With regards to analyzing a signature, on a check or on anything really, there are a multitude of options that can be utilized to determine authenticity. 3 examples are:
1. Analysts can look at the type of ink used to create the alleged signature. The composition of commercial ink pens tend to be very similar, but if someone attempted to print a signature using a computer printer, the composition would be quite different. Chromatographic analysis could be done on the signature to determine the true identity of the various components.
2. Analysts will often look at the flow rate of ink throughout the signature. Natural signatures have a varying degree of pressure from the writer that creates different flow rates throughout the signature. Often when someone attempts to copy a signature, they are very deliberate with the motions creating a uniform flow rate throughout the signature.
3. Analysts can compare the signature to an authentic marker from the alleged signer. Individuals have unique characteristics with regards to their handwriting. For example, when write a word like 'together', analysts focus their attention on the 'th' region of the signature. Individuals tend to fall in three categories when they write the letters t and h next to one another: those that have a taller t than h, those with a taller h than a t, and those whose letters are equally tall.