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# Resolve an identifier to its owner(s)

GET https://api.aventure.vc/v1/unique-ids/lookup

Resolves an external identifier to its owner(s). idType accepts a canonical token or alias; the value is normalized per type before matching. Returns every owner that carries the identifier (a value can recur across owners, e.g. a reused ticker), each row carrying its entityId or personId.

Reference: https://docs.aventure.vc/api-reference/a-venture-api/unique-i-ds/lookup-unique-id

## Authentication

- `Authorization` header (bearer token, required) — User bearer token: Supabase or Clerk session JWT, Clerk OAuth access token, or Clerk personal API key
- `X-API-Key` header (required) — Admin API key for system-to-system write operations
- `X-Client-Secret` header (required) — Client secret for read-only service-to-service access (no writes)

## Request

### Query parameters

- `idType` (string, required) — Identifier type token or alias, for example ein.
- `identifier` (string, required) — Identifier value to resolve.

## Response

### 200

OK

- `list of object`
  - `createdAt` (datetime, required) — Row creation timestamp.
  - `id` (integer, required) — Unique-id row id.
  - `idType` (enum, required) — Identifier type.
    - Allowed values: `ein`, `secCik`, `ticker`, `lei`, `duns`, `isin`, `cusip`, `crd`, `orcid`
  - `identifier` (string, required) — Identifier value as issued by the registry (normalized per type).
  - `owner` (object, required) — Owning entity or person id; exactly one nested id is present.
    - `entityId` (string, optional, nullable) — Canonical entity UUID
    - `personId` (string, optional, nullable) — Canonical person UUID
  - `updatedAt` (datetime, required) — Row update timestamp.
  - `source` (string, optional, nullable) — Attribution source label for the mapping, when recorded.

## Examples

**Response**

```json
[
  {
    "createdAt": "2024-01-15T09:30:00Z",
    "id": 1,
    "idType": "ein",
    "identifier": "string",
    "owner": {
      "entityId": "string",
      "personId": "string"
    },
    "updatedAt": "2024-01-15T09:30:00Z",
    "source": "string"
  }
]
```

**SDK Code**

```python
import requests

url = "https://api.aventure.vc/v1/unique-ids/lookup"

querystring = {"idType":"ein","identifier":"12-3456789"}

headers = {"Authorization": "Bearer <token>"}

response = requests.get(url, headers=headers, params=querystring)

print(response.json())
```

```javascript
const url = 'https://api.aventure.vc/v1/unique-ids/lookup?idType=ein&identifier=12-3456789';
const options = {method: 'GET', headers: {Authorization: 'Bearer <token>'}};

try {
  const response = await fetch(url, options);
  const data = await response.json();
  console.log(data);
} catch (error) {
  console.error(error);
}
```

```go
package main

import (
	"fmt"
	"net/http"
	"io"
)

func main() {

	url := "https://api.aventure.vc/v1/unique-ids/lookup?idType=ein&identifier=12-3456789"

	req, _ := http.NewRequest("GET", url, nil)

	req.Header.Add("Authorization", "Bearer <token>")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(res)
	fmt.Println(string(body))

}
```

```ruby
require 'uri'
require 'net/http'

url = URI("https://api.aventure.vc/v1/unique-ids/lookup?idType=ein&identifier=12-3456789")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Get.new(url)
request["Authorization"] = 'Bearer <token>'

response = http.request(request)
puts response.read_body
```

```java
import com.mashape.unirest.http.HttpResponse;
import com.mashape.unirest.http.Unirest;

HttpResponse<String> response = Unirest.get("https://api.aventure.vc/v1/unique-ids/lookup?idType=ein&identifier=12-3456789")
  .header("Authorization", "Bearer <token>")
  .asString();
```

```php
<?php
require_once('vendor/autoload.php');

$client = new \GuzzleHttp\Client();

$response = $client->request('GET', 'https://api.aventure.vc/v1/unique-ids/lookup?idType=ein&identifier=12-3456789', [
  'headers' => [
    'Authorization' => 'Bearer <token>',
  ],
]);

echo $response->getBody();
```

```csharp
using RestSharp;

var client = new RestClient("https://api.aventure.vc/v1/unique-ids/lookup?idType=ein&identifier=12-3456789");
var request = new RestRequest(Method.GET);
request.AddHeader("Authorization", "Bearer <token>");
IRestResponse response = client.Execute(request);
```

```swift
import Foundation

let headers = ["Authorization": "Bearer <token>"]

let request = NSMutableURLRequest(url: NSURL(string: "https://api.aventure.vc/v1/unique-ids/lookup?idType=ein&identifier=12-3456789")! as URL,
                                        cachePolicy: .useProtocolCachePolicy,
                                    timeoutInterval: 10.0)
request.httpMethod = "GET"
request.allHTTPHeaderFields = headers

let session = URLSession.shared
let dataTask = session.dataTask(with: request as URLRequest, completionHandler: { (data, response, error) -> Void in
  if (error != nil) {
    print(error as Any)
  } else {
    let httpResponse = response as? HTTPURLResponse
    print(httpResponse)
  }
})

dataTask.resume()
```