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

# List Importable Order Books

> Discover external securities books other instances have published

Returns the external securities books that other instances have opened for import and that you have not imported yet. A book qualifies when it is `ACTIVE`, settles on-chain, has `allowImport` set, and belongs to another instance. Newest first, capped at 100 entries.

Importing is how you quote a security another venue already lists. Combined with shared liquidity on both sides, it is how two venues end up matching against one pool of depth on the same instrument.

## Response Fields

<ResponseField name="data" type="array">
  <Expandable>
    <ResponseField name="id" type="string">Order book ID. Pass it to [Import Order Book](/endpoints/external-securities-trading/import-order-book).</ResponseField>
    <ResponseField name="tokenAddress" type="string">Security token.</ResponseField>
    <ResponseField name="quoteTokenAddress" type="string">Settlement asset.</ResponseField>
    <ResponseField name="name" type="string">Display name.</ResponseField>
    <ResponseField name="symbol" type="string">Display symbol.</ResponseField>
    <ResponseField name="tokenType" type="string">`EXTERNAL_SECURITY`.</ResponseField>
    <ResponseField name="custodyContract" type="string">Custody contract the book settles through.</ResponseField>
    <ResponseField name="minOrderSize" type="string">Minimum quantity in order book units.</ResponseField>
    <ResponseField name="maxOrderSize" type="string">Maximum quantity, or `null`.</ResponseField>
    <ResponseField name="tickSize" type="string">Price increment in order book units.</ResponseField>
    <ResponseField name="makerFeeBps" type="integer">Maker fee charged by the owning book.</ResponseField>
    <ResponseField name="takerFeeBps" type="integer">Taker fee charged by the owning book.</ResponseField>
    <ResponseField name="createdAt" type="string">ISO 8601 timestamp.</ResponseField>
  </Expandable>
</ResponseField>

<Note>
  The summary does not include the instrument identifier or the recorded decimals. Import the book to read its full record, then use [Get Security Status](/endpoints/external-securities-trading/get-security-status) for the on-chain detail.
</Note>

<RequestExample>
  ```bash cURL theme={null}
  curl "https://api.trusset.org/orderbooks/external-securities/api/order-books/importable" \
    -H "X-API-Key: trusset_your_key_here"
  ```

  ```typescript TypeScript theme={null}
  const res = await fetch(
    'https://api.trusset.org/orderbooks/external-securities/api/order-books/importable',
    { headers: { 'X-API-Key': 'trusset_your_key_here' } }
  );
  const { data } = await res.json();
  ```
</RequestExample>

<ResponseExample>
  ```json Response theme={null}
  {
    "success": true,
    "data": [
      {
        "id": "clx_ob_extsec_088",
        "tokenAddress": "0x51f2b9d0e77c4a1b83ce6d4a9271e5f3a0c8b912",
        "quoteTokenAddress": "0x98ad0ca091552e23c564b41c74282e5343d03e8a",
        "name": "Helvetia Growth Fund",
        "symbol": "HELG",
        "tokenType": "EXTERNAL_SECURITY",
        "custodyContract": "0x489aee4ae9546081d55848f157e03192e826988c",
        "minOrderSize": "1000000",
        "maxOrderSize": null,
        "tickSize": "10000",
        "makerFeeBps": 0,
        "takerFeeBps": 10,
        "createdAt": "2025-05-20T14:12:00.000Z"
      }
    ]
  }
  ```
</ResponseExample>

## Error Codes

| Code                  | HTTP  | Cause                                               |
| --------------------- | ----- | --------------------------------------------------- |
| `SERVICE_NOT_ENABLED` | `403` | The Trading service is not enabled on this instance |