# List Custom Object instances

GET https://api.close.com/api/v1/custom_object/

The `lead_id` parameter is required. If you want to retrieve all Custom Object instances regardless of the lead, you will need to use [Advanced Filtering](https://developer.close.com/resources/advanced-filtering/).

Custom Fields values appear in the format: `custom.{custom_field_id}`. See [Custom Fields](/resources/custom-fields/custom-object-custom-fields/).

Back references to each Custom Object are not collected in this response. If you need to access this information, please use the `back_reference_fields` on the Custom Object Type and [Advanced Filtering](/resources/advanced-filtering/) to search for objects that reference the Custom Object Instance.

Reference: https://developer.close.com/api/resources/custom-objects/list

## OpenAPI Specification

```yaml
openapi: 3.1.0
info:
  title: Close API
  version: 1.0.0
paths:
  /custom_object/:
    get:
      operationId: list
      summary: List Custom Object instances
      description: >-
        The `lead_id` parameter is required. If you want to retrieve all Custom
        Object instances regardless of the lead, you will need to use [Advanced
        Filtering](https://developer.close.com/resources/advanced-filtering/).


        Custom Fields values appear in the format: `custom.{custom_field_id}`.
        See [Custom
        Fields](/resources/custom-fields/custom-object-custom-fields/).


        Back references to each Custom Object are not collected in this
        response. If you need to access this information, please use the
        `back_reference_fields` on the Custom Object Type and [Advanced
        Filtering](/resources/advanced-filtering/) to search for objects that
        reference the Custom Object Instance.
      tags:
        - subpackage_customObjects
      parameters:
        - name: lead_id
          in: query
          required: true
          schema:
            type: string
        - name: custom_object_type_id
          in: query
          required: false
          schema:
            type:
              - string
              - 'null'
        - name: Authorization
          in: header
          description: Basic authentication
          required: true
          schema:
            type: string
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/custom_objects_list_Response_200'
        '400':
          description: Bad request
          content:
            application/json:
              schema:
                description: Any type
        '401':
          description: Unauthorized
          content:
            application/json:
              schema:
                description: Any type
        '404':
          description: Not found
          content:
            application/json:
              schema:
                description: Any type
servers:
  - url: https://api.close.com/api/v1
components:
  schemas:
    custom_objects_list_Response_200:
      type: object
      properties: {}
      description: Empty response body
      title: custom_objects_list_Response_200
  securitySchemes:
    ApiKeyAuth:
      type: http
      scheme: basic
    OAuth2:
      type: http
      scheme: bearer

```