---
title: "Leads"
description: "Leads: available fields, filters, associations, and API operations."
lastModified: "2026-08-21"
---

**Path:** `events/{event_id}/leads`  
**Methods:** GET collection/record, POST, PATCH, DELETE.

**GET**

- Fields: `event-id`, `sponsor-ids`, `registrant-id`, `created-by-registrant-id`, `notes`, `created-at`, `updated-at`.  
- Filters: `sponsor_id`, `registrant_id`, `created_by_registrant_id`, `created_from`, `created_to`, `updated_from`, `updated_to`.  
- Associations:  
  - `sponsors`: linkage only;  
  - `registrant`: `external-id`, `first-name`, `last-name`, `email`;  
  - `created_by_registrant` → response `created-by-registrant`: `external-id`, `first-name`, `last-name`, `email`;  
  - `custom_fields` → response `custom-fields`: `definition-key`, `definition-title`, `field-type`, `values`.  
- Row restriction: by the `sponsors` association.

```
GET .../leads?sponsor_id=103705&include=registrant,created_by_registrant,custom_fields
```

**POST/PATCH inputs:** `registrant_id`, `created_by_registrant_id`, `notes`, `sponsor_id`, `custom_fields_attributes` (raw JSON). The custom-field input is consumed on PATCH; lead creation does not process lead-scan answers.

```json
{
  "sponsor_id": 103705,
  "registrant_id": 1201,
  "created_by_registrant_id": 1301,
  "notes": "Requested pricing information"
}
```

The target registrant, optional creator registrant, sponsor, and custom fields must belong to the URL event. On a scope restricted to exactly one sponsor, POST may omit `sponsor_id`; the restricted sponsor is injected. A sponsor-restricted scope cannot change `created_by_registrant_id` on PATCH. A lead created without a creator correctly returns `created-by-registrant-id: null` and a null relationship.

Lead-scan answers on PATCH use the configured request key for `custom_fields_attributes` and this raw shape:

```json
{
  "custom_fields_attributes": [
    {
      "sponsor_id": 103705,
      "question_id": 901,
      "values": ["Q4"]
    }
  ]
}
```