13 Pa.C.S. § 3413 – Obligation of acceptor

(a) General rule.— The acceptor of a draft is obliged to pay the draft:
1. (1) according to its terms at the time it was accepted, even though the acceptance states that the draft is payable "as originally drawn" or equivalent terms;
2. (2) if the acceptance varies the terms of the draft, according to the terms of the draft as varied; or
3. (3) if the acceptance is of a draft that is an incomplete instrument, according to its terms when completed, to the extent stated in sections 3115 (relating to incomplete instrument) and 3407 (relating to alteration).
  The obligation is owed to a person entitled to enforce the draft or to the drawer or an indorser who paid the draft under section 3414 (relating to obligation of drawer) or 3415 (relating to obligation of indorser).
(b) Certified check or accepted draft.— If the certification of a check or other acceptance of a draft states the amount certified or accepted, the obligation of the acceptor is that amount. If the certification or acceptance does not state an amount, the amount of the instrument is subsequently raised and the instrument is then negotiated to a holder in due course, the obligation of the acceptor is the amount of the instrument at the time it was taken by the holder in due course.