# Registering the alias without an electronic certificate

If the alias owner or their legal representative has no electronic certificate valid in Spain, they can designate another person or entity through an authorisation letter. How it works, who signs it, and how it's used in the Sender Alias Registry.

**Language:** en
**Audience:** platform
**TLDR:** Registering an alias means acting electronically at the CNMC's electronic office with a certificate valid in Spain. If the owner or their legal representative doesn't have one, they sign an authorisation letter designating a person or entity that does hold a valid certificate to act on their behalf. There are 7 letter templates depending on the owner (natural person, legal entity, foreign, public administration). It's signed by the owner or their legal representative —and also by the authorised representative—, then attached in the Sender Alias Registry by choosing «En representación de» (on behalf of), ticking «Autorizado» (authorised) and uploading the letter.
**Translation key:** platform.channels.countries.spain.authorization-letters
**Search keywords:** cnmc, authorisation letter, authorization letter, authorisation letters, without a certificate, without an electronic certificate, certificate valid in spain, authorised representative, authorized representative, autorizado, alias registration, inscripción de alias, letter template, natural person, legal entity, public administration, foreign company, foreign natural person, llc, signature, who signs the letter, en representación de, on behalf of, attach letter, spain
**Related pages:** /platform/en/channels/countries/spain, /platform/en/channels/countries/spain/authorize, /platform/en/channels/countries/spain/self-register, /platform/en/channels/countries/spain/rejected, /platform/en/channels/sms/senders-registration, /platform/en/channels/rcs/senders-verification, /platform/es/channels/countries/spain/authorization-letters
**Docs index (every page):** https://docs.instasent.com/llms.txt
**This zone's index:** https://docs.instasent.com/platform/en/llms.txt
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**Other language (es):** https://docs.instasent.com/platform/es/channels/countries/spain/authorization-letters.md

To register an alias with the CNMC, someone has to be able to act electronically
before its electronic office through a **certificate valid in Spain**. If the alias
owner or their legal representative has no such certificate, they can designate
another person or entity as an **authorised representative** through an
**authorisation letter**.

This way, the owner's legal representative doesn't need to obtain a Spanish
certificate: it's enough to sign the letter and authorise a person or entity that
does hold an electronic certificate valid to act before the Spanish public
administrations.

## Types of authorisation letter

There's a different letter template depending on who the owner is. Each form shows
the details to fill in and the responsible declarations that apply to the process:

- **Spanish natural person or one legally resident in Spain**
- **Spanish legal entity**
- **Public Administration**
- **Foreign natural person**
- **Foreign natural person ESP-EN** (with a section to complete in English)
- **Foreign legal entity**
- **Foreign legal entity ESP-EN** (with a section to complete in English)

## Who must sign the authorisation letter?

It depends on who the alias owner is:

- If the owner is a **natural person or a self-employed worker**, the letter must
  be signed by the owner themselves.
- If the owner is a **company**, the letter must be signed by its legal
  representative or a person with sufficient authority to act on behalf of the
  company.
- If the owner is a **foreign company**, the letter must be signed by a natural
  person with the authority to legally represent the company under the laws of
  their country.

The letter must also be accepted and signed by the **authorised representative**.

The owner's signature may be handwritten or made through one of the signature
methods accepted in Spain. For foreign companies, the signature methods valid in
their country of origin are also accepted.

## Who can be the authorised representative?

It can be a person or entity that holds an **electronic certificate valid and
enabled to act in Spain**.

The authorised representative can carry out actions before the Sender Alias
Registry such as:

- requesting the registration of aliases;
- modifying, suspending or cancelling aliases already registered;
- providing documentation and responding to CNMC requirements;
- approving the requests submitted by origin providers;
- carrying out other necessary tasks related to the owner's aliases.

The authorisation is granted indefinitely, unless the owner expressly revokes it.

> **Note**: **Example: foreign company.** If the owner is a foreign company, such as a US
> LLC:
> 
> - the alias owner is the company;
> - a natural person with the authority to represent the company signs the letter
>   on its behalf;
> - the letter authorises another person or entity that holds a certificate valid
>   in Spain.
> 
> The company doesn't authorise its own legal representative: the legal
> representative signs on behalf of the company and authorises a third party so
> they can act electronically before the CNMC.

## How to use the letter in the Sender Alias Registry

Once the letter is filled in and signed:

#### 1. Access the process

Go to the **Gestión del Registro de Alias** (Sender Alias Registry management)
process at the CNMC's electronic office:
`https://sede.cnmc.gob.es/tramites/telecomunicaciones/gestion-del-registro-de-alias`.

#### 2. Applicant: «En representación de» (on behalf of)

Select **«En representación de»** (on behalf of) and enter the details of the
alias owner.

![Applicant section with «En representación de» selected and the alias owner's details](/platform/en/channels/images/spain-authorization-letters--1-solicitante-representacion.png)
*You choose «En representación de» (on behalf of) and enter the alias owner's details.*

#### 3. Request type: «Inscripción de Alias» (alias registration)

Select **«Inscripción de Alias»** (alias registration).

![Request type section with «Inscripción de Alias» selected](/platform/en/channels/images/spain-authorization-letters--2-inscripcion-de-alias.png)
*Request type «Inscripción de Alias» (alias registration).*

#### 4. Add the authorised representative

In the **«Representantes del titular»** (Brand owner's representatives) section,
add the details of the person or entity designated in the letter. Tick the
**«Autorizado»** (authorised) option and **attach the signed authorisation
letter**. Confirm with **«Añadir Representante»** (add representative).

![Brand owner's representative modal with the «Autorizado» checkbox ticked and the Attach authorisation letter button](/platform/en/channels/images/spain-authorization-letters--3-representante-autorizado-carta.png)
*With «Autorizado» (authorised) ticked, the signed authorisation letter is mandatory.*

## If Instasent submits the request

Instasent can submit the alias registration request as the origin provider.

The authorisation letter **does not automatically make Instasent the owner's
authorised representative**: the authorised representative will be exclusively the
person or entity expressly designated in the letter.

If Instasent submits the request and the owner can't approve it directly through a
certificate valid in Spain, the authorised representative can carry out the
necessary actions before the CNMC on the owner's behalf.

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