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

# Identifiers

> How the LENS API identifies companies, persons, addresses, properties, vehicles, watchlists, and orders — internal IDs, registration numbers, external UUIDs, and GUIDs.

The API uses several types of identifiers to reference entities. Understanding how they relate is key to navigating between endpoints.

## Internal IDs

Every entity has a numeric internal ID that is stable and unique within its type.

| Entity    | ID field             | Type | Example   |
| --------- | -------------------- | ---- | --------- |
| Company   | `companyId`          | int  | `3508351` |
| Person    | `personId`           | int  | `2954253` |
| Address   | `addressId`          | int  | `12345`   |
| Vehicle   | `vehicleId`          | int  | `789012`  |
| Property  | `propertyId`         | int  | `456789`  |
| Workplace | `companyWorkplaceId` | int  | `234567`  |

These IDs are used across all API endpoints:

```
GET /companies/3508351
GET /companies/3508351/representatives
GET /companies/3508351/documents
GET /persons/2954253
GET /vehicles/789012
```

## Registration numbers

Companies can also be looked up by their local registration number (e.g. Swedish organisationsnummer). The registration number is available as a field in search results and company details.

| Field                    | Description                        | Example           |
| ------------------------ | ---------------------------------- | ----------------- |
| `registrationNumber`     | Local registration number          | `5565199493`      |
| `personalIdentityNumber` | Personal identity number (persons) | Varies by country |

To find a company by registration number, use the search API:

```bash theme={null}
curl -H "x-api-key: YOUR_API_KEY" \
  "https://lens-api.tic.io/search-public/companies?q=5565199493&query_by=registrationNumber"
```

The `companyId` from the search result can then be used with all `/companies/{id}/...` endpoints.

## External UUIDs (Sweden)

Swedish properties and addresses from Lantmäteriet have external UUIDs. These can be used as an alternative lookup:

```
GET /properties/se/{uuid}
GET /properties/se/{uuid}/summary
GET /addresses/se/{uuid}
```

## Watchlist IDs

Watchlists and their sub-resources use GUIDs:

| Entity           | Type | Example             |
| ---------------- | ---- | ------------------- |
| Watchlist        | Guid | `a1b2c3d4-e5f6-...` |
| Watchlist member | Guid | `f6e5d4c3-b2a1-...` |
| Notification     | Guid | `12345678-abcd-...` |
| Subscription     | Guid | `abcdef01-2345-...` |

See [Watchlists](/api-lens/watchlists) for how these are used.

## Order IDs

Document orders are identified by GUIDs:

```
GET /orders/{orderGuid}
GET /orders/{orderGuid}/content
GET /orders/{orderGuid}/file
```

## Connecting the dots

<Steps>
  <Step title="Search">
    Search for a company by name or registration number to get `companyId`.
  </Step>

  <Step title="Fetch details">
    Use `GET /companies/{companyId}` to get the full company record.
  </Step>

  <Step title="Drill into sub-resources">
    Use `GET /companies/{companyId}/representatives` to get `personId` values.
  </Step>

  <Step title="Follow connections">
    Use `GET /persons/{personId}` or `POST /persons/{personId}/companies` to see their other positions.
  </Step>

  <Step title="Monitor changes">
    Use `POST /watchlists/{watchlistGuid}/companies/{companyId}` to add the company to a watchlist.
  </Step>
</Steps>