> ## Documentation Index
> Fetch the complete documentation index at: https://docs.clustr-ai.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Mark not a client

> Stop a company counting as a client, whatever its sources

Marks the company behind one source row "Not a client". Use it when a company is
on your list by mistake, most often because a CRM property says it is a client
when it is not.

**It overrides every source.** Clustr copies the row's matched company, LinkedIn
numeric id, LinkedIn slug and domain. Any row sharing one of them stops counting
as a client: manual, csv and CRM rows alike, including rows your CRM brings in on
later syncs. The company stays on the list with `excluded: true`, and is left out
of the [summary](/api-reference/get-client-companies-summary) counts and of
[exclude client companies](/client-companies#exclude-client-companies).

**Marking twice is safe.** If the company is already marked, the existing
exclusion's id is returned and nothing new is created.

To undo it, pass the id to [Undo not a client](/api-reference/undo-not-a-client).

## Body

<ParamField body="sourceRowId" type="string" required>
  Any source row id from the company's `sources` in
  [List client companies](/api-reference/list-client-companies), from any source.
</ParamField>

## Errors

| Status | Code           | When                                                                                                                                                                         |
| ------ | -------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| 400    | `BAD_REQUEST`  | The body is not valid JSON, or `sourceRowId` is not a uuid                                                                                                                   |
| 404    | `NOT_FOUND`    | No such row in this workspace                                                                                                                                                |
| 422    | `no_match_key` | The row has no LinkedIn page, no domain and no matched company, so there is nothing to match on. This happens with a CRM record that has neither a LinkedIn URL nor a domain |

<RequestExample>
  ```bash cURL theme={null}
  curl -X POST https://api.clustr-ai.com/api/public/client-companies/exclusions \
    -H "Authorization: Bearer YOUR_API_KEY" \
    -H "Content-Type: application/json" \
    -d '{"sourceRowId": "a3c9f1b4-..."}'
  ```
</RequestExample>

<ResponseExample>
  ```json 201 theme={null}
  {
    "success": true,
    "data": { "id": "c41d8e07-..." }
  }
  ```

  ```json 404 theme={null}
  {
    "success": false,
    "error": { "message": "Client company not found", "code": "NOT_FOUND" }
  }
  ```

  ```json 422 theme={null}
  {
    "success": false,
    "error": { "message": "This company has no LinkedIn page or domain to match on yet", "code": "no_match_key" }
  }
  ```
</ResponseExample>