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+44 (0)1534 639998 | info@justcollecting.com
+44 (0)1534 639998 | info@justcollecting.com

How we authenticate an autograph

We have been authenticating autographs since 1977, making us one of the world’s foremost authorities today.

Over the past 40+ years we have compiled an extensive reference library of known genuine autograph examples to assist us in authentication. 

Here’s our 20-step process to authenticating a signature:

  1. Always research the example under ultra-violet light, microscope and magnifying glass. In extreme cases, use chemical testing
  2. Talk to the seller and find out any known history or provenance that comes with the piece
  3. Date the item to within the signer’s lifetime
  4. Ensure that the paper, ink and method are typical of the date
  5. Check that the style of signature is contemporary to the period stated
  6. View the size and position of the letters. Most people maintain the same size, position and angle throughout their lives
  7. Inspect the proportions of the letters. Even where signatures vary in size, it is still normal for all the individual letters to be in proportion
  8. Examine the idiosyncrasies of the writer and the scope and style of the individual characters
  9. Consider the flow of the signature or writing. Forgers often keep the pen on the page after the stroke, which creates a dot or blob of ink, where it would be more normal to lift for a lighter finish. Sometimes it is better to look at the document upside down, as it is easier to see a different flow
  10. Ensure that the flow of the pen is uninterrupted, with varying degrees of heavy and light pressure and thickness of strokes
  11. Check for abnormal absorption of ink. Also, India ink has a sheen, printing ink does not
  12. Be wary of a feathery spread of ink – typical of when a signature is not contemporary with the medium
  13. Check for secretarial or proxy signatures, usually either written slowly and displaying too much attention to detail of individual characters, or too fast with the opposite effect
  14. Be on alert for Autopen signatures, which normally produce a squiggle, as the machine finds straight lines difficult
  15. Look out for distinct national characteristics, such as French script
  16. Check for stamped signatures, which display ink shading around characters where the ink on the pad has transferred to the paper
  17. Scrutinise for signs of tracing. A traced item is usually shaky or sometimes there are pencil marks or indentations under the ink
  18. If the content is superb, then it warrants even further scrutiny due to its increased potential value
  19. Recognise that the signature is of more value if considered to be signed at the height of their career, or most important point in their life
  20. Forgers ultimately make mistakes with content, dates, the medium used, or the general spirit of the piece

Key dates

  • It was not until the 15th Century that accomplished people started to sign their own name
  • Different paper existed pre-1750. Wove paper without grid pattern (visible when held up to the light) was post-1750
  • Steel pens were introduced in 1780
  • Water soluble ink came in to use in 1860
  • Autopen machines were introduced in the 1950s
  • Biro arrived during WWII to enable pilots to write upside down if necessary and in the air rather than on a surface
  • Felt tip pens came in just after WWII
  • Watermarks in paper sometimes contain dates

And lastly

Please start from the premise that the item is probably wrong, and then prove that it is right. Otherwise the "will to believe" will take over. If the item is too good to be true it probably is.