Tom's claim when she bought the land from John, the doctrine of notice would prevent her from ignoring Tom's claim and taking ownership of the land.

The doctrine of notice is designed to prevent fraud and unfairness in property transactions. It ensures that buyers cannot simply ignore existing claims on a property and take ownership without addressing those claims.