Document Forgery: This involves the creation or alteration of documents such as contracts, wills, deeds, or financial instruments. Signature forgery involves unauthorized imitation or alteration of a person's signature on documents, checks, or other legal instruments.Simulation- attempt to copy a signature or handwriting sample ii. There are 3 forgery crimes in New York. Forgery crimes are classified as both felonies and misdemeanors in Pennsylvania, depending on the type of document or instrument involved. In general, forgery would either be with the intent to defraud or the false creation or an alteration of a writing.