---
title: "Start a signature process"
method: POST
path: "/v1/signatures/{signatureId}"
tags: ["Qualified Electronic Signature"]
---

# Start a signature process

`POST /v1/signatures/{signatureId}`

Use this endpoint to trigger processing of a Qualified Electronic Signature case <br /><br /><img src="https://files.readme.io/310d4d3-Inline_Caution.svg" align="left" alt="Important" /> **Important:** <code>signatureId</code> and <code>workflowId</code> are string identifiers that can be used interchangeably.

## Path parameters

- `signatureId` string, required

## Query parameters

- `lang` 'de' | 'en' | 'es' | 'fr' | 'it' | 'pl' | 'pt' | 'ro'

## Headers

- `Authorization` string, required — The `access_token` returned in your most recent [Create access token](https://docs.fourthline.com/reference/create-access-token) response.

## Request body

- object
  - `deviceMetaData` object — The metadata from the client’s device.
    - `language` string — The language of the client’s device. <br /><br />Format: ISO 3166-1 alpha-2 <br /><br />Example: `NL`
    - `region` string — The country code of the client’s device geolocation. <br /><br />Format: ISO 3166-1 alpha-2, e.g. `IT` **or** ISO 3166-1 alpha-3, e.g. `ITA`
    - `model` string — The model of the client’s device. <br /><br /><img src="https://files.readme.io/8eb9022-Inline_Tip.svg" align="left"/> **Tip:** **Required** for workflows that include Qualified Electronic Signature, so that we can check it matches the client’s Identity Verification case. <br /><br />Example: OnePlus Nord CE 5G
    - `ipAddress` string — The IP address of the client’s device. <br /><br />Example: 185.128.27.102
    - `latitude` string — The latitude of the client’s device geolocation <br /><br />Format: Float between -90 and 90 <br /><br />Example: 45.464664
    - `longitude` string — The longitude of the client’s device geolocation. <br /><br />Format: Float between -180 and 180 <br /><br />Example: 9.188540
    - `browserVersion` string — The version of the browser the client’s device is using. <br /><br />Example: 116.0.5845.172
    - `osCompromised` string — Whether the operating system of the client’s device is compromised.
    - `osVersion` string — The version of the operating system of the client’s device. <br /><br />Example: Android 13
    - `sdkVersion` string — The version of the SDK used. <br />Set to `v1`.
    - `analyticsId` string — The identifier for the metadata analytics.
  - `mobilePhoneNumber` string — The client’s mobile phone number, which you have ensured is valid. <br /><br />Format: +{prefixNumber} {phoneNumber} <br /><img src="https://files.readme.io/ad2486a-Inline_Note.svg" align="left"/> **Notes**: <br />• Always include a **space** between the prefix and phone number. <br />• The prefix can contain a maximum of **4** digits. <br /><br />Example: `+31 612345678`

## Response `200`

Signature process started

- object — A successful response is empty.

## Other responses

- `400` — Invalid request parameters
- `404` — Signature not found

---

[API](https://skmtc.net/fourthline/apis/fourthline-apis.md) · [All operations](https://skmtc.net/fourthline/apis/fourthline-apis/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/fourthline/fourthline-apis/revisions/7991ae7c8383/schema)