---
id: KB-CO-018
url: https://app.codecontract.io/help/consigne/if-someone-denies-having-signed
idioma: en
categoria: consigne
subcategoria: prueba
audiencia: usuario
nivel: avanzado
actualizado: 2026-08-13
tambienEn: [es]
relacionados: [KB-CO-004, KB-CO-009]
citadoPor: [KB-CO-020]
---

# If someone denies having signed

_What holds an electronic signature up is not the signature: it is everything recorded around it._

**Responde a:** a client says they did not sign · challenging an electronic signature · how do I prove that person signed · what if they deny the signature

It is rare, and when it happens it is usually months later and over something else: someone disputes an invoice, an order or a term, and along the way says they never signed that document. The question then is not whether the signature is valid in the abstract, but what you can show.

## What you show, and what each piece proves

| What was recorded | What it proves | What it does not prove |
| --- | --- | --- |
| The document and its fingerprint | That it has not been altered since | Who signed it |
| The exact moment, timestamped | When it happened, without relying on your clock | That the person agreed |
| The address or number it went to | Who it was aimed at | That this person, and not another, read it |
| The one-time code, if used | That whoever signed had access to that mailbox or phone | The person's legal identity |
| The trail: sent, opened, signed | That there was a voluntary act, with its trace | The intention behind it |

> [!IMPORTANT]
> No single row of that table proves everything on its own, and that is the part almost nobody expects: **what convinces is the whole set**. An electronic signature is not defended by showing «the signature», but by showing the full sequence — who it went to, where it was opened from, which code was used, when, and over which exact document. That is why sending documents around by hand on the side matters so much: the missing piece is always the one they ask about.

## What to do when the denial arrives

1. **Redo nothing** — Do not resend, do not re-sign «to have it cleaner». That muddies what you already hold.
2. **Download the complete set as it stands** — Document, evidence and timestamp, unedited and unassembled.
3. **Cross-check against what sits outside** — Emails, orders, deliveries: they nearly always back the same version.
4. **And pass it to your adviser before replying** — The legal answer shapes what you say from the first line.

> [!WARNING]
> The commonest case is not bad faith: it is **that someone else with access to the mailbox signed** — a colleague, someone in admin, whoever runs the generic address. It is usually true and usually irrelevant to validity, but it changes the conversation. If the document matters, send it to a named person rather than to `info@`, and require a code; not out of distrust, but so there is something to show afterwards.

## What raises the bar before it happens

**En corto**

- Send to a person's name and address, not to a shared mailbox.
- Require a one-time code on anything with consequences.
- And use a qualified signature when the document warrants it: it changes who has to prove what.

> [!NOTE]
> Which signature level suits each document, and how it is weighed in proceedings, depends on the framework that applies to you — **eIDAS** in Europe, among others — and on the type of contract. **Your adviser decides that**; here we explain what is worth keeping so that decision does not arrive too late.

**Is it worth less for being electronic?**

That is not the question: what counts is the evidence around it.

**What if it was signed five years ago?**

It still works if you kept it complete; the timestamp is what fixes the «when».

**Can I add evidence now?**

No: anything produced today is dated today, and it shows.

## Ejemplos

**A client disputes an order and says they never signed the acceptance note.**

- Downloads the complete set untouched and passes it to their adviser

→ The sequence shows who it went to, where it was opened from and which code signed it.

**The signer says they never received the document.**

- Checks the send and open evidence

→ It is on record when it was delivered and where it was opened.

**They say somebody else signed for them.**

- Checks the code sent and the device

→ The signature points to a device and a time.

**Only the PDF is provided, without the evidence.**

- Provides the document with its complete chain

→ The defence does not rest on an assertion.

**The file was re-saved and no longer validates.**

- Keeps the original exactly as signed

→ Verification still works.

**A third party is asked to check it.**

- Points them to the verification page

→ They check without intermediaries.