Letter of Authenticity
It may be signed by the artist, but it may also be issued by artists’ legal representatives. If the artist dies, then his or her legal successors are usually the ones issuing certificates. However, once a certificate is in hands of a collector, he or she then becomes a legal possessor, and it may be sold to a third party.
The certificate of authenticity for artwork is also a tool in determining an artwork’s provenance, with the certificate declaring that the work is indeed created by an artist. Giving a buyer a COA is a way to indicate that the work they are buying is worth the investment