Imagine encountering a painting of extraordinary merit—one that captivates your interest and is offered at an enticing reserve price. The auction catalog presents it as an antique work from the correct historical period, and you are prepared to bid. Yet, a lingering doubt arises: what if the piece is, in fact, a later copy?
This concern is far from baseless. In the art market, the distinction between an authentic masterpiece and a high-quality copy—no matter how skillfully executed—can represent the difference between a valuation in the millions and one in the mere tens of thousands.
Surprisingly, auction houses are under no legal obligation to conduct scientific analyses before naming a particular artist in relation to a painting. Each piece is presented to the public with the information at hand, yet without absolute guarantees of authenticity. For instance, Farsettiarte (Italy) explicitly states in its terms of sale: “The buyer is responsible for satisfying himself as to the condition of the lot and the matters relating to its description, including but not limited to its authorship, attribution, genuineness, origin, date, age, provenance, and condition.”
Thus, even when the catalog proposes an attribution, the onus falls upon the buyer to verify the condition and all pertinent details of the lot—authenticity, provenance, dating, and so forth.
This means that, in the absence of diagnostic evidence, an auction house may attribute a work to an artist based on historical, stylistic, or expert opinion alone, without the need for scientific validation. Consequently, the buyer must place trust in the auction house’s reputation, the validity of any existing catalogues raisonnés, and, where applicable, the assessments of esteemed scholars—though such opinions are not immutable and may evolve over time.
In certain cases, auction houses choose to include the results of diagnostic investigations—such as X-rays, infrared reflectography, pigment analysis, or carbon-14 dating—in the catalog. Should an X-ray reveal a preparatory sketch consistent with a particular artist’s technique, or if pigment analysis confirms the use of materials characteristic of a specific period and master, such findings are often emphasized to bolster the work’s credibility and enhance its value.
Conversely, if the investigations fail to confirm—or worse, contradict—the proposed attribution, it is not uncommon for such data to be omitted from the catalog. By doing so, the auction house avoids undermining the confidence of potential buyers and preserves the commercial narrative surrounding the piece.
A case in point is the “Portrait of a Man,” attributed to Rembrandt and sold by Sotheby’s in 2020 for €11.5 million. Sotheby’s presented the painting as an authentic Rembrandt, supporting the attribution with X-ray analysis and pigment studies that aligned with the Dutch master’s known techniques and materials. In this instance, the findings were explicitly highlighted in the catalog to reinforce the work’s legitimacy.
Nevertheless, there have been instances where subsequent scientific analyses have prompted the reclassification of works initially marketed as autograph, downgrading them to categories such as “workshop of,” “school of,” or “attributed to.”
For collectors, this presents a dilemma: should they place their trust in auction houses, accepting that attributions are often based on subjective judgment and the seller’s standing, or should they insist on independent analyses prior to acquisition? The most prudent collectors resolve this by requesting access to all available investigations and, when in doubt, commissioning their own independent assessments. Art-Test, for example, offers a tailored solution with a suite of rapid and accessible diagnostic services.
For auction houses, the challenge lies in striking a delicate balance between transparency and commercial strategy in a market where trust remains the most precious currency.
