The IADA is a new foundation for art market certification. Membership in the IADA is awarded to dealers whose IADA rating is above a certain threshold. This IADA rating is an automatically calculated, composite score of the dealer's user reviews and provenance rating.

Worse Provenance

Ex. old American collection

Better Provenance

Ex. Smith's Collection, New Jersey, USA

Great Provenance

Ex. Dr. Smith's collection, purchased in 1990 from East Coast Antiques, New Jersey, USA; from thence by descent.

Best Provenance

Ex. Dr. John Smith's collection, purchased in 1990 from East Coast Antiques, New Jersey, USA; from thence by descent. Ex. Galerie Friesen, Berlin, Germany. Originally found in Locri, Southern Italy in 1982.