56. Indorsement for part of sum due. —No writing on a negotiable instrument is valid for the purpose of negotiation if such writing purports to transfer only a part of the amount appearing to be due on the instrument; but where such amount has been partly paid, a note to that effect may be indorsed on the instrument, which may then be negotiated for the balance.
Section 56 NI Act — Indorsement for part of sum due
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