Many works offered on the market come with a document that the seller describes as a certificate of authenticity, whether a letter, a photograph signed on the reverse, a confirmation of inclusion in an archive, which records a notification and not always a judgement, or an extract from a catalogue. One of the costliest mistakes a collector can make is to treat such a document as a definitive guarantee and not to carry out the appropriate checks. A certificate expresses a written opinion formulated by a particular person, and it is therefore essential to establish who that person is and whether the document itself is genuine.
First level: who signed it
The first level of analysis concerns the author of the statement. An opinion on attribution carries weight if it comes from those qualified to formulate it: the scholars who specialise in the artist, the archive or foundation, where they work with method and evidence, committees and, within the limits of their competence, the heirs; for living artists, the artist in person. Qualifications are recognised by published studies on the artist, by the recognition of peers and by the absence of any interest in the sale. In Italy there is no official certifier and no public body responsible for authenticating works of art, so that anyone may set up an archive or sign a declaration, and even the opinion of an archive remains an opinion to be verified. What matters is not the existence of a certificate but the authority of its issuer. A document signed by someone without scholarly knowledge of that artist's work (a non-specialist critic or an unidentifiable figure) offers little of substance; a restorer's opinion is valid for materials and condition, not for attribution; the opinion of whoever is selling the work is given under a conflict of interest.
Second level: is the document genuine?
The second level of analysis verifies the genuineness of the document itself. Paper documents are frequently forged: a letterhead, a forged signature or a stamp is all it takes. Verification requires direct contact with the archive or foundation and a request for formal confirmation that the work in question was in fact registered on the date indicated. Serious archives keep a copy of the opinions they have issued and do not reissue duplicates: a copy is to be checked against their register. A sound opinion contains a precise description of the work, photographs, a statement of whether the work was examined in person or from a photograph, the evidence and reasoning on which it rests, any reservations, a date and an identifiable signature, whereas a generic document or one without images carries very little weight.
Third level: does the document match the work?
The third level of analysis establishes that the documentation corresponds exactly to the physical object. Dimensions, technique, inscriptions and markings on the reverse must match the description precisely. There are cases in which a genuine document was originally issued for a different work.
The seller's attestation is something else
A frequent confusion also needs clearing up. Under Italian law, those who trade professionally in works of art are required to provide the buyer with an attestation stating the attribution and provenance of the work, or a declaration containing the information available. It is a required and useful formality, and its absence is a warning sign. It is, however, a commercial declaration made by the seller, summarising what the seller knows, and it is not equivalent to an opinion on authenticity formulated by an artist's archive or a specialist.
A certificate does not close the due diligence
Finally, the existence of a certificate does not exhaust due diligence. Several international archives no longer issue written opinions, scholarly attributions evolve as research progresses, and works historically accompanied by documentation or shown in exhibitions have at times proved not to be by the artist. The certificate is one of the documents to be examined within an overall analysis, together with the opinion of the scholars, the archive or the heirs, the consultation of every existing catalogue raisonné, the reconstruction of provenance and any scientific analysis; every opinion gathered is to be recorded, even where it differs from the others. The appraiser and the art advisor do not issue certificates of authenticity; they verify them rigorously before proceeding with a valuation or recommending a purchase.