Negotiable Instruments Act Section 45 — Partial failure of consideration not consisting of money
CHAPTER III PARTIES TO NOTES, BILLS AND CHEQUES.
General
Summary
If someone signs a promissory note, bill of exchange, or cheque as payment for something that is not money—like goods or services—and only part of that payment fails, the amount they owe is reduced in proportion to the failed part. This reduction applies only if the value of the failed part can be figured out in money without needing any outside investigation. Also, this rule only helps a holder who is directly connected to the person who signed the instrument, not someone who later receives it.
Official Text
Where a part of the consideration for which a person signed a promissory note, bill of exchange or cheque, though not consisting of money, is ascertainable in money without collateral enquiry, and there has been a failure of that part, the sum which a holder standing in immediate relation with such signer is entitled to receive from him is proportionally reduced.