Collecting histories lie at the heart of research behind objects that surface on the market. Can the 'history' be traced back to a point before the 1970 UNESCO Convention (or the relevant law relating to cultural property from a particular country)?
We should not mistake oral accounts for history. Phrases such as "said to be from an old collection" or "thought to have been in a specific collection" need to be checked out by those selling objects at auction or in a gallery, and certainly by those acquiring the items. What is the authenticated documentation? (Note, not just the documentation.)
The Ka-Nefer-Nefer mummy mask excavated at Saqqara and now in the St Louis Art Museum has a reported collecting history that does not sit comfortably with other verifiable evidence.
In 2016 the issue of the due diligence process needs to be brought higher up the agenda so that buyers need not be concerned that they are acquiring objects that could be contested in the courts or reclaimed by national governments.