There are unfortunately no standards for art authenticity within the art market. Some insurance companies require an appraisal. Some insurance companies require authenticity. Some insurance companies require neither. Some insurance companies require both.
None have a standard regarding degree of authenticity or accepted experts.
When it comes to establishing value, some accept invoices, some accept appraisals by dealers, and some require independent appraisals. In litigation, regarding Fine Art, whether it s divorce, probate, fraud, etc. It is usually non-scientific and therefore one person s opinion against another. Most attorneys do not even know what questions to ask in this specialized field, in order to arrive at precedent standards. Another example of the lack of understanding of the problem outside the art world is an action taken by the U.S. Attorney s office in a case involving fraudulent art.