Regardless of how a museum shares information about provenance, the most important goal is to be as forthcoming and accurate as possible. To that end, documenting an object’s provenance may involve not just tracing its history of ownership (what do we know?), but also recording the sources of that information (how do we know it?), and noting the differences between verified and unverified data. Information about provenance can come from verbal statements, circumstantial evidence, or attestations provided by a seller or donor that have not been (and often cannot be) corroborated. Museum records should reflect these uncertainties and any vague or hypothetical statements.
The looting and illicit export of art treasures is not a new problem. It’s happened whenever there have been armed conflicts during which victorious troops plundered churches, temples and other buildings. Germany carried out massive looting in World War II. By the start of the 21st Century the trade in illicit antiquities had become so huge it was worth billions of dollars each year and was the biggest international crime outside drug and arms trafficking according to The New York Times. When a piece is stolen, the consequence for scholars is tragic, because essential information about the piece – where it was found, what else was with it – is lost forever.