Negotiable Instruments Law

An alteration is said to be material if it alters the effect of the instrument. It means an unauthorized change in an instrument that purports to modify in any respect the obligation of a party or an unauthorized addition of words or numbers or other change to an incomplete instrument relating to the obligation of a party. In other words, a material alteration is one which changes the items which are required to be stated under Section 1 of the Negotiable Instrument Law.