A Disclosure Letter is a method of limiting / qualifying the warranties made by the seller. If a disclosure is made against a warranty then it means that the buyer will generally (subject to whether disclosure was sufficiently full and accurate etc) not have a claim under the particular warranty in question.

The Disclosure Letter will contain general disclosures that the seller would expect the buyer to be aware of / find out for itself, for example, information available to the public such as that at Companies House.

The other type of disclosures are specific disclosures that will be made against specific warranties. However, because of the overlap, the disclosure letter often states that the specific disclosures apply against all of the warranties, rather than just specific warranty X, Y or Z.