A residential lease is, when it is signed, the document by which a particular dwelling becomes the principal's address for a period of time. It is, in most jurisdictions, a private contract between the parties. The expectation, when it is signed, is that its life ends when the tenancy ends.

Several practices give the lease a longer life than the tenancy. It is held by the landlord, who has reasons to retain it. It is held by the letting agent, whose retention practices vary. It is held by a managing agent for the building, whose systems may outlive the original parties. It may be referenced in tax records, in insurance records, in the management accounts of a building, in the dispute records of a small tribunal. None of these is, on its face, public; several are not as private as the original parties expect.

The detail captured by a lease can be unusually rich. The principal's identity at a particular date. The address at that date. The financial position implied by the rent. The household composition where it was disclosed. The guarantor, where one was required. The address of the previous tenancy, where it was given as a reference.

The exposures here are usually not dramatic. They are precise. A lease that has reached an aggregator from a leaked agent's file, an old letting platform, or a court matter in which the document featured, becomes a dated and signed record of where the principal was, in what arrangement, and on what terms. It is rarely the most prominent record about a principal; it is often one of the most accurate.

The remediation here is patient. The original document cannot be unwound. What can be done is the careful audit of which leases the principal has signed, which of them may have travelled beyond the original parties, and what the assembled picture they produce now says about a residential history the principal would otherwise have considered settled.