Wiktionary
chain of title
n. (context legal English) In the law of real property, a series of documents recorded in the appropriate government repository which establish the passage of a parcel of property from owner to owner, ideally back to the first owner to reduce the property to private ownership.
Wikipedia
Chain of title
A chain of title is the sequence of historical transfers of title to a property. The "chain" runs from the present owner back to the original owner of the property. In situations where documentation of ownership is important, it is often necessary to reconstruct the chain of title. To facilitate this, a record of title documents may be maintained by a registry office or civil law notary.