Negotiable Instruments Law
Section 124. Alteration of instrument; effect of.- Where a instrument is materially altered without the assent of all parties liable thereon, it is avoided, except as against a party who has himself made, authorized, or assented to the alteration, and subsequent indorsers.
But when an instrument has been materially altered and is in the hands of a holder in due course, not a party to the alteration, he may enforce payment thereof according to its original tenor.