7 important things to know about artist signatures

Artist signatures first became prevalent during the early Renaissance, which saw art production shift from co-operative guild systems to a celebration of individual creativity. A signature was the perfect way to differentiate your talent from that of lesser peers.

In the case of Albrecht Dürer, whose famed monogram featured prominently on everything from printed masterpieces to hurried sketches, his ‘AD’ trademark (above) was so popular that he went to court in both Nuremberg and Venice in a successful bid to protect his authorship, resulting in the subsequent proliferation of copycat prints labelled ‘after Dürer’.

‘I’ve worked with artists who use signatures as a note to themselves,’ says Sid Motion, who works with emerging contemporary artists at her eponymous gallery. ‘It’s a way of saying, “That piece is complete, don’t rework it”. It’s an honest, personal mark that stops them endlessly returning to a piece.’

Signatures are also commonly used to keep a record of time, place and medium, as much as they are a signifier of a completed work. ‘Ben Nicholson recorded a wealth of information on the back of his boards,’ says Rachel Hidderley, Christie’s Senior Director of Modern British and Irish Art. ‘He not only signed, titled and dated his work, but sometimes even listed the colours he used, or the address of where he would be sending the work on to.’

‘There’s no end to the variety of signatures an individual might use,’ according to John Castagno, an artist and renowned expert who has produced 17 reference books cataloguing artist signatures throughout history, as well as offering a full consultation service to museums, galleries and collectors.

‘My first volume contained more than 10,000 entries,’ he explains, ‘with many artists using symbols and variations on their name. James McNeill Whistler had many different styles [he was well known for his use of a butterfly motif not only in his art, but also in his personal correspondence]. In other cases marks are almost completely illegible, such as those of Jean-Michel Basquiat. He had two script signatures that were virtually impossible to read, along with his printed version.’

Although these variations might seem confusing, they can actually be very useful when it comes to dating a work. ‘Picasso is a great example,’ says Christie’s Impressionist and Modern Art specialist Allegra Bettini. ‘In his early career he signed including his middle name as P R (or Ruiz) Picasso, later dropping the initial and developing a more decorative version. 

‘During his analytical Cubist period he stopped signing the fronts of his canvases entirely in order not to detract from the art itself, whereas later on he adopted his famous signature, complete with an underlining dash. This was also used as a symbol of completion.’

Uncovering hidden signatures can reveal a wealth of information lost during the passage of time. In 2015, Christie’s Australian Art department discovered a hidden signature and inscription by the Australian Impressionist Tom Roberts.

‘When studying the portrait of Louis Abraham there was no visible signature,’ recalls Head of Sale Amanda Fuller. ‘But as we moved the work around under the light, something caught our eye. We had the work photographed and asked our digital studio to enhance the image, and in doing so they were able to reveal a dedication from the artist to the sitter, signed and dated, in the background. It was a great moment, as this confirmed our suspicion that the work was indeed painted by Tom Roberts.’

An even more unusual case is that of a drawing by Gabriel-Jacques de Saint-Aubin, whose portrait of King Louis XVI was mistakenly considered to depict a woman, until about 2002. ‘Funnily enough, when I was cataloguing this work a few weeks ago I actually realised that “Louis Auguste” was written in reverse at the ledge,’ says Associate Specialist Jonathan den Otter. ‘It looks as though no one had noticed this in the past 250 years! It’s written in the artist’s typical handwriting, and so it proves both the attribution and the identity of the sitter.’

Although signatures can confirm well-founded research, they can also be misleading. An upcoming lot in The Former Kamerbeek Collection sale briefly featured a spurious autograph by Bernardus Johannes Blommers, hiding the true identity of its creator, the Dutch painter Jozef Israëls.

The painting was probably doctored during the Second World War in order to obscure the fact that the artist was Jewish, and to save his work from being confiscated or destroyed. After its provenance was questioned in 2003 the real signature was uncovered in the bottom right-hand side of the piece, and the false version was removed.

‘Added signatures are a key issue on the market,’ says Tom Rooth, Director of the Victorian & British Impressionist Pictures Department at Christie’s. ‘They tend to fall into one of two camps. Either a painting has been created to imitate an artist’s work, together with a mimicked signature, or someone might add a signature to a picture at a later date, in order to deceive, and increase value — sometimes significantly. 

‘It is generally fairly easy to detect both,’ Rooth explains. ‘There is often a concentration in execution, and a slower, more deliberate manner is apparent that you wouldn’t expect from someone signing their own name; faked signatures often lack fluidity. After seeing numerous works signed by an artist, you also develop a familiarity with how they sign and inscribe. Of course you can also put the painting under a UV light. If the signature has been added at a later date, the difference in pigment will show up by flaring.’  

Rooth also looks out for artists who might have minimal signatures. ‘Myles Birket Foster was an exceptional watercolourist, but his monogram was very simple. This has made him attractive to forgers who think they can replicate the simple ‘BF’ — although imitating the exceptional hand and brushstrokes of a maestro is significantly harder to get away with, to say the least.’

When considering whether to invest in a work of art it is important to know whether an artist normally autographs their work. ‘If you have the choice it is always wise to favour signed over unsigned examples,’ advises Rachel Hidderley. ‘However it is crucial to remember that some artists — such as Stanley Spencer or Christopher Wood — never signed anything. So it pays to remember that sometimes you won’t find a signature at all, and nor would you want to.’

In research terms a signature is always one piece in a larger puzzle. ‘When we first see a work of art, of course the inscription is something we will take into consideration,’ says Angelica Pediconi, a fine art conservator and art historian who has worked with international dealers, collectors and institutions including the National Gallery. ‘Often something might be obscured due to oxidation, so if we uncover anything we are careful to examine it under a microscope.

‘You have to look at the craquelure [the network of cracks that develops as paint layers age and shrink] to see if it matches the panel or canvas,’ she continues, ‘or work out whether it has been retouched. When we make a discovery we are careful to transcribe our findings and consult with the owner. However, signatures are just one part of what we look for in our research. Everything you need is in the painting itself — you just need the eye.’