Judicial principles and studies
Blank-Signed Instruments in Ordinary Written Notes and Their Evidentiary Effect
A brief summary of issues relating to signatures on blank written instruments, admissibility of personal testimony, and how added or altered entries affect the instrument's probative value.
Updated: 10 September 2026
Prepared and reviewed by: Ashraf Al-Khawaja
Subject
- A signature manifests the signatory's intent to be bound and typically crowns what was recorded. - Under the framework cited (Articles 10/11), an ordinary written instrument goes through three stages: formation of intent, recording of the agreement, and signing; a signature on a blank leaves the obligation's object undefined and may create such uncertainty that the instrument lacks a valid subject matter.
Summary
- A debtor who signed a blank instrument may contend that later-entered entries contradict the original agreement and may prove that fact by all lawful means provided the signer does not deny the signature. - The circumstances surrounding the drafting of the instrument are material facts; personal testimony can be admitted to prove a blank signature under the rules reflected in Article (30/5) and Article (27). - If entries are added after signing but remain within the scope of the original agreement and there is no abusive use of the blank signature, the instrument may acquire full probative force and the earlier signature will be treated as if it were a subsequent one. - If it is shown that the signature was exploited by adding or omitting amounts contrary to the agreement, the instrument loses its evidentiary value against the signer for lack of the writing requirement; thus, refusing to hear personal testimony in such a case would be premature and contrary to the law. - Establishing exploitation of the signature and mismatch between recorded entries and the true agreement are material facts and do not require technical expert examination.
Practical significance
- Parties should ensure the obligation's subject is specified before signing to preserve evidentiary effect. - Allowing personal testimony on blank-signature claims strengthens the signer’s defenses. - Additions within agreed limits do not necessarily impair probative force; abusive alterations negate the instrument’s effect against the signer. Note: This is an educational summary based on the provided official points. It is not a judicial text or legal advice and does not represent any court or legal office.
Sources and references
Verify the official text and latest amendments before relying on this material professionally.