Identifying Autopens : Autopen Traits
2.1 Abrupt pen stops
At the end of each stroke the autopen machine stops then lifts the pen straight up. This does not happen instantaneously and with certain types of pen this pause leaves a characteristic 'blob' of ink at the end of each line which is rare in a real signature.
When drawn by hand the end of a pen stroke will tend to lift up smoothly from the page, leaving a tapering mark and no ink blob. It's important to realise however that even real signatures sometimes have blobs of ink at the end of certain strokes, as shown in the John Young example below. With an autopenned signature however, the end of every stroke tends to be abrupt.
This genuine John Young signature shows an ink 'blob' at the end of the "John", but the tapering stroke at the end of the "Young" is typical of a genuine signature.
A Gene Cernan autopen with characteristic abrupt pen stops and ink 'blobs' at the end of each stroke