Arts & Culture:
So now you might want to know - what is the difference in value between a signed and unsigned painting by an artist? Initially, it is important to know if the artist normally signed his works. If so, and you have your choice between two similar works (one signed and one unsigned) I would recommend buying the signed one - there will be less issues to deal with when you decide to resell it.
Of course, there are instances when an artist, who normally signed their paintings, did not sign a work. I know ...why? Sometimes these works were not for sale while the artist was alive, remaining in their studio or personal collection; or the buyer requested that a signature not be added; or the artist just forgot to sign it (yes that does happen). Any unsigned works that were sold during the artist's lifetime should always remain unsigned - in other words, you should not have someone add a signature. An added signature can be detected and it will create doubt about its authenticity when it reappears on the market. You may also find that historical records will surface indicating that the painting was not signed.
Now any unsigned works that were part of an artist's estate may have the benefit of an "estate stamp" (a stamp of the artist's signature created by those handling the estate). The individuals handling the estate would then stamp all of the works before they are sold and destroy the stamp so it could not be used by someone in the future. As long as the estate was handled professionally, there should be no issues with these works and their values will be comparable to those works which have the artist's signature on them. Rosa Bonheur, the 19th century French artist, is a good case in point. After her death a large "studio" sale took place and all the unsigned works were estate stamped. In addition, a rather lavishly illustrated catalogue was produced... making it much easier to determine if a specific work was part of the studio sale. Over the years, many of her "stamped" works have reappeared on the market and they continue to bring strong prices.
Then there were artists who rarely signed their works. In these cases, authenticity is based on expert opinion and/or detailed documentation. One of the crucial elements in determining the work's authenticity, other than its quality, is provenance (chain of ownership). The more complete the provenance, the easier it is to track the painting's history...at times, leading you right back to the artist and/or their dealer. Generally, unsigned works are more frequently seen in the Old Master period and that is why attributions to specific artists change over time. However, attributions are becoming more definitive as additional scholarly research is conducted and more sophisticated scientific tests are being developed.
Keep in mind that many Old Master paintings are unsigned and the important documented works can sell for millions of dollars. Even those 19th century paintings that may not have a signature can command premium prices if the art world believes the work to be authentic ... we saw this when an unsigned work by Antonio Jacobsen, titled Fetching the Mark, came on the market. It is rare to see an unsigned painting by Jacobsen, but they do exist, and in this case all the experts agreed that the work was by the artist and it brought a record price of $281,000.
Finally, does the reputation of the expert have some influence on this? Yes. Those experts who are both knowledgeable and viewed as impartial when it comes to their opinion are held in the highest regard. If they say a work is by the artist in question, then the art world has little doubt about the work's authenticity... many times, their stamp of approval is all the buyer and seller need. However, those "experts" who are not well respected, or even acknowledged as the "true" expert, will still leave the unsigned works in limbo... and the price will reflect this continued uncertainty.
Howard L. Rehs
Rehs Galleries, Inc., New York City